Merge commit 'f1a9ab14fe882f9b855ea9cc3f16ddc9a3b0284d' into codex/bounded-background-tasks-v2

# Conflicts:
#	.agents/notes/implemented/architecture/2026-06-20-generic-long-running-tool-runtime.i18n.yaml
#	.agents/notes/implemented/architecture/2026-06-20-generic-long-running-tool-runtime.md
#	.agents/notes/implemented/architecture/2026-06-20-generic-long-running-tool-runtime.zh.md
#	.agents/notes/implemented/architecture/2026-07-26-task-registry-seam.i18n.yaml
#	.agents/notes/implemented/architecture/2026-07-26-task-registry-seam.md
#	.agents/notes/implemented/architecture/2026-07-26-task-registry-seam.zh.md
#	docs/config-catalog.i18n.yaml
#	docs/config-catalog.md
#	docs/config-catalog.zh.md
#	docs/subsystems/tasks.i18n.yaml
#	docs/subsystems/tasks.md
#	docs/subsystems/tasks.zh.md
#	packages/examples/acp-demo/src/index.ts
#	packages/tasks/tasks-local/tests/tasks.spec.ts
#	packages/tasks/tasks/README.i18n.yaml
#	packages/tasks/tasks/README.md
#	packages/tasks/tasks/README.zh.md

examples/acp-agent/cordis.yml

@@ -121,12 +121,16 @@
     backgroundMode: continuable
     maxDepth: 1
 
+# Fork stays one-shot because a continuable child's `report` tool and prompt
+# section precede the inherited history a fork reuses; `run_in_background` is off
+# because this example mounts no task service. See .agents/notes/implemented/architecture/2026-08-10-fork-children-stay-one-shot.md.
 - id: tool-subagent-fork
   name: '@deepseek-ai/dsh-tool-subagent'
   config:
     provider: fork
     toolName: subagent_fork
-    backgroundMode: continuable
+    backgroundMode: one-shot
+    enableRunInBackground: false
     maxDepth: 1
 
 

examples/acp-agent/subagent-report-quiet.cordis.snapshot.yml

@@ -0,0 +1,51 @@
+# Keyless counterpart to subagent-report-quiet.cordis.yml: replace the live
+# adapter with replay, keep report delivery quiet, and fence the child behind
+# the end of its parent's spawn turn so settlement opens the next turn.
+- id: base
+  name: '@deepseek-ai/cordis-plugin-include'
+  config:
+    path: ./cordis.yml
+    patches:
+      - id: llm-deepseek
+        name: '@deepseek-ai/dsh-llm-deepseek'
+        disabled: true
+      - id: acp-agent
+        name: '@deepseek-ai/dsh-acp-demo'
+        config:
+          provider: deepseek-official
+          model: deepseek-v4-flash
+          persistenceRoot: !!js process.env.DSH_SNAPSHOT_SESSIONS_ROOT ?? './.sessions'
+          persistenceCompression: none
+          workspaceContext:
+            maxBytes: 65536
+          persona: |
+            You are a coding assistant powered by the {{model}} model. Your working directory is {{cwd}}. Your bash tool runs under a file sandbox — a `[sandbox: file access denied …]` result is policy, not a command bug.
+
+            Verify your work by running the code or tests. Keep answers brief and factual.
+      - id: sandbox
+        name: '@deepseek-ai/dsh-sandbox-local'
+        config:
+          runnerCommand:
+            - bash
+            - -c
+            - while [ "$1" != "--" ]; do shift; done; shift; exec "$@"
+            - passthrough-runner
+          runnerFailureSignatures:
+            - 'passthrough-runner: profile rejected'
+      - id: tool-subagent-report
+        name: '@deepseek-ai/dsh-tool-subagent-report'
+        config:
+          reportDelivery: quiet
+      - insert:
+          - id: llm-replay
+            name: '@deepseek-ai/dsh-llm-replay'
+            config:
+              providers:
+                - id: deepseek-official
+                  name: DeepSeek
+                  models:
+                    - id: deepseek-v4-flash
+                    - id: deepseek-v4-pro
+
+- id: report-fence
+  name: './tests/fixtures/subagent-report-fence.ts'

examples/acp-agent/subagent-report-quiet.cordis.yml

@@ -0,0 +1,17 @@
+# Snapshot-only overlay pinning quiet report delivery. The shipped default wakes
+# the parent on every accepted report, and the runtime's settlement notice wakes
+# it again when the child's Activation ends; two independent wakes have no single
+# authored order. Quiet delivery leaves settlement as the only wake, while the
+# fixture below holds the child until the parent's spawn turn has closed.
+- id: base
+  name: '@deepseek-ai/cordis-plugin-include'
+  config:
+    path: ./cordis.yml
+    patches:
+      - id: tool-subagent-report
+        name: '@deepseek-ai/dsh-tool-subagent-report'
+        config:
+          reportDelivery: quiet
+
+- id: report-fence
+  name: './tests/fixtures/subagent-report-fence.ts'

examples/acp-agent/tests/acp.snapshot.ts

@@ -46,6 +46,9 @@ const CHILD_QUESTION_CONFIG = fileURLToPath(new URL('../child-question.cordis.ym
 const SESSION_SANDBOX_ROOT_CONFIG = fileURLToPath(new URL('../session-sandbox-root.cordis.yml', import.meta.url))
 const RETRY_CONFIG = fileURLToPath(new URL('../retry.cordis.yml', import.meta.url))
 const SESSION_TITLE_CONFIG = fileURLToPath(new URL('../session-title.cordis.yml', import.meta.url))
+const SUBAGENT_REPORT_QUIET_CONFIG = fileURLToPath(
+  new URL('../subagent-report-quiet.cordis.yml', import.meta.url),
+)
 const SUBAGENT_DURABILITY_FAILURE_CONFIG = fileURLToPath(
   new URL('../subagent-durability-failure.cordis.yml', import.meta.url),
 )
@@ -396,12 +399,19 @@ const SCENARIOS: Scenario[] = [
   // turns on that same child (the parent is never woken with their output),
   // send_message to an unknown subagent id fails without delivering, and the
   // child's retained handle is disposed child-first at teardown despite a
-  // failed final durability confirmation.
+  // failed final durability confirmation. That failed confirmation is also what
+  // the settlement notice must report: the child's last turn claimed the third
+  // message and then died on its durability checkpoint without entering a step,
+  // so the notice opening the parent's second turn says the child FAILED and the
+  // parent must not read the earlier answer as final. The scenario's fixture
+  // fences the child behind the parent's spawn turn so that notice can only
+  // arrive at an idle parent.
   {
     name: 'subagent-continuable',
     hasModelTurn: true,
     recorded: false,
     pinsChildToolSchemas: [1],
+    pinsChildSystemPrompts: [1],
     configPath: SUBAGENT_DURABILITY_FAILURE_CONFIG,
   },
   // Authored policy-inheritance transcript: the root session is switched to
@@ -409,11 +419,14 @@ const SCENARIOS: Scenario[] = [
   // continuable background child's log carries that override as a
   // `sandbox/mode` `source: 'delegation'` event, so the child's runtime
   // context states the inherited policy instead of the deployment default.
+  // The input also waits for the manager-owned settlement turn, keeping that
+  // delivery from racing transcript harvest.
   {
     name: 'subagent-continuable-inheritance',
     hasModelTurn: true,
     recorded: false,
     pinsChildToolSchemas: [1],
+    pinsChildSystemPrompts: [1],
     configPath: SUBAGENT_CONTINUABLE_INHERITANCE_CONFIG,
   },
   // The in-process child is published before its first follow-up fails. The
@@ -428,13 +441,18 @@ const SCENARIOS: Scenario[] = [
     configPath: SUBAGENT_DURABILITY_FAILURE_CONFIG,
   },
   // Authored child-to-parent transcript: the child calls its scope-local
-  // `report`, quiet delivery reaches the idle parent without waking it, and a
-  // later parent turn consumes the logged report.
+  // `report`, and the runtime's unconditional settlement notice then wakes the
+  // parked parent into one ordinary turn that claims both. The overlay pins
+  // quiet report delivery because two independent wakes have no orderable
+  // transcript; the shipped waking default is covered by package tests.
   {
     name: 'subagent-report',
     hasModelTurn: true,
     recorded: false,
+    overridden: false,
+    configPath: SUBAGENT_REPORT_QUIET_CONFIG,
     pinsChildToolSchemas: [1],
+    pinsChildSystemPrompts: [1],
   },
   // Authored durable-catalog transcript: the snapshot-only lifecycle marker
   // fences the second parent turn behind the child's Activation end, so
@@ -447,6 +465,7 @@ const SCENARIOS: Scenario[] = [
     hasModelTurn: true,
     recorded: false,
     pinsChildToolSchemas: [1],
+    pinsChildSystemPrompts: [1],
   },
   {
     name: 'subagent-depth-two-rejection',

examples/acp-agent/tests/fixtures/subagent-durability-failure.ts

@@ -31,6 +31,8 @@ const FAILED_CHECKPOINT_TURN = 3
 /** Fail the child checkpoint and stabilize the authored follow-up failure ordering. */
 export function apply(ctx: Context): void {
   const followupsAccepted = Promise.withResolvers<undefined>()
+  const parentTurnClosed = Promise.withResolvers<undefined>()
+  let parentClosed = false
   const publishedFailure = process.env.DSH_SUBAGENT_PUBLISHED_FAILURE === '1'
   const persistence = ctx.sessionPersistence
   const load = persistence.load.bind(persistence)
@@ -62,8 +64,22 @@ export function apply(ctx: Context): void {
     agents.create = create
     persistence.load = load
     followupsAccepted.resolve(undefined)
+    parentTurnClosed.resolve(undefined)
   }, 'subagent snapshot ordering')
 
+  // The manager's settlement notice races whatever the parent is doing when the
+  // child's Activation ends, and this transcript pins it as the parent's own
+  // later turn. Hold the child's steps until the parent's spawn turn closes, so
+  // the notice can only arrive at an idle parent. The parent's turn never awaits
+  // child model work — its own fences need inbox acceptance only — so the child
+  // cannot deadlock it.
+  ctx.on('session/event', (session, event) => {
+    if (session.header.parentSession !== undefined || event.type !== 'turn/end') return
+    if (event.data.turn !== 1) return
+    parentClosed = true
+    parentTurnClosed.resolve(undefined)
+  })
+
   // Remap the placeholder child id in a follow-up to the live child. The child
   // id the model "knows" is authored into the transcript, while the running
   // child is minted with a random id, so without this the follow-ups would
@@ -91,7 +107,12 @@ export function apply(ctx: Context): void {
     if (accepted >= 3) followupsAccepted.resolve(undefined)
   })
   ctx.on('agent/pre-step', async ({ agent }, next) => {
-    if (agent.session.header.parentSession !== undefined) await followupsAccepted.promise
+    if (agent.session.header.parentSession === undefined) return next()
+    await followupsAccepted.promise
+    // The published-failure variant's child never reaches a step (its follow-up
+    // throws), and its parent turn awaits that child, so only the continuable
+    // scenario takes the settlement fence.
+    if (!publishedFailure && !parentClosed) await parentTurnClosed.promise
     return next()
   })
 

examples/acp-agent/tests/fixtures/subagent-report-fence.ts

@@ -0,0 +1,41 @@
+/**
+ * Loader fixture that holds the report child until its parent's spawn turn ends.
+ * @module subagent-report-fence
+ */
+
+import type { Context } from '@deepseek-ai/cordis'
+import type {} from '@deepseek-ai/dsh-agent-loop'
+
+/** Fixture plugin name. */
+export const name = 'subagent-report-fence'
+
+/**
+ * Keep replay scheduling from folding settlement into the parent's first turn.
+ * @param ctx - assembled ACP-agent context.
+ */
+export function apply(ctx: Context): void {
+  const childReady = Promise.withResolvers<undefined>()
+  const parentStopped = Promise.withResolvers<undefined>()
+  let hasStopped = false
+
+  ctx.effect(() => {
+    const disposeSession = ctx.root.on('session/event', (session, event) => {
+      if (session.header.parentSession !== undefined || event.type !== 'turn/end' || event.data.turn !== 1) return
+      hasStopped = true
+      parentStopped.resolve(undefined)
+    })
+    const disposeStep = ctx.root.on('agent/pre-step', async ({ agent, turn, step }, next) => {
+      if (agent.session.header.parentSession !== undefined) {
+        childReady.resolve(undefined)
+        if (!hasStopped) await parentStopped.promise
+      } else if (turn === 1 && step === 2) {
+        await childReady.promise
+      }
+      return next()
+    })
+    return () => {
+      disposeStep()
+      disposeSession()
+    }
+  }, 'subagent-report-fence.listeners')
+}

examples/acp-agent/tests/snapshots/advanced-toolchain/session.1.jsonl

@@ -6,7 +6,7 @@
 {"type":"subagent/descriptor","seq":4,"time":1786357538308,"data":{"version":2,"mode":"one-shot","provider":"spawn","label":"Check direct child"}}
 {"type":"step/start","seq":5,"time":1786357538310,"data":{"turn":1,"step":1}}
 {"type":"user/message","seq":6,"time":1785730458555,"data":{"content":[{"type":"text","text":"Reply with exactly DIRECT_CHILD_OK and nothing else."}],"source":{"kind":"user"},"role":"user","id":"ebe0cfa0-a909-47e0-8294-28ad84a8fe77"},"surfaceOp":"append"}
-{"type":"user/message","seq":7,"time":1786357538310,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"b8a6a626-fd2c-4602-a8d4-8074f229bfb5"},"surfaceOp":"append"}
+{"type":"user/message","seq":7,"time":1786357538310,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"3f5d0f63-fcf4-4b04-9c1f-6aabf60c8877"},"surfaceOp":"append"}
 {"type":"session/title","seq":8,"time":1786357538310,"data":{"title":"Reply with exactly DIRECT_CHILD_OK and","messageSeqs":[6],"source":{"kind":"fallback"}}}
 {"type":"request/header","seq":9,"time":1785730458555,"data":{"header":{"config":{"provider":"deepseek-official","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"initial"}}
 {"type":"request/context","seq":10,"time":1785730458555,"data":{"provider":"deepseek-official","model":"deepseek-v4-flash"}}

examples/acp-agent/tests/snapshots/advanced-toolchain/session.2.jsonl

@@ -6,7 +6,7 @@
 {"type":"subagent/descriptor","seq":4,"time":1786357538469,"data":{"version":2,"mode":"one-shot","provider":"spawn"}}
 {"type":"step/start","seq":5,"time":1786357538470,"data":{"turn":1,"step":1}}
 {"type":"user/message","seq":6,"time":1785730458703,"data":{"content":[{"type":"text","text":"Reply with exactly WORKFLOW_CHILD_OK and nothing else."}],"source":{"kind":"user"},"role":"user","id":"2ac2cc54-9bce-4cfa-a569-a64f51bc30a7"},"surfaceOp":"append"}
-{"type":"user/message","seq":7,"time":1786357538471,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"d327cdff-ad2e-4f9e-9c54-d4448ee11f2a"},"surfaceOp":"append"}
+{"type":"user/message","seq":7,"time":1786357538471,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"2bb5fd9d-ecb5-4597-ba8d-6626409278f5"},"surfaceOp":"append"}
 {"type":"session/title","seq":8,"time":1786357538471,"data":{"title":"Reply with exactly WORKFLOW_CHILD_OK and","messageSeqs":[6],"source":{"kind":"fallback"}}}
 {"type":"request/header","seq":9,"time":1785730458703,"data":{"header":{"config":{"provider":"deepseek-official","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"initial"}}
 {"type":"request/context","seq":10,"time":1785730458703,"data":{"provider":"deepseek-official","model":"deepseek-v4-flash"}}

examples/acp-agent/tests/snapshots/advanced-toolchain/session.jsonl

@@ -4,7 +4,7 @@
 {"type":"agent/inbox/spliced","seq":2,"time":1785821417919,"data":{"target":"next-turn","start":0,"removedCount":1,"inserted":[]}}
 {"type":"step/start","seq":3,"time":1783957884486,"data":{"turn":1,"step":1}}
 {"type":"user/message","seq":4,"time":1785498801761,"data":{"content":[{"type":"text","text":"Run this advanced flow exactly once: try a no-op temporary Cordis Plugin named snapshot-marker; use run_code to inspect the live temporary Plugins through tools.cordis_inspect; delegate once to a direct spawn child; run one workflow that delegates to another spawn child; stop dyn-1; then reply with exactly ADVANCED_ACP_OK."}],"source":{"kind":"user"},"role":"user","id":"6e45782a-31be-4ba7-8c4a-7411a2027e36"},"surfaceOp":"append"}
-{"type":"user/message","seq":5,"time":1785730458430,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."}]},"role":"user","id":"06416873-c855-452d-8996-ea5cf45223d1"},"surfaceOp":"append"}
+{"type":"user/message","seq":5,"time":1785730458430,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."}]},"role":"user","id":"b6de532e-08ff-42b0-abae-1895dc463500"},"surfaceOp":"append"}
 {"type":"session/title","seq":6,"time":1785730458430,"data":{"title":"Run this advanced flow exactly","messageSeqs":[4],"source":{"kind":"fallback"}}}
 {"type":"request/header","seq":7,"time":1785498801765,"data":{"header":{"config":{"provider":"deepseek-official","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"initial"}}
 {"type":"request/context","seq":8,"time":1785730458431,"data":{"provider":"deepseek-official","model":"deepseek-v4-flash"}}

examples/acp-agent/tests/snapshots/advanced-toolchain/system-prompt.expected.md

@@ -99,7 +99,7 @@ interface ToolArgsMap {
     /** The agent id of the running agent to interrupt. */
     agent_id: string;
   } & Record<string, JsonValue>;
-  /** List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only. */
+  /** List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only. */
   list_agents: {
     /** children (default) lists direct children only; descendants walks the complete tree below you. */
     scope?: "children" | "descendants";
@@ -132,23 +132,21 @@ interface ToolArgsMap {
     /** The exact skill name from the available skills list. */
     name: string;
   } & Record<string, JsonValue>;
-  /** Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work. */
+  /** Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work. */
   subagent: {
     /** A short (3-5 word) description of the delegated task, for display. */
     description: string;
     /** The complete, self-contained task for the subagent. It does not share this conversation's context, so include everything it needs. */
     prompt: string;
-    /** Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message. */
+    /** Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message. */
     run_in_background?: boolean;
   } & Record<string, JsonValue>;
-  /** Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work. */
+  /** Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. */
   subagent_fork: {
     /** A short (3-5 word) description of the delegated task, for display. */
     description: string;
     /** The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new. */
     prompt: string;
-    /** Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message. */
-    run_in_background?: boolean;
   } & Record<string, JsonValue>;
   /** Request cancellation of a running background task by task id. Returns immediately; the task settles as killed once its work actually stops. */
   task_kill: {
@@ -319,7 +317,7 @@ interface ToolOutputMap {
     kind: "child";
     id: string;
     label: string;
-    status: "running" | "idle" | "complete";
+    status: "running" | "idle" | "ready";
     parent?: string;
     depth?: number;
   } | {

examples/acp-agent/tests/snapshots/advanced-toolchain/tool-schemas.expected.json

@@ -190,7 +190,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -309,7 +309,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -323,7 +323,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -334,7 +334,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -345,10 +345,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/both-mode-turn/tool-schemas.expected.json

@@ -133,7 +133,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -252,7 +252,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -266,7 +266,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -277,7 +277,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -288,10 +288,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/code-mode-turn/system-prompt.expected.md

@@ -82,7 +82,7 @@ interface ToolArgsMap {
     /** The agent id of the running agent to interrupt. */
     agent_id: string;
   } & Record<string, JsonValue>;
-  /** List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only. */
+  /** List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only. */
   list_agents: {
     /** children (default) lists direct children only; descendants walks the complete tree below you. */
     scope?: "children" | "descendants";
@@ -115,23 +115,21 @@ interface ToolArgsMap {
     /** The exact skill name from the available skills list. */
     name: string;
   } & Record<string, JsonValue>;
-  /** Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work. */
+  /** Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work. */
   subagent: {
     /** A short (3-5 word) description of the delegated task, for display. */
     description: string;
     /** The complete, self-contained task for the subagent. It does not share this conversation's context, so include everything it needs. */
     prompt: string;
-    /** Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message. */
+    /** Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message. */
     run_in_background?: boolean;
   } & Record<string, JsonValue>;
-  /** Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work. */
+  /** Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. */
   subagent_fork: {
     /** A short (3-5 word) description of the delegated task, for display. */
     description: string;
     /** The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new. */
     prompt: string;
-    /** Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message. */
-    run_in_background?: boolean;
   } & Record<string, JsonValue>;
   /** Request cancellation of a running background task by task id. Returns immediately; the task settles as killed once its work actually stops. */
   task_kill: {
@@ -290,7 +288,7 @@ interface ToolOutputMap {
     kind: "child";
     id: string;
     label: string;
-    status: "running" | "idle" | "complete";
+    status: "running" | "idle" | "ready";
     parent?: string;
     depth?: number;
   } | {

examples/acp-agent/tests/snapshots/lsp-definition/tool-schemas.expected.json

@@ -133,7 +133,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -268,7 +268,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -282,7 +282,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -293,7 +293,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -304,10 +304,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/product-subagent-both/tool-schemas.expected.json

@@ -133,7 +133,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -231,7 +231,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -245,7 +245,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -298,7 +298,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -309,10 +309,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/product-subagent-codex/tool-schemas.expected.json

@@ -133,7 +133,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -231,7 +231,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -245,7 +245,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -277,7 +277,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -288,10 +288,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/pty-tools/tool-schemas.expected.json

@@ -133,7 +133,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -231,7 +231,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -245,7 +245,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -256,7 +256,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -267,10 +267,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/read-image/tool-schemas.expected.json

@@ -133,7 +133,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -247,7 +247,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -261,7 +261,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -272,7 +272,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -283,10 +283,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/session-query-spill/tool-schemas.expected.json

@@ -133,7 +133,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -435,7 +435,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -449,7 +449,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -460,7 +460,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -471,10 +471,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/subagent-child-question-rejection/tool-schemas.expected.json

@@ -196,7 +196,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -294,7 +294,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -308,7 +308,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -319,7 +319,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -330,10 +330,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/subagent-continuable-inheritance/input.json

@@ -14,6 +14,13 @@
    "op": "waitForSubagentTurnEnd",
    "child": 1,
    "minimumTurn": 1
+  },
+  {
+   "op": "waitForTurnStart",
+   "minimumTurn": 2
+  },
+  {
+   "op": "waitForTurnEnd"
   }
  ]
 }

examples/acp-agent/tests/snapshots/subagent-continuable-inheritance/session.jsonl

@@ -27,3 +27,16 @@
 {"type":"assistant/message","seq":25,"time":1786333735904,"data":{"turn":1,"step":2,"message":{"role":"assistant","content":[{"type":"text","text":"DONE"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"4057a08e-b50e-45e7-beb0-c74485f2b7d6"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[20,21,22,23,24],"surfaceOp":"append"}
 {"type":"step/end","seq":26,"time":1786333735904,"data":{"turn":1,"step":2}}
 {"type":"turn/end","seq":27,"time":1786333735904,"data":{"turn":1,"reason":{"kind":"completed"}}}
+{"type":"agent/inbox/spliced","seq":28,"time":1786374357751,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Background subagent 33333333-3333-4333-8333-333333333333 finished and will do no further work unless you send it more."},{"type":"text","text":"Its closing message:"},{"type":"text","text":"CHILD_OK"}],"source":{"kind":"subagent-settled","form":"notice","summary":"Background subagent 33333333-3333-4333-8333-333333333333 finished and will do no further work unless you send it more.","senderSessionId":"33333333-3333-4333-8333-333333333333"},"role":"user","id":"e0bd4902-daba-4e23-bfcb-9e102fdd203d"}]}}
+{"type":"turn/start","seq":29,"time":1786374357751,"data":{"turn":2}}
+{"type":"agent/inbox/spliced","seq":30,"time":1786374357751,"data":{"target":"next-turn","start":0,"removedCount":1,"inserted":[]}}
+{"type":"step/start","seq":31,"time":1786374357758,"data":{"turn":2,"step":1}}
+{"type":"user/message","seq":32,"time":1786374357758,"data":{"content":[{"type":"text","text":"Background subagent 33333333-3333-4333-8333-333333333333 finished and will do no further work unless you send it more."},{"type":"text","text":"Its closing message:"},{"type":"text","text":"CHILD_OK"}],"source":{"kind":"subagent-settled","form":"notice","summary":"Background subagent 33333333-3333-4333-8333-333333333333 finished and will do no further work unless you send it more.","senderSessionId":"33333333-3333-4333-8333-333333333333"},"role":"user","id":"e0bd4902-daba-4e23-bfcb-9e102fdd203d"},"surfaceOp":"append"}
+{"type":"assistant/chunk","seq":33,"time":1786374357764,"data":{"turn":2,"step":1,"chunk":{"type":"block-start","index":0,"blockType":"text"}}}
+{"type":"assistant/chunk","seq":34,"time":1786374357764,"data":{"turn":2,"step":1,"chunk":{"type":"text-delta","index":0,"text":"SUBAGENT_SETTLED_NOTED"}}}
+{"type":"assistant/chunk","seq":35,"time":1786374357764,"data":{"turn":2,"step":1,"chunk":{"type":"block-end","index":0,"block":{"type":"text","text":"SUBAGENT_SETTLED_NOTED"}}}}
+{"type":"assistant/chunk","seq":36,"time":1786374357764,"data":{"turn":2,"step":1,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
+{"type":"assistant/chunk","seq":37,"time":1786374357764,"data":{"turn":2,"step":1,"chunk":{"type":"finish","reason":{"kind":"stop"}}}}
+{"type":"assistant/message","seq":38,"time":1786374357764,"data":{"turn":2,"step":1,"message":{"role":"assistant","content":[{"type":"text","text":"SUBAGENT_SETTLED_NOTED"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"bbe5ef7b-2a3a-47f4-8475-60945b31a373"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[33,34,35,36,37],"surfaceOp":"append"}
+{"type":"step/end","seq":39,"time":1786374357765,"data":{"turn":2,"step":1}}
+{"type":"turn/end","seq":40,"time":1786374357765,"data":{"turn":2,"reason":{"kind":"completed"}}}

examples/acp-agent/tests/snapshots/subagent-continuable-inheritance/stdout.expected.jsonl

@@ -2,3 +2,4 @@
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}"}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"DONE"}}}}
 {"jsonrpc":"2.0","id":3,"result":{"stopReason":"end_turn"}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"SUBAGENT_SETTLED_NOTED"}}}}

examples/acp-agent/tests/snapshots/subagent-continuable-inheritance/system-prompt.1.expected.md

@@ -0,0 +1,24 @@
+You are an AI agent powered by the DeepSeek Harness SDK.
+
+You are a coding assistant powered by the deepseek-v4-flash model. Your working directory is {{cwd}}. Your bash tool runs under a file sandbox — a `[sandbox: file access denied …]` result is policy, not a command bug.
+
+Verify your work by running the code or tests. Keep answers brief and factual.
+
+
+Use the read tool — not shell commands like cat — to inspect text files. Results include line numbers. Use offset and limit to continue reading large files.
+
+Use the write tool to create files or completely replace file contents. Existing files are overwritten, so read an existing file first (the default fs-policy requires it) and prefer edit for targeted changes.
+
+Use the edit tool for targeted changes to existing UTF-8 text files. It replaces literal old_string with new_string; by default old_string must appear exactly once. If old_string appears multiple times, provide a more specific old_string or set replace_all to true. Read the file first (the default fs-policy requires it), unless you just created or edited it in this session.
+
+Check the [exit code: N] marker on every bash result; investigate failures before moving on.
+
+Track every background task id you start. You are notified in-session when a task finishes — do not busy-poll or sleep on one; keep working on independent steps and do not duplicate a running task's work. Before giving a final answer, collect every still-relevant task with task_output (set wait: true only when you are genuinely blocked on it), and task_kill tasks that stopped mattering.
+
+Use goal tools for one long-running completion objective in the current session. create_goal may infer goal intent from a direct human request in any language; do not create a goal for routine single-turn work. Call get_goal before update_goal and copy its exact goal_id and revision. After session resume or fork, an active goal is disarmed: when a human asks to continue or resume in any wording or language, use update_goal action resume to rearm it. Mark complete only when the objective is actually achieved. Mark blocked only after the same blocking condition persists for at least 3 consecutive goal rounds, and report that concrete condition in blocked_reason; difficulty, uncertainty, or useful remaining work is not blocked.
+
+Use the workflow tool ONLY when the user explicitly asks for a workflow or for large multi-agent orchestration: you write a JavaScript script (the tool description documents the exact format) that fans work out across many subagents with phases and structured results. For one or two delegations, prefer plain subagent calls.
+
+Use the ralph tool ONLY when the direct human explicitly asks for a Ralph loop or fresh-agent iterative execution. Each Ralph round starts a fresh child with no conversation seed and uses the shared workspace as durable memory. Completion and blockers are worker reports, not independent evaluation. Use same-session goal tools for ordinary long-running objectives, and plain subagents or workflows for bounded delegation and fan-out.
+
+Deliver your result with the report tool before you finish: call it once with a self-contained answer. The agent that started you shares your workspace but does not automatically receive your transcript, tool output, or reasoning, so a closing remark such as "done" leaves it nothing it can use. Report earlier as well whenever a partial finding changes what that agent should do next; reporting never ends your turn.

examples/acp-agent/tests/snapshots/subagent-continuable-inheritance/tool-schemas.1.expected.json

@@ -133,7 +133,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -194,13 +194,13 @@
     },
     {
       "name": "report",
-      "description": "Report selected content to the agent that started you. Call this zero or more times for progress, findings, or a final answer. Reporting does not end your turn or finish your work, and only your direct parent receives it. A failed call may still have arrived, so do not blindly repeat it.",
+      "description": "Report selected content to the agent that started you. Call this once before you finish, with a self-contained final result, and earlier for progress or findings that change what that agent does next. That agent shares your workspace but does not automatically receive your transcript, tool output, or reasoning, so finishing your work is not itself a result. Reporting does not end your turn or finish your work, and only your direct parent receives it. A failed call may still have arrived, so do not blindly repeat it.",
       "parameters": {
         "type": "object",
         "properties": {
           "output": {
             "type": "string",
-            "description": "Self-contained content for your parent; it does not see your private work."
+            "description": "Actionable content for your parent; summarize conclusions and reference relevant shared paths."
           }
         },
         "required": [
@@ -247,7 +247,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -261,7 +261,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -272,7 +272,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -283,10 +283,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/subagent-continuable/input.json

@@ -10,6 +10,17 @@
       "op": "prompt",
       "text": "Follow these steps exactly, then stop. 1. Call the subagent tool once with run_in_background set to true, description 'Reply with CHILD_OK', and prompt 'Reply with exactly the word CHILD_OK and nothing else.'. 2. Call send_message twice in a row, both with the subagent id from step 1: first with message 'Now reply with exactly SECOND_OK.', then with message 'Now reply with exactly THIRD_OK.'. 3. Call send_message with subagent_id exactly '22222222-2222-4222-8222-222222222222' (a subagent that does not exist) and message 'Please continue.', and observe that it fails. 4. Reply with the single word DONE. Do not use the bash tool."
     },
-    { "op": "waitForSubagentTurnEnd", "child": 1, "minimumTurn": 3 }
+    {
+      "op": "waitForSubagentTurnEnd",
+      "child": 1,
+      "minimumTurn": 3
+    },
+    {
+      "op": "waitForTurnStart",
+      "minimumTurn": 2
+    },
+    {
+      "op": "waitForTurnEnd"
+    }
   ]
 }

examples/acp-agent/tests/snapshots/subagent-continuable/session.jsonl

@@ -1,10 +1,10 @@
 {"type":"session","version":0,"id":"11111111-1111-4111-8111-111111111111","createdAt":1789000000000,"cwd":"{{cwd}}","delegationDepth":0}
-{"type":"agent/inbox/spliced","seq":0,"time":1785730451297,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Follow these steps exactly, then stop. 1. Call the subagent tool once with run_in_background set to true, description 'Reply with CHILD_OK', and prompt 'Reply with exactly the word CHILD_OK and nothing else.'. 2. Call send_message twice in a row, both with the subagent id from step 1: first with message 'Now reply with exactly SECOND_OK.', then with message 'Now reply with exactly THIRD_OK.'. 3. Call send_message with subagent_id exactly '22222222-2222-4222-8222-222222222222' (a subagent that does not exist) and message 'Please continue.', and observe that it fails. 4. Reply with the single word DONE. Do not use the bash tool."}],"source":{"kind":"user"},"role":"user","id":"125665d3-8c03-4190-b4f9-c27d61d245f4"}]}}
+{"type":"agent/inbox/spliced","seq":0,"time":1785730451297,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Follow these steps exactly, then stop. 1. Call the subagent tool once with run_in_background set to true, description 'Reply with CHILD_OK', and prompt 'Reply with exactly the word CHILD_OK and nothing else.'. 2. Call send_message twice in a row, both with the subagent id from step 1: first with message 'Now reply with exactly SECOND_OK.', then with message 'Now reply with exactly THIRD_OK.'. 3. Call send_message with subagent_id exactly '22222222-2222-4222-8222-222222222222' (a subagent that does not exist) and message 'Please continue.', and observe that it fails. 4. Reply with the single word DONE. Do not use the bash tool."}],"source":{"kind":"user"},"role":"user","id":"579d3d6d-a57e-4d55-9b48-05832a79d9f8"}]}}
 {"type":"turn/start","seq":1,"time":1785821408972,"data":{"turn":1}}
 {"type":"agent/inbox/spliced","seq":2,"time":1785821408972,"data":{"target":"next-turn","start":0,"removedCount":1,"inserted":[]}}
 {"type":"step/start","seq":3,"time":1785730451327,"data":{"turn":1,"step":1}}
-{"type":"user/message","seq":4,"time":1785730451327,"data":{"content":[{"type":"text","text":"Follow these steps exactly, then stop. 1. Call the subagent tool once with run_in_background set to true, description 'Reply with CHILD_OK', and prompt 'Reply with exactly the word CHILD_OK and nothing else.'. 2. Call send_message twice in a row, both with the subagent id from step 1: first with message 'Now reply with exactly SECOND_OK.', then with message 'Now reply with exactly THIRD_OK.'. 3. Call send_message with subagent_id exactly '22222222-2222-4222-8222-222222222222' (a subagent that does not exist) and message 'Please continue.', and observe that it fails. 4. Reply with the single word DONE. Do not use the bash tool."}],"source":{"kind":"user"},"role":"user","id":"125665d3-8c03-4190-b4f9-c27d61d245f4"},"surfaceOp":"append"}
-{"type":"user/message","seq":5,"time":1785730451328,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."}]},"role":"user","id":"533e9513-a329-4a36-9a8d-ddaf544b57c3"},"surfaceOp":"append"}
+{"type":"user/message","seq":4,"time":1785730451327,"data":{"content":[{"type":"text","text":"Follow these steps exactly, then stop. 1. Call the subagent tool once with run_in_background set to true, description 'Reply with CHILD_OK', and prompt 'Reply with exactly the word CHILD_OK and nothing else.'. 2. Call send_message twice in a row, both with the subagent id from step 1: first with message 'Now reply with exactly SECOND_OK.', then with message 'Now reply with exactly THIRD_OK.'. 3. Call send_message with subagent_id exactly '22222222-2222-4222-8222-222222222222' (a subagent that does not exist) and message 'Please continue.', and observe that it fails. 4. Reply with the single word DONE. Do not use the bash tool."}],"source":{"kind":"user"},"role":"user","id":"579d3d6d-a57e-4d55-9b48-05832a79d9f8"},"surfaceOp":"append"}
+{"type":"user/message","seq":5,"time":1785730451328,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."}]},"role":"user","id":"c4f5f7ed-1c11-4f31-923f-3142c79f0c2c"},"surfaceOp":"append"}
 {"type":"session/title","seq":6,"time":1785730451328,"data":{"title":"Follow these steps exactly, then","messageSeqs":[4],"source":{"kind":"fallback"}}}
 {"type":"request/header","seq":7,"time":1785730451329,"data":{"header":{"config":{"provider":"deepseek-official","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"initial"}}
 {"type":"request/context","seq":8,"time":1785730451329,"data":{"provider":"deepseek-official","model":"deepseek-v4-flash"}}
@@ -13,9 +13,9 @@
 {"type":"assistant/chunk","seq":11,"time":1785544945188,"data":{"turn":1,"step":1,"chunk":{"type":"block-end","index":0,"block":{"type":"tool-call","id":"call_bg_start","name":"subagent","arguments":"{\"description\": \"Reply with CHILD_OK\", \"prompt\": \"Reply with exactly the word CHILD_OK and nothing else.\", \"run_in_background\": true}"}}}}
 {"type":"assistant/chunk","seq":12,"time":1785544945188,"data":{"turn":1,"step":1,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
 {"type":"assistant/chunk","seq":13,"time":1785730451338,"data":{"turn":1,"step":1,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
-{"type":"assistant/message","seq":14,"time":1785730451338,"data":{"turn":1,"step":1,"message":{"role":"assistant","content":[{"type":"tool-call","id":"call_bg_start","name":"subagent","arguments":"{\"description\": \"Reply with CHILD_OK\", \"prompt\": \"Reply with exactly the word CHILD_OK and nothing else.\", \"run_in_background\": true}"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"4a2c2f8b-66be-4860-9bbf-b83feb56009e"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[9,10,11,12,13],"surfaceOp":"append"}
+{"type":"assistant/message","seq":14,"time":1785730451338,"data":{"turn":1,"step":1,"message":{"role":"assistant","content":[{"type":"tool-call","id":"call_bg_start","name":"subagent","arguments":"{\"description\": \"Reply with CHILD_OK\", \"prompt\": \"Reply with exactly the word CHILD_OK and nothing else.\", \"run_in_background\": true}"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"680da987-6d29-4141-b83d-af57b050c712"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[9,10,11,12,13],"surfaceOp":"append"}
 {"type":"tool/call","seq":15,"time":1785730451338,"data":{"turn":1,"step":1,"callId":"call_bg_start","name":"subagent","arguments":"{\"description\": \"Reply with CHILD_OK\", \"prompt\": \"Reply with exactly the word CHILD_OK and nothing else.\", \"run_in_background\": true}"}}
-{"type":"tool/result","seq":16,"time":1785730451348,"data":{"turn":1,"step":1,"message":{"source":{"kind":"tool","callId":"call_bg_start"},"content":[{"type":"tool-result","toolCallId":"call_bg_start","content":[{"type":"text","text":"started subagent 33333333-3333-4333-8333-333333333333"}],"isError":false}],"role":"user","id":"b54a0d61-4233-40f1-ab3a-3eb58e1b0c61"}},"sourceEventSeqs":[15],"surfaceOp":"append"}
+{"type":"tool/result","seq":16,"time":1785730451348,"data":{"turn":1,"step":1,"message":{"source":{"kind":"tool","callId":"call_bg_start"},"content":[{"type":"tool-result","toolCallId":"call_bg_start","content":[{"type":"text","text":"started subagent 33333333-3333-4333-8333-333333333333"}],"isError":false}],"role":"user","id":"7825edb2-080e-49c1-ba74-ad69d16bf566"}},"sourceEventSeqs":[15],"surfaceOp":"append"}
 {"type":"step/end","seq":17,"time":1785730451348,"data":{"turn":1,"step":1}}
 {"type":"step/start","seq":18,"time":1785730451360,"data":{"turn":1,"step":2}}
 {"type":"assistant/chunk","seq":19,"time":1789000000019,"data":{"turn":1,"step":2,"chunk":{"type":"block-start","index":0,"blockType":"tool-call"}}}
@@ -23,9 +23,9 @@
 {"type":"assistant/chunk","seq":21,"time":1785544945212,"data":{"turn":1,"step":2,"chunk":{"type":"block-end","index":0,"block":{"type":"tool-call","id":"call_followup_1","name":"send_message","arguments":"{\"subagent_id\": \"33333333-3333-4333-8333-333333333333\", \"message\": \"Now reply with exactly SECOND_OK.\"}"}}}}
 {"type":"assistant/chunk","seq":22,"time":1785544945212,"data":{"turn":1,"step":2,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
 {"type":"assistant/chunk","seq":23,"time":1785730451364,"data":{"turn":1,"step":2,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
-{"type":"assistant/message","seq":24,"time":1785730451364,"data":{"turn":1,"step":2,"message":{"role":"assistant","content":[{"type":"tool-call","id":"call_followup_1","name":"send_message","arguments":"{\"subagent_id\": \"33333333-3333-4333-8333-333333333333\", \"message\": \"Now reply with exactly SECOND_OK.\"}"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"398dea92-a100-4b2f-a9e1-72629def132d"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[19,20,21,22,23],"surfaceOp":"append"}
+{"type":"assistant/message","seq":24,"time":1785730451364,"data":{"turn":1,"step":2,"message":{"role":"assistant","content":[{"type":"tool-call","id":"call_followup_1","name":"send_message","arguments":"{\"subagent_id\": \"33333333-3333-4333-8333-333333333333\", \"message\": \"Now reply with exactly SECOND_OK.\"}"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"ef6eadc7-165e-4705-b865-3889f0af0f36"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[19,20,21,22,23],"surfaceOp":"append"}
 {"type":"tool/call","seq":25,"time":1785730451365,"data":{"turn":1,"step":2,"callId":"call_followup_1","name":"send_message","arguments":"{\"subagent_id\": \"33333333-3333-4333-8333-333333333333\", \"message\": \"Now reply with exactly SECOND_OK.\"}"}}
-{"type":"tool/result","seq":26,"time":1785730451377,"data":{"turn":1,"step":2,"message":{"source":{"kind":"tool","callId":"call_followup_1"},"content":[{"type":"tool-result","toolCallId":"call_followup_1","content":[{"type":"text","text":"message queued as the next turn for subagent 33333333-3333-4333-8333-333333333333"}],"isError":false}],"role":"user","id":"45b388fd-6a48-4a02-9f3b-1d642e797c71"}},"sourceEventSeqs":[25],"surfaceOp":"append"}
+{"type":"tool/result","seq":26,"time":1785730451377,"data":{"turn":1,"step":2,"message":{"source":{"kind":"tool","callId":"call_followup_1"},"content":[{"type":"tool-result","toolCallId":"call_followup_1","content":[{"type":"text","text":"message queued as the next turn for subagent 33333333-3333-4333-8333-333333333333"}],"isError":false}],"role":"user","id":"ac1214a5-1d91-4fab-8f96-833baca114f8"}},"sourceEventSeqs":[25],"surfaceOp":"append"}
 {"type":"step/end","seq":27,"time":1785730451377,"data":{"turn":1,"step":2}}
 {"type":"step/start","seq":28,"time":1785730451390,"data":{"turn":1,"step":3}}
 {"type":"assistant/chunk","seq":29,"time":1789000000029,"data":{"turn":1,"step":3,"chunk":{"type":"block-start","index":0,"blockType":"tool-call"}}}
@@ -33,9 +33,9 @@
 {"type":"assistant/chunk","seq":31,"time":1785544945241,"data":{"turn":1,"step":3,"chunk":{"type":"block-end","index":0,"block":{"type":"tool-call","id":"call_followup_2","name":"send_message","arguments":"{\"subagent_id\": \"33333333-3333-4333-8333-333333333333\", \"message\": \"Now reply with exactly THIRD_OK.\"}"}}}}
 {"type":"assistant/chunk","seq":32,"time":1785544945242,"data":{"turn":1,"step":3,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
 {"type":"assistant/chunk","seq":33,"time":1785730451394,"data":{"turn":1,"step":3,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
-{"type":"assistant/message","seq":34,"time":1785730451394,"data":{"turn":1,"step":3,"message":{"role":"assistant","content":[{"type":"tool-call","id":"call_followup_2","name":"send_message","arguments":"{\"subagent_id\": \"33333333-3333-4333-8333-333333333333\", \"message\": \"Now reply with exactly THIRD_OK.\"}"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"f56cec19-e761-4c77-9237-07d12d334275"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[29,30,31,32,33],"surfaceOp":"append"}
+{"type":"assistant/message","seq":34,"time":1785730451394,"data":{"turn":1,"step":3,"message":{"role":"assistant","content":[{"type":"tool-call","id":"call_followup_2","name":"send_message","arguments":"{\"subagent_id\": \"33333333-3333-4333-8333-333333333333\", \"message\": \"Now reply with exactly THIRD_OK.\"}"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"33939813-0792-4ac5-8864-ec62a4ddff8e"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[29,30,31,32,33],"surfaceOp":"append"}
 {"type":"tool/call","seq":35,"time":1785730451395,"data":{"turn":1,"step":3,"callId":"call_followup_2","name":"send_message","arguments":"{\"subagent_id\": \"33333333-3333-4333-8333-333333333333\", \"message\": \"Now reply with exactly THIRD_OK.\"}"}}
-{"type":"tool/result","seq":36,"time":1785730451406,"data":{"turn":1,"step":3,"message":{"source":{"kind":"tool","callId":"call_followup_2"},"content":[{"type":"tool-result","toolCallId":"call_followup_2","content":[{"type":"text","text":"message queued as the next turn for subagent 33333333-3333-4333-8333-333333333333"}],"isError":false}],"role":"user","id":"193df31b-de9a-4723-b2b1-c7c96a8eaee4"}},"sourceEventSeqs":[35],"surfaceOp":"append"}
+{"type":"tool/result","seq":36,"time":1785730451406,"data":{"turn":1,"step":3,"message":{"source":{"kind":"tool","callId":"call_followup_2"},"content":[{"type":"tool-result","toolCallId":"call_followup_2","content":[{"type":"text","text":"message queued as the next turn for subagent 33333333-3333-4333-8333-333333333333"}],"isError":false}],"role":"user","id":"a6f64c64-f50c-47cd-a6b3-a3b57d3dc83d"}},"sourceEventSeqs":[35],"surfaceOp":"append"}
 {"type":"step/end","seq":37,"time":1785730451406,"data":{"turn":1,"step":3}}
 {"type":"step/start","seq":38,"time":1785730451419,"data":{"turn":1,"step":4}}
 {"type":"assistant/chunk","seq":39,"time":1789000000039,"data":{"turn":1,"step":4,"chunk":{"type":"block-start","index":0,"blockType":"tool-call"}}}
@@ -43,9 +43,9 @@
 {"type":"assistant/chunk","seq":41,"time":1785544945273,"data":{"turn":1,"step":4,"chunk":{"type":"block-end","index":0,"block":{"type":"tool-call","id":"call_followup_unknown","name":"send_message","arguments":"{\"subagent_id\": \"22222222-2222-4222-8222-222222222222\", \"message\": \"Please continue.\"}"}}}}
 {"type":"assistant/chunk","seq":42,"time":1785544945273,"data":{"turn":1,"step":4,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
 {"type":"assistant/chunk","seq":43,"time":1785730451424,"data":{"turn":1,"step":4,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
-{"type":"assistant/message","seq":44,"time":1785730451424,"data":{"turn":1,"step":4,"message":{"role":"assistant","content":[{"type":"tool-call","id":"call_followup_unknown","name":"send_message","arguments":"{\"subagent_id\": \"22222222-2222-4222-8222-222222222222\", \"message\": \"Please continue.\"}"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"cbf54e23-fb96-45cc-b629-b9cb48fc9876"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[39,40,41,42,43],"surfaceOp":"append"}
+{"type":"assistant/message","seq":44,"time":1785730451424,"data":{"turn":1,"step":4,"message":{"role":"assistant","content":[{"type":"tool-call","id":"call_followup_unknown","name":"send_message","arguments":"{\"subagent_id\": \"22222222-2222-4222-8222-222222222222\", \"message\": \"Please continue.\"}"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"95eab91d-b103-4033-8e2e-c9c93b1b0211"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[39,40,41,42,43],"surfaceOp":"append"}
 {"type":"tool/call","seq":45,"time":1785730451425,"data":{"turn":1,"step":4,"callId":"call_followup_unknown","name":"send_message","arguments":"{\"subagent_id\": \"22222222-2222-4222-8222-222222222222\", \"message\": \"Please continue.\"}"}}
-{"type":"tool/result","seq":46,"time":1785730451437,"data":{"turn":1,"step":4,"message":{"source":{"kind":"tool","callId":"call_followup_unknown"},"content":[{"type":"tool-result","toolCallId":"call_followup_unknown","content":[{"type":"text","text":"Error: subagent \"22222222-2222-4222-8222-222222222222\" is unavailable"}],"isError":true}],"role":"user","id":"d5d961af-c171-40b6-87a1-33d2c14740a7"},"error":{"name":"SubagentError","code":"NOT_RESUMABLE"}},"sourceEventSeqs":[45],"surfaceOp":"append"}
+{"type":"tool/result","seq":46,"time":1785730451437,"data":{"turn":1,"step":4,"message":{"source":{"kind":"tool","callId":"call_followup_unknown"},"content":[{"type":"tool-result","toolCallId":"call_followup_unknown","content":[{"type":"text","text":"Error: subagent \"22222222-2222-4222-8222-222222222222\" is unavailable"}],"isError":true}],"role":"user","id":"8a095e4b-3059-420d-856f-1cbd20b6a2e2"},"error":{"name":"SubagentError","code":"NOT_RESUMABLE"}},"sourceEventSeqs":[45],"surfaceOp":"append"}
 {"type":"step/end","seq":47,"time":1785730451437,"data":{"turn":1,"step":4}}
 {"type":"step/start","seq":48,"time":1785730451450,"data":{"turn":1,"step":5}}
 {"type":"assistant/chunk","seq":49,"time":1785394678779,"data":{"turn":1,"step":5,"chunk":{"type":"block-start","index":0,"blockType":"text"}}}
@@ -53,6 +53,19 @@
 {"type":"assistant/chunk","seq":51,"time":1785544945303,"data":{"turn":1,"step":5,"chunk":{"type":"block-end","index":0,"block":{"type":"text","text":"DONE"}}}}
 {"type":"assistant/chunk","seq":52,"time":1785544945303,"data":{"turn":1,"step":5,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
 {"type":"assistant/chunk","seq":53,"time":1785730451453,"data":{"turn":1,"step":5,"chunk":{"type":"finish","reason":{"kind":"stop"}}}}
-{"type":"assistant/message","seq":54,"time":1785730451453,"data":{"turn":1,"step":5,"message":{"role":"assistant","content":[{"type":"text","text":"DONE"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"fbea6b64-84cf-4411-abec-48d26b3801da"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[49,50,51,52,53],"surfaceOp":"append"}
+{"type":"assistant/message","seq":54,"time":1785730451453,"data":{"turn":1,"step":5,"message":{"role":"assistant","content":[{"type":"text","text":"DONE"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"eb51ecb3-3347-4216-ad4e-c2130c43ecfc"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[49,50,51,52,53],"surfaceOp":"append"}
 {"type":"step/end","seq":55,"time":1785730451454,"data":{"turn":1,"step":5}}
 {"type":"turn/end","seq":56,"time":1785730451454,"data":{"turn":1,"reason":{"kind":"completed"}}}
+{"type":"agent/inbox/spliced","seq":57,"time":1786011346660,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Background subagent 33333333-3333-4333-8333-333333333333 failed before it finished."},{"type":"text","text":"Its closing message:"},{"type":"text","text":"SECOND_OK"}],"source":{"kind":"subagent-settled","form":"notice","summary":"Background subagent 33333333-3333-4333-8333-333333333333 failed before it finished.","senderSessionId":"33333333-3333-4333-8333-333333333333"},"role":"user","id":"2cf0afd2-ee6e-4a3f-a35a-2fd4d5b665ca"}]}}
+{"type":"turn/start","seq":58,"time":1786011346660,"data":{"turn":2}}
+{"type":"agent/inbox/spliced","seq":59,"time":1786011346660,"data":{"target":"next-turn","start":0,"removedCount":1,"inserted":[]}}
+{"type":"step/start","seq":60,"time":1786012466689,"data":{"turn":2,"step":1}}
+{"type":"user/message","seq":61,"time":1786012466689,"data":{"content":[{"type":"text","text":"Background subagent 33333333-3333-4333-8333-333333333333 failed before it finished."},{"type":"text","text":"Its closing message:"},{"type":"text","text":"SECOND_OK"}],"source":{"kind":"subagent-settled","form":"notice","summary":"Background subagent 33333333-3333-4333-8333-333333333333 failed before it finished.","senderSessionId":"33333333-3333-4333-8333-333333333333"},"role":"user","id":"2cf0afd2-ee6e-4a3f-a35a-2fd4d5b665ca"},"surfaceOp":"append"}
+{"type":"assistant/chunk","seq":62,"time":1786012466693,"data":{"turn":2,"step":1,"chunk":{"type":"block-start","index":0,"blockType":"text"}}}
+{"type":"assistant/chunk","seq":63,"time":1786012466693,"data":{"turn":2,"step":1,"chunk":{"type":"text-delta","index":0,"text":"SUBAGENT_SETTLED_NOTED"}}}
+{"type":"assistant/chunk","seq":64,"time":1786012466693,"data":{"turn":2,"step":1,"chunk":{"type":"block-end","index":0,"block":{"type":"text","text":"SUBAGENT_SETTLED_NOTED"}}}}
+{"type":"assistant/chunk","seq":65,"time":1786012466693,"data":{"turn":2,"step":1,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
+{"type":"assistant/chunk","seq":66,"time":1786012466693,"data":{"turn":2,"step":1,"chunk":{"type":"finish","reason":{"kind":"stop"}}}}
+{"type":"assistant/message","seq":67,"time":1786333283620,"data":{"turn":2,"step":1,"message":{"role":"assistant","content":[{"type":"text","text":"SUBAGENT_SETTLED_NOTED"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"758adcee-9284-4889-86a2-0181a278a754"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[62,63,64,65,66],"surfaceOp":"append"}
+{"type":"step/end","seq":68,"time":1786333283620,"data":{"turn":2,"step":1}}
+{"type":"turn/end","seq":69,"time":1786333283620,"data":{"turn":2,"reason":{"kind":"completed"}}}

examples/acp-agent/tests/snapshots/subagent-continuable/stdout.expected.jsonl

@@ -2,3 +2,4 @@
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}"}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"DONE"}}}}
 {"jsonrpc":"2.0","id":3,"result":{"stopReason":"end_turn"}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"SUBAGENT_SETTLED_NOTED"}}}}

examples/acp-agent/tests/snapshots/subagent-continuable/system-prompt.1.expected.md

@@ -0,0 +1,24 @@
+You are an AI agent powered by the DeepSeek Harness SDK.
+
+You are a coding assistant powered by the deepseek-v4-flash model. Your working directory is {{cwd}}. Your bash tool runs under a file sandbox — a `[sandbox: file access denied …]` result is policy, not a command bug.
+
+Verify your work by running the code or tests. Keep answers brief and factual.
+
+
+Use the read tool — not shell commands like cat — to inspect text files. Results include line numbers. Use offset and limit to continue reading large files.
+
+Use the write tool to create files or completely replace file contents. Existing files are overwritten, so read an existing file first (the default fs-policy requires it) and prefer edit for targeted changes.
+
+Use the edit tool for targeted changes to existing UTF-8 text files. It replaces literal old_string with new_string; by default old_string must appear exactly once. If old_string appears multiple times, provide a more specific old_string or set replace_all to true. Read the file first (the default fs-policy requires it), unless you just created or edited it in this session.
+
+Check the [exit code: N] marker on every bash result; investigate failures before moving on.
+
+Track every background task id you start. You are notified in-session when a task finishes — do not busy-poll or sleep on one; keep working on independent steps and do not duplicate a running task's work. Before giving a final answer, collect every still-relevant task with task_output (set wait: true only when you are genuinely blocked on it), and task_kill tasks that stopped mattering.
+
+Use goal tools for one long-running completion objective in the current session. create_goal may infer goal intent from a direct human request in any language; do not create a goal for routine single-turn work. Call get_goal before update_goal and copy its exact goal_id and revision. After session resume or fork, an active goal is disarmed: when a human asks to continue or resume in any wording or language, use update_goal action resume to rearm it. Mark complete only when the objective is actually achieved. Mark blocked only after the same blocking condition persists for at least 3 consecutive goal rounds, and report that concrete condition in blocked_reason; difficulty, uncertainty, or useful remaining work is not blocked.
+
+Use the workflow tool ONLY when the user explicitly asks for a workflow or for large multi-agent orchestration: you write a JavaScript script (the tool description documents the exact format) that fans work out across many subagents with phases and structured results. For one or two delegations, prefer plain subagent calls.
+
+Use the ralph tool ONLY when the direct human explicitly asks for a Ralph loop or fresh-agent iterative execution. Each Ralph round starts a fresh child with no conversation seed and uses the shared workspace as durable memory. Completion and blockers are worker reports, not independent evaluation. Use same-session goal tools for ordinary long-running objectives, and plain subagents or workflows for bounded delegation and fan-out.
+
+Deliver your result with the report tool before you finish: call it once with a self-contained answer. The agent that started you shares your workspace but does not automatically receive your transcript, tool output, or reasoning, so a closing remark such as "done" leaves it nothing it can use. Report earlier as well whenever a partial finding changes what that agent should do next; reporting never ends your turn.

examples/acp-agent/tests/snapshots/subagent-continuable/tool-schemas.1.expected.json

@@ -133,7 +133,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -194,13 +194,13 @@
     },
     {
       "name": "report",
-      "description": "Report selected content to the agent that started you. Call this zero or more times for progress, findings, or a final answer. Reporting does not end your turn or finish your work, and only your direct parent receives it. A failed call may still have arrived, so do not blindly repeat it.",
+      "description": "Report selected content to the agent that started you. Call this once before you finish, with a self-contained final result, and earlier for progress or findings that change what that agent does next. That agent shares your workspace but does not automatically receive your transcript, tool output, or reasoning, so finishing your work is not itself a result. Reporting does not end your turn or finish your work, and only your direct parent receives it. A failed call may still have arrived, so do not blindly repeat it.",
       "parameters": {
         "type": "object",
         "properties": {
           "output": {
             "type": "string",
-            "description": "Self-contained content for your parent; it does not see your private work."
+            "description": "Actionable content for your parent; summarize conclusions and reference relevant shared paths."
           }
         },
         "required": [
@@ -247,7 +247,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -261,7 +261,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -272,7 +272,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -283,10 +283,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/subagent-depth-two-rejection/session.1.jsonl

@@ -6,7 +6,7 @@
 {"type":"subagent/descriptor","seq":4,"time":1786357533600,"data":{"version":2,"mode":"one-shot","provider":"spawn","label":"Start depth one"}}
 {"type":"step/start","seq":5,"time":1786357533602,"data":{"turn":1,"step":1}}
 {"type":"user/message","seq":6,"time":1785730456014,"data":{"content":[{"type":"text","text":"Call subagent once. Ask that child to attempt one further subagent call, then report the result."}],"source":{"kind":"user"},"role":"user","id":"a8129357-1bde-4cbd-90b4-6b8ad51d52e1"},"surfaceOp":"append"}
-{"type":"user/message","seq":7,"time":1786357533602,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"82a11d62-da49-4ad3-a243-789ea3cd7c08"},"surfaceOp":"append"}
+{"type":"user/message","seq":7,"time":1786357533602,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"d8d6b5bf-db7b-484f-8095-e35915b94274"},"surfaceOp":"append"}
 {"type":"session/title","seq":8,"time":1786357533602,"data":{"title":"Call subagent once. Ask that","messageSeqs":[6],"source":{"kind":"fallback"}}}
 {"type":"request/header","seq":9,"time":1785730456014,"data":{"header":{"config":{"provider":"deepseek-official","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"initial"}}
 {"type":"request/context","seq":10,"time":1785730456014,"data":{"provider":"deepseek-official","model":"deepseek-v4-flash"}}

examples/acp-agent/tests/snapshots/subagent-depth-two-rejection/session.2.jsonl

@@ -6,7 +6,7 @@
 {"type":"subagent/descriptor","seq":4,"time":1786357533628,"data":{"version":2,"mode":"one-shot","provider":"spawn","label":"Start depth two"}}
 {"type":"step/start","seq":5,"time":1786357533630,"data":{"turn":1,"step":1}}
 {"type":"user/message","seq":6,"time":1785730456041,"data":{"content":[{"type":"text","text":"Attempt one subagent call beyond the configured cap, then report the rejection."}],"source":{"kind":"user"},"role":"user","id":"d4dc5a16-e542-4dd9-8e82-e6b7829cfc4b"},"surfaceOp":"append"}
-{"type":"user/message","seq":7,"time":1786357533630,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"d5488efe-eea2-4019-8fcb-7e6e49077d8a"},"surfaceOp":"append"}
+{"type":"user/message","seq":7,"time":1786357533630,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"e9907a11-3d7c-4796-a459-16afd4afde32"},"surfaceOp":"append"}
 {"type":"session/title","seq":8,"time":1786357533630,"data":{"title":"Attempt one subagent call beyond","messageSeqs":[6],"source":{"kind":"fallback"}}}
 {"type":"request/header","seq":9,"time":1785730456041,"data":{"header":{"config":{"provider":"deepseek-official","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"initial"}}
 {"type":"request/context","seq":10,"time":1785730456042,"data":{"provider":"deepseek-official","model":"deepseek-v4-flash"}}

examples/acp-agent/tests/snapshots/subagent-list-agents/input.json

@@ -14,6 +14,13 @@
       "op": "waitForFile",
       "path": ".dsh-snapshot-subagent-settled"
     },
+    {
+      "op": "waitForTurnStart",
+      "minimumTurn": 2
+    },
+    {
+      "op": "waitForTurnEnd"
+    },
     {
       "op": "prompt",
       "text": "Call list_agents once with scope set to descendants and observe the subagent you started. Then call interrupt_agent once with agent_id set to 33333333-3333-4333-8333-333333333333. Then reply with the single word DONE. Do not call any other tool."

examples/acp-agent/tests/snapshots/subagent-list-agents/session.jsonl

@@ -1,10 +1,10 @@
 {"type":"session","version":0,"id":"11111111-1111-4111-8111-111111111111","createdAt":1789000000000,"cwd":"{{cwd}}","delegationDepth":0}
-{"type":"agent/inbox/spliced","seq":0,"time":1785730454756,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Call the subagent tool once with run_in_background set to true, description 'Reply with CHILD_OK', and prompt 'Reply with exactly the word CHILD_OK and nothing else.'. Then reply with the single word STARTED. Do not call any other tool."}],"source":{"kind":"user"},"role":"user","id":"c2febfff-792d-4457-a944-933ff0de0570"}]}}
+{"type":"agent/inbox/spliced","seq":0,"time":1785730454756,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Call the subagent tool once with run_in_background set to true, description 'Reply with CHILD_OK', and prompt 'Reply with exactly the word CHILD_OK and nothing else.'. Then reply with the single word STARTED. Do not call any other tool."}],"source":{"kind":"user"},"role":"user","id":"356b3b62-c8b8-4d2a-84d7-7df1b6e4811e"}]}}
 {"type":"turn/start","seq":1,"time":1785821412725,"data":{"turn":1}}
 {"type":"agent/inbox/spliced","seq":2,"time":1785821412725,"data":{"target":"next-turn","start":0,"removedCount":1,"inserted":[]}}
 {"type":"step/start","seq":3,"time":1785730454783,"data":{"turn":1,"step":1}}
-{"type":"user/message","seq":4,"time":1785730454783,"data":{"content":[{"type":"text","text":"Call the subagent tool once with run_in_background set to true, description 'Reply with CHILD_OK', and prompt 'Reply with exactly the word CHILD_OK and nothing else.'. Then reply with the single word STARTED. Do not call any other tool."}],"source":{"kind":"user"},"role":"user","id":"c2febfff-792d-4457-a944-933ff0de0570"},"surfaceOp":"append"}
-{"type":"user/message","seq":5,"time":1785730454783,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."}]},"role":"user","id":"c9d1f853-56bc-4082-ae08-00d4bcbb04a6"},"surfaceOp":"append"}
+{"type":"user/message","seq":4,"time":1785730454783,"data":{"content":[{"type":"text","text":"Call the subagent tool once with run_in_background set to true, description 'Reply with CHILD_OK', and prompt 'Reply with exactly the word CHILD_OK and nothing else.'. Then reply with the single word STARTED. Do not call any other tool."}],"source":{"kind":"user"},"role":"user","id":"356b3b62-c8b8-4d2a-84d7-7df1b6e4811e"},"surfaceOp":"append"}
+{"type":"user/message","seq":5,"time":1785730454783,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."}]},"role":"user","id":"9be42fb0-f0d0-4ab9-a232-fb753f7db482"},"surfaceOp":"append"}
 {"type":"session/title","seq":6,"time":1785730454783,"data":{"title":"Call the subagent tool once","messageSeqs":[4],"source":{"kind":"fallback"}}}
 {"type":"request/header","seq":7,"time":1785730454784,"data":{"header":{"config":{"provider":"deepseek-official","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"initial"}}
 {"type":"request/context","seq":8,"time":1785730454784,"data":{"provider":"deepseek-official","model":"deepseek-v4-flash"}}
@@ -13,9 +13,9 @@
 {"type":"assistant/chunk","seq":11,"time":1785531795632,"data":{"turn":1,"step":1,"chunk":{"type":"block-end","index":0,"block":{"type":"tool-call","id":"call_bg_start","name":"subagent","arguments":"{\"description\": \"Reply with CHILD_OK\", \"prompt\": \"Reply with exactly the word CHILD_OK and nothing else.\", \"run_in_background\": true}"}}}}
 {"type":"assistant/chunk","seq":12,"time":1785531795632,"data":{"turn":1,"step":1,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
 {"type":"assistant/chunk","seq":13,"time":1785730454793,"data":{"turn":1,"step":1,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
-{"type":"assistant/message","seq":14,"time":1785730454793,"data":{"turn":1,"step":1,"message":{"role":"assistant","content":[{"type":"tool-call","id":"call_bg_start","name":"subagent","arguments":"{\"description\": \"Reply with CHILD_OK\", \"prompt\": \"Reply with exactly the word CHILD_OK and nothing else.\", \"run_in_background\": true}"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"4dda49d6-5d02-456f-ba95-68699662793d"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[9,10,11,12,13],"surfaceOp":"append"}
+{"type":"assistant/message","seq":14,"time":1785730454793,"data":{"turn":1,"step":1,"message":{"role":"assistant","content":[{"type":"tool-call","id":"call_bg_start","name":"subagent","arguments":"{\"description\": \"Reply with CHILD_OK\", \"prompt\": \"Reply with exactly the word CHILD_OK and nothing else.\", \"run_in_background\": true}"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"c8802574-4e43-4ee7-8648-5a132935b5dc"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[9,10,11,12,13],"surfaceOp":"append"}
 {"type":"tool/call","seq":15,"time":1785730454793,"data":{"turn":1,"step":1,"callId":"call_bg_start","name":"subagent","arguments":"{\"description\": \"Reply with CHILD_OK\", \"prompt\": \"Reply with exactly the word CHILD_OK and nothing else.\", \"run_in_background\": true}"}}
-{"type":"tool/result","seq":16,"time":1785730454804,"data":{"turn":1,"step":1,"message":{"source":{"kind":"tool","callId":"call_bg_start"},"content":[{"type":"tool-result","toolCallId":"call_bg_start","content":[{"type":"text","text":"started subagent 33333333-3333-4333-8333-333333333333"}],"isError":false}],"role":"user","id":"7f1fbe79-98b7-410a-af4d-c40d52a366dc"}},"sourceEventSeqs":[15],"surfaceOp":"append"}
+{"type":"tool/result","seq":16,"time":1785730454804,"data":{"turn":1,"step":1,"message":{"source":{"kind":"tool","callId":"call_bg_start"},"content":[{"type":"tool-result","toolCallId":"call_bg_start","content":[{"type":"text","text":"started subagent 33333333-3333-4333-8333-333333333333"}],"isError":false}],"role":"user","id":"c83395ad-93c6-4899-9ae1-8d29f92d4dde"}},"sourceEventSeqs":[15],"surfaceOp":"append"}
 {"type":"step/end","seq":17,"time":1785730454804,"data":{"turn":1,"step":1}}
 {"type":"step/start","seq":18,"time":1785730454814,"data":{"turn":1,"step":2}}
 {"type":"assistant/chunk","seq":19,"time":1789000000017,"data":{"turn":1,"step":2,"chunk":{"type":"block-start","index":0,"blockType":"text"}}}
@@ -23,39 +23,42 @@
 {"type":"assistant/chunk","seq":21,"time":1785531795656,"data":{"turn":1,"step":2,"chunk":{"type":"block-end","index":0,"block":{"type":"text","text":"STARTED"}}}}
 {"type":"assistant/chunk","seq":22,"time":1785531795656,"data":{"turn":1,"step":2,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
 {"type":"assistant/chunk","seq":23,"time":1785730454820,"data":{"turn":1,"step":2,"chunk":{"type":"finish","reason":{"kind":"stop"}}}}
-{"type":"assistant/message","seq":24,"time":1785730454820,"data":{"turn":1,"step":2,"message":{"role":"assistant","content":[{"type":"text","text":"STARTED"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"2ee459fa-21f9-48c6-a42e-3c38eca1e4c9"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[19,20,21,22,23],"surfaceOp":"append"}
+{"type":"assistant/message","seq":24,"time":1785730454820,"data":{"turn":1,"step":2,"message":{"role":"assistant","content":[{"type":"text","text":"STARTED"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"1fefe87b-4c3c-49b0-860c-8097193f9567"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[19,20,21,22,23],"surfaceOp":"append"}
 {"type":"step/end","seq":25,"time":1785730454821,"data":{"turn":1,"step":2}}
 {"type":"turn/end","seq":26,"time":1785730454821,"data":{"turn":1,"reason":{"kind":"completed"}}}
-{"type":"agent/inbox/spliced","seq":27,"time":1785730454857,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Call list_agents once with scope set to descendants and observe the subagent you started. Then call interrupt_agent once with agent_id set to 33333333-3333-4333-8333-333333333333. Then reply with the single word DONE. Do not call any other tool."}],"source":{"kind":"user"},"role":"user","id":"3bcac2a3-e0db-465b-94b4-4e2761236475"}]}}
-{"type":"turn/start","seq":28,"time":1785821412840,"data":{"turn":2}}
-{"type":"agent/inbox/spliced","seq":29,"time":1785821412840,"data":{"target":"next-turn","start":0,"removedCount":1,"inserted":[]}}
-{"type":"step/start","seq":30,"time":1785730454863,"data":{"turn":2,"step":1}}
-{"type":"user/message","seq":31,"time":1785730454863,"data":{"content":[{"type":"text","text":"Call list_agents once with scope set to descendants and observe the subagent you started. Then call interrupt_agent once with agent_id set to 33333333-3333-4333-8333-333333333333. Then reply with the single word DONE. Do not call any other tool."}],"source":{"kind":"user"},"role":"user","id":"3bcac2a3-e0db-465b-94b4-4e2761236475"},"surfaceOp":"append"}
-{"type":"assistant/chunk","seq":32,"time":1785531795686,"data":{"turn":2,"step":1,"chunk":{"type":"block-start","index":0,"blockType":"tool-call"}}}
-{"type":"assistant/chunk","seq":33,"time":1785536135065,"data":{"turn":2,"step":1,"chunk":{"type":"tool-call-delta","index":0,"id":"call_list","name":"list_agents","argumentsDelta":"{\"scope\":\"descendants\"}"}}}
-{"type":"assistant/chunk","seq":34,"time":1785730454867,"data":{"turn":2,"step":1,"chunk":{"type":"block-end","index":0,"block":{"type":"tool-call","id":"call_list","name":"list_agents","arguments":"{\"scope\":\"descendants\"}"}}}}
-{"type":"assistant/chunk","seq":35,"time":1785730454867,"data":{"turn":2,"step":1,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
-{"type":"assistant/chunk","seq":36,"time":1785730454867,"data":{"turn":2,"step":1,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
-{"type":"assistant/message","seq":37,"time":1785730454867,"data":{"turn":2,"step":1,"message":{"role":"assistant","content":[{"type":"tool-call","id":"call_list","name":"list_agents","arguments":"{\"scope\":\"descendants\"}"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"199c7794-d782-4957-b7ed-69d094b9c0ef"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[32,33,34,35,36],"surfaceOp":"append"}
-{"type":"tool/call","seq":38,"time":1785730454867,"data":{"turn":2,"step":1,"callId":"call_list","name":"list_agents","arguments":"{\"scope\":\"descendants\"}"}}
-{"type":"tool/result","seq":39,"time":1785730454893,"data":{"turn":2,"step":1,"message":{"source":{"kind":"tool","callId":"call_list"},"content":[{"type":"tool-result","toolCallId":"call_list","content":[{"type":"text","text":"33333333-3333-4333-8333-333333333333 [complete] parent=11111111-1111-4111-8111-111111111111 depth=1 — Reply with CHILD_OK"}],"isError":false}],"role":"user","id":"61ceb650-3e32-413e-9d7e-b6ec8a351858"}},"sourceEventSeqs":[38],"surfaceOp":"append"}
-{"type":"step/end","seq":40,"time":1785730454893,"data":{"turn":2,"step":1}}
-{"type":"step/start","seq":41,"time":1785730454903,"data":{"turn":2,"step":2}}
-{"type":"assistant/chunk","seq":42,"time":1785531795715,"data":{"turn":2,"step":2,"chunk":{"type":"block-start","index":0,"blockType":"tool-call"}}}
-{"type":"assistant/chunk","seq":43,"time":1785536135106,"data":{"turn":2,"step":2,"chunk":{"type":"tool-call-delta","index":0,"id":"call_interrupt","name":"interrupt_agent","argumentsDelta":"{\"agent_id\":\"33333333-3333-4333-8333-333333333333\"}"}}}
-{"type":"assistant/chunk","seq":44,"time":1785730454907,"data":{"turn":2,"step":2,"chunk":{"type":"block-end","index":0,"block":{"type":"tool-call","id":"call_interrupt","name":"interrupt_agent","arguments":"{\"agent_id\":\"33333333-3333-4333-8333-333333333333\"}"}}}}
-{"type":"assistant/chunk","seq":45,"time":1785730454907,"data":{"turn":2,"step":2,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
-{"type":"assistant/chunk","seq":46,"time":1785730454907,"data":{"turn":2,"step":2,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
-{"type":"assistant/message","seq":47,"time":1785730454907,"data":{"turn":2,"step":2,"message":{"role":"assistant","content":[{"type":"tool-call","id":"call_interrupt","name":"interrupt_agent","arguments":"{\"agent_id\":\"33333333-3333-4333-8333-333333333333\"}"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"17c1a7c5-84f5-493e-adb5-6a65219e6ad6"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[42,43,44,45,46],"surfaceOp":"append"}
-{"type":"tool/call","seq":48,"time":1785730454907,"data":{"turn":2,"step":2,"callId":"call_interrupt","name":"interrupt_agent","arguments":"{\"agent_id\":\"33333333-3333-4333-8333-333333333333\"}"}}
-{"type":"tool/result","seq":49,"time":1785730454917,"data":{"turn":2,"step":2,"message":{"source":{"kind":"tool","callId":"call_interrupt"},"content":[{"type":"tool-result","toolCallId":"call_interrupt","content":[{"type":"text","text":"interrupt requested for agent 33333333-3333-4333-8333-333333333333"}],"isError":false}],"role":"user","id":"bf93cbe0-1946-4aef-a4ce-431790026c6f"}},"sourceEventSeqs":[48],"surfaceOp":"append"}
-{"type":"step/end","seq":50,"time":1785730454917,"data":{"turn":2,"step":2}}
-{"type":"step/start","seq":51,"time":1785730454927,"data":{"turn":2,"step":3}}
-{"type":"assistant/chunk","seq":52,"time":1785531795715,"data":{"turn":2,"step":3,"chunk":{"type":"block-start","index":0,"blockType":"text"}}}
-{"type":"assistant/chunk","seq":53,"time":1785536135106,"data":{"turn":2,"step":3,"chunk":{"type":"text-delta","index":0,"text":"DONE"}}}
-{"type":"assistant/chunk","seq":54,"time":1785730454907,"data":{"turn":2,"step":3,"chunk":{"type":"block-end","index":0,"block":{"type":"text","text":"DONE"}}}}
-{"type":"assistant/chunk","seq":55,"time":1785730454907,"data":{"turn":2,"step":3,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":2}}}}
-{"type":"assistant/chunk","seq":56,"time":1785730454907,"data":{"turn":2,"step":3,"chunk":{"type":"finish","reason":{"kind":"stop"}}}}
-{"type":"assistant/message","seq":57,"time":1785730454907,"data":{"turn":2,"step":3,"message":{"role":"assistant","content":[{"type":"text","text":"DONE"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"e4c04cd6-9c23-4c99-a5f7-bac6fc141e95"},"usage":{"inputTokens":10,"outputTokens":2}},"sourceEventSeqs":[52,53,54,55,56],"surfaceOp":"append"}
-{"type":"step/end","seq":58,"time":1785730454938,"data":{"turn":2,"step":3}}
-{"type":"turn/end","seq":59,"time":1785730454938,"data":{"turn":2,"reason":{"kind":"completed"}}}
+{"type":"agent/inbox/spliced","seq":27,"time":1786011499211,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Background subagent 33333333-3333-4333-8333-333333333333 finished and will do no further work unless you send it more."},{"type":"text","text":"Its closing message:"},{"type":"text","text":"CHILD_OK"}],"source":{"kind":"subagent-settled","form":"notice","summary":"Background subagent 33333333-3333-4333-8333-333333333333 finished and will do no further work unless you send it more.","senderSessionId":"33333333-3333-4333-8333-333333333333"},"role":"user","id":"9275a12c-bf9a-48e2-b33b-4fc484e936cb"}]}}
+{"type":"turn/start","seq":28,"time":1786011499211,"data":{"turn":2}}
+{"type":"agent/inbox/spliced","seq":29,"time":1786011499211,"data":{"target":"next-turn","start":0,"removedCount":1,"inserted":[]}}
+{"type":"step/start","seq":30,"time":1786012470343,"data":{"turn":2,"step":1}}
+{"type":"user/message","seq":31,"time":1786012470343,"data":{"content":[{"type":"text","text":"Background subagent 33333333-3333-4333-8333-333333333333 finished and will do no further work unless you send it more."},{"type":"text","text":"Its closing message:"},{"type":"text","text":"CHILD_OK"}],"source":{"kind":"subagent-settled","form":"notice","summary":"Background subagent 33333333-3333-4333-8333-333333333333 finished and will do no further work unless you send it more.","senderSessionId":"33333333-3333-4333-8333-333333333333"},"role":"user","id":"9275a12c-bf9a-48e2-b33b-4fc484e936cb"},"surfaceOp":"append"}
+{"type":"assistant/chunk","seq":32,"time":1786012470346,"data":{"turn":2,"step":1,"chunk":{"type":"block-start","index":0,"blockType":"text"}}}
+{"type":"assistant/chunk","seq":33,"time":1786011499224,"data":{"turn":2,"step":1,"chunk":{"type":"text-delta","index":0,"text":"SUBAGENT_SETTLED_NOTED"}}}
+{"type":"assistant/chunk","seq":34,"time":1786011499224,"data":{"turn":2,"step":1,"chunk":{"type":"block-end","index":0,"block":{"type":"text","text":"SUBAGENT_SETTLED_NOTED"}}}}
+{"type":"assistant/chunk","seq":35,"time":1786011499224,"data":{"turn":2,"step":1,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
+{"type":"assistant/chunk","seq":36,"time":1786011499224,"data":{"turn":2,"step":1,"chunk":{"type":"finish","reason":{"kind":"stop"}}}}
+{"type":"assistant/message","seq":37,"time":1786012470346,"data":{"turn":2,"step":1,"message":{"role":"assistant","content":[{"type":"text","text":"SUBAGENT_SETTLED_NOTED"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"4620e8c0-dd13-4a2f-87dc-f4b66aa51219"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[32,33,34,35,36],"surfaceOp":"append"}
+{"type":"step/end","seq":38,"time":1786012470346,"data":{"turn":2,"step":1}}
+{"type":"turn/end","seq":39,"time":1786012470346,"data":{"turn":2,"reason":{"kind":"completed"}}}
+{"type":"agent/inbox/spliced","seq":40,"time":1786012470360,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Call list_agents once with scope set to descendants and observe the subagent you started. Then call interrupt_agent once with agent_id set to 33333333-3333-4333-8333-333333333333. Then reply with the single word DONE. Do not call any other tool."}],"source":{"kind":"user"},"role":"user","id":"7a2a86d0-80a3-4db5-822f-2d3fcbc16e11"}]}}
+{"type":"turn/start","seq":41,"time":1786011499224,"data":{"turn":3}}
+{"type":"agent/inbox/spliced","seq":42,"time":1786011499224,"data":{"target":"next-turn","start":0,"removedCount":1,"inserted":[]}}
+{"type":"step/start","seq":43,"time":1786011499234,"data":{"turn":3,"step":1}}
+{"type":"user/message","seq":44,"time":1786011499234,"data":{"content":[{"type":"text","text":"Call list_agents once with scope set to descendants and observe the subagent you started. Then call interrupt_agent once with agent_id set to 33333333-3333-4333-8333-333333333333. Then reply with the single word DONE. Do not call any other tool."}],"source":{"kind":"user"},"role":"user","id":"7a2a86d0-80a3-4db5-822f-2d3fcbc16e11"},"surfaceOp":"append"}
+{"type":"assistant/chunk","seq":45,"time":1786011499238,"data":{"turn":3,"step":1,"chunk":{"type":"block-start","index":0,"blockType":"tool-call"}}}
+{"type":"assistant/chunk","seq":46,"time":1786011499238,"data":{"turn":3,"step":1,"chunk":{"type":"tool-call-delta","index":0,"id":"call_list","name":"list_agents","argumentsDelta":"{}"}}}
+{"type":"assistant/chunk","seq":47,"time":1785531795715,"data":{"turn":3,"step":1,"chunk":{"type":"block-end","index":0,"block":{"type":"tool-call","id":"call_list","name":"list_agents","arguments":"{}"}}}}
+{"type":"assistant/chunk","seq":48,"time":1785536135106,"data":{"turn":3,"step":1,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
+{"type":"assistant/chunk","seq":49,"time":1785730454907,"data":{"turn":3,"step":1,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
+{"type":"assistant/message","seq":50,"time":1786011499238,"data":{"turn":3,"step":1,"message":{"role":"assistant","content":[{"type":"tool-call","id":"call_list","name":"list_agents","arguments":"{}"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"d3402e92-2f7e-4cd5-9537-ae9beedeecab"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[45,46,47,48,49],"surfaceOp":"append"}
+{"type":"tool/call","seq":51,"time":1786011499238,"data":{"turn":3,"step":1,"callId":"call_list","name":"list_agents","arguments":"{}"}}
+{"type":"tool/result","seq":52,"time":1786011499267,"data":{"turn":3,"step":1,"message":{"source":{"kind":"tool","callId":"call_list"},"content":[{"type":"tool-result","toolCallId":"call_list","content":[{"type":"text","text":"33333333-3333-4333-8333-333333333333 [ready] — Reply with CHILD_OK"}],"isError":false}],"role":"user","id":"8ae233de-8fde-48d7-a9d0-0d9a480a00d0"}},"sourceEventSeqs":[51],"surfaceOp":"append"}
+{"type":"step/end","seq":53,"time":1785730454908,"data":{"turn":3,"step":1}}
+{"type":"step/start","seq":54,"time":1786011499275,"data":{"turn":3,"step":2}}
+{"type":"assistant/chunk","seq":55,"time":1786011499279,"data":{"turn":3,"step":2,"chunk":{"type":"block-start","index":0,"blockType":"text"}}}
+{"type":"assistant/chunk","seq":56,"time":1786011499279,"data":{"turn":3,"step":2,"chunk":{"type":"text-delta","index":0,"text":"DONE"}}}
+{"type":"assistant/chunk","seq":57,"time":1786011499279,"data":{"turn":3,"step":2,"chunk":{"type":"block-end","index":0,"block":{"type":"text","text":"DONE"}}}}
+{"type":"assistant/chunk","seq":58,"time":1786011499279,"data":{"turn":3,"step":2,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":2}}}}
+{"type":"assistant/chunk","seq":59,"time":1786011499279,"data":{"turn":3,"step":2,"chunk":{"type":"finish","reason":{"kind":"stop"}}}}
+{"type":"assistant/message","seq":60,"time":1786011499279,"data":{"turn":3,"step":2,"message":{"role":"assistant","content":[{"type":"text","text":"DONE"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"3ac0f29f-72ae-44fb-9414-974470095618"},"usage":{"inputTokens":10,"outputTokens":2}},"sourceEventSeqs":[55,56,57,58,59],"surfaceOp":"append"}
+{"type":"step/end","seq":61,"time":1786011499279,"data":{"turn":3,"step":2}}
+{"type":"turn/end","seq":62,"time":1786011499279,"data":{"turn":3,"reason":{"kind":"completed"}}}

examples/acp-agent/tests/snapshots/subagent-list-agents/stdout.expected.jsonl

@@ -2,5 +2,6 @@
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}"}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"STARTED"}}}}
 {"jsonrpc":"2.0","id":3,"result":{"stopReason":"end_turn"}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"SUBAGENT_SETTLED_NOTED"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"DONE"}}}}
 {"jsonrpc":"2.0","id":4,"result":{"stopReason":"end_turn"}}

examples/acp-agent/tests/snapshots/subagent-list-agents/system-prompt.1.expected.md

@@ -0,0 +1,24 @@
+You are an AI agent powered by the DeepSeek Harness SDK.
+
+You are a coding assistant powered by the deepseek-v4-flash model. Your working directory is {{cwd}}. Your bash tool runs under a file sandbox — a `[sandbox: file access denied …]` result is policy, not a command bug.
+
+Verify your work by running the code or tests. Keep answers brief and factual.
+
+
+Use the read tool — not shell commands like cat — to inspect text files. Results include line numbers. Use offset and limit to continue reading large files.
+
+Use the write tool to create files or completely replace file contents. Existing files are overwritten, so read an existing file first (the default fs-policy requires it) and prefer edit for targeted changes.
+
+Use the edit tool for targeted changes to existing UTF-8 text files. It replaces literal old_string with new_string; by default old_string must appear exactly once. If old_string appears multiple times, provide a more specific old_string or set replace_all to true. Read the file first (the default fs-policy requires it), unless you just created or edited it in this session.
+
+Check the [exit code: N] marker on every bash result; investigate failures before moving on.
+
+Track every background task id you start. You are notified in-session when a task finishes — do not busy-poll or sleep on one; keep working on independent steps and do not duplicate a running task's work. Before giving a final answer, collect every still-relevant task with task_output (set wait: true only when you are genuinely blocked on it), and task_kill tasks that stopped mattering.
+
+Use goal tools for one long-running completion objective in the current session. create_goal may infer goal intent from a direct human request in any language; do not create a goal for routine single-turn work. Call get_goal before update_goal and copy its exact goal_id and revision. After session resume or fork, an active goal is disarmed: when a human asks to continue or resume in any wording or language, use update_goal action resume to rearm it. Mark complete only when the objective is actually achieved. Mark blocked only after the same blocking condition persists for at least 3 consecutive goal rounds, and report that concrete condition in blocked_reason; difficulty, uncertainty, or useful remaining work is not blocked.
+
+Use the workflow tool ONLY when the user explicitly asks for a workflow or for large multi-agent orchestration: you write a JavaScript script (the tool description documents the exact format) that fans work out across many subagents with phases and structured results. For one or two delegations, prefer plain subagent calls.
+
+Use the ralph tool ONLY when the direct human explicitly asks for a Ralph loop or fresh-agent iterative execution. Each Ralph round starts a fresh child with no conversation seed and uses the shared workspace as durable memory. Completion and blockers are worker reports, not independent evaluation. Use same-session goal tools for ordinary long-running objectives, and plain subagents or workflows for bounded delegation and fan-out.
+
+Deliver your result with the report tool before you finish: call it once with a self-contained answer. The agent that started you shares your workspace but does not automatically receive your transcript, tool output, or reasoning, so a closing remark such as "done" leaves it nothing it can use. Report earlier as well whenever a partial finding changes what that agent should do next; reporting never ends your turn.

examples/acp-agent/tests/snapshots/subagent-list-agents/tool-schemas.1.expected.json

@@ -133,7 +133,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -194,13 +194,13 @@
     },
     {
       "name": "report",
-      "description": "Report selected content to the agent that started you. Call this zero or more times for progress, findings, or a final answer. Reporting does not end your turn or finish your work, and only your direct parent receives it. A failed call may still have arrived, so do not blindly repeat it.",
+      "description": "Report selected content to the agent that started you. Call this once before you finish, with a self-contained final result, and earlier for progress or findings that change what that agent does next. That agent shares your workspace but does not automatically receive your transcript, tool output, or reasoning, so finishing your work is not itself a result. Reporting does not end your turn or finish your work, and only your direct parent receives it. A failed call may still have arrived, so do not blindly repeat it.",
       "parameters": {
         "type": "object",
         "properties": {
           "output": {
             "type": "string",
-            "description": "Self-contained content for your parent; it does not see your private work."
+            "description": "Actionable content for your parent; summarize conclusions and reference relevant shared paths."
           }
         },
         "required": [
@@ -247,7 +247,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -261,7 +261,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -272,7 +272,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -283,10 +283,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/subagent-mixed/session.1.jsonl

@@ -6,7 +6,7 @@
 {"type":"subagent/descriptor","seq":4,"time":1786357524752,"data":{"version":2,"mode":"one-shot","provider":"spawn","label":"Reply ALPHA only"}}
 {"type":"step/start","seq":5,"time":1786357524755,"data":{"turn":1,"step":1}}
 {"type":"user/message","seq":6,"time":1785730450187,"data":{"content":[{"type":"text","text":"Reply with exactly the word ALPHA and nothing else."}],"source":{"kind":"user"},"role":"user","id":"73ce401a-faaf-408a-879e-7485380d537d"},"surfaceOp":"append"}
-{"type":"user/message","seq":7,"time":1786357524755,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"56ad93fa-0cc0-4ccb-a1b4-258f4801c681"},"surfaceOp":"append"}
+{"type":"user/message","seq":7,"time":1786357524755,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"cb073ca7-b412-4509-99ef-4e1351e7e74d"},"surfaceOp":"append"}
 {"type":"session/title","seq":8,"time":1786357524755,"data":{"title":"Reply with exactly the word","messageSeqs":[6],"source":{"kind":"fallback"}}}
 {"type":"request/header","seq":9,"time":1785730450187,"data":{"header":{"config":{"provider":"deepseek-official","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"initial"}}
 {"type":"request/context","seq":10,"time":1785730450188,"data":{"provider":"deepseek-official","model":"deepseek-v4-flash"}}

examples/acp-agent/tests/snapshots/subagent-mixed/session.2.jsonl

@@ -27,7 +27,7 @@
 {"type":"subagent/descriptor","seq":41,"time":1786357524800,"data":{"version":2,"mode":"one-shot","provider":"fork","label":"Recall project codeword"}}
 {"type":"step/start","seq":42,"time":1786357524803,"data":{"turn":2,"step":1}}
 {"type":"user/message","seq":43,"time":1786357524803,"data":{"content":[{"type":"text","text":"What is the project codeword mentioned earlier in this conversation? Reply with exactly that one word and nothing else."}],"source":{"kind":"user"},"role":"user","id":"86e9f144-764f-460d-b72b-262cffe43d77"},"surfaceOp":"append"}
-{"type":"user/message","seq":44,"time":1786358036899,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"6ea5a774-b0da-47ff-84b7-226a4a207bbf"},"surfaceOp":"append"}
+{"type":"user/message","seq":44,"time":1786358036899,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"d5ebfdfe-de5f-4f3d-9772-7d6179fe8c3d"},"surfaceOp":"append"}
 {"type":"request/header","seq":45,"time":1786358036900,"data":{"header":{"config":{"provider":"deepseek-official","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"resume"}}
 {"type":"assistant/chunk","seq":46,"time":1783352148077,"data":{"turn":2,"step":1,"chunk":{"type":"block-start","index":0,"blockType":"reasoning"}}}
 {"type":"reasoning-chunks","seq0":47,"time0":1783352148077,"data":{"turn":2,"step":1,"index":0,"dt":[0,0,29,0,0,0,35,0,0,0,0,26,29,31,0,30,0,0,27,1,27,0,1,0,0,31,1,0,0,1790157964],"texts":["The"," user"," is"," asking"," me"," to"," recall"," the"," project"," cod","ew","ord"," that"," was"," mentioned"," earlier"," in"," the"," conversation","."," I"," was"," told"," to"," remember"," it",":"," SA","FF","RON","."]}}

examples/acp-agent/tests/snapshots/subagent-multi/session.1.jsonl

@@ -6,7 +6,7 @@
 {"type":"subagent/descriptor","seq":4,"time":1786357521754,"data":{"version":2,"mode":"one-shot","provider":"spawn","label":"Return ALPHA only"}}
 {"type":"step/start","seq":5,"time":1786357521756,"data":{"turn":1,"step":1}}
 {"type":"user/message","seq":6,"time":1785730447828,"data":{"content":[{"type":"text","text":"Reply with exactly the word ALPHA and nothing else."}],"source":{"kind":"user"},"role":"user","id":"a287f842-f6f2-4a17-ab4c-820e41f498d5"},"surfaceOp":"append"}
-{"type":"user/message","seq":7,"time":1786357521756,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"f654b5a4-b4c0-4443-8eab-d84624d804f1"},"surfaceOp":"append"}
+{"type":"user/message","seq":7,"time":1786357521756,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"6f423049-484c-48d6-9cdd-db504d79f892"},"surfaceOp":"append"}
 {"type":"session/title","seq":8,"time":1786357521756,"data":{"title":"Reply with exactly the word","messageSeqs":[6],"source":{"kind":"fallback"}}}
 {"type":"request/header","seq":9,"time":1785730447828,"data":{"header":{"config":{"provider":"deepseek-official","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"initial"}}
 {"type":"request/context","seq":10,"time":1785730447828,"data":{"provider":"deepseek-official","model":"deepseek-v4-flash"}}

examples/acp-agent/tests/snapshots/subagent-multi/session.2.jsonl

@@ -6,7 +6,7 @@
 {"type":"subagent/descriptor","seq":4,"time":1786357521799,"data":{"version":2,"mode":"one-shot","provider":"spawn","label":"Return BETA only"}}
 {"type":"step/start","seq":5,"time":1786357521801,"data":{"turn":1,"step":1}}
 {"type":"user/message","seq":6,"time":1785730447881,"data":{"content":[{"type":"text","text":"Reply with exactly the word BETA and nothing else."}],"source":{"kind":"user"},"role":"user","id":"53f6419d-8ddc-4eee-8803-5b68411336f9"},"surfaceOp":"append"}
-{"type":"user/message","seq":7,"time":1786357521802,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"05843da4-4a5f-46fc-a00f-5257b2bd271d"},"surfaceOp":"append"}
+{"type":"user/message","seq":7,"time":1786357521802,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"5832009f-12a3-4f6e-85e5-257c06f4c716"},"surfaceOp":"append"}
 {"type":"session/title","seq":8,"time":1786357521802,"data":{"title":"Reply with exactly the word","messageSeqs":[6],"source":{"kind":"fallback"}}}
 {"type":"request/header","seq":9,"time":1785730447881,"data":{"header":{"config":{"provider":"deepseek-official","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"initial"}}
 {"type":"request/context","seq":10,"time":1785730447881,"data":{"provider":"deepseek-official","model":"deepseek-v4-flash"}}

examples/acp-agent/tests/snapshots/subagent-parallel/session.1.jsonl

@@ -1,18 +1,18 @@
 {"type":"session","version":0,"id":"bbbbbbbb-0000-4000-8000-000000000002","createdAt":1783352127000,"cwd":"{{cwd}}","parentSession":"aaaaaaaa-0000-4000-8000-000000000001","origin":"subagent","delegationDepth":1}
 {"type":"approval/policy","seq":0,"time":1786373947132,"data":{"policy":"never","source":"delegation"}}
-{"type":"agent/inbox/spliced","seq":1,"time":1786373947134,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Reply with exactly the word ALPHA and nothing else."}],"source":{"kind":"user"},"role":"user","id":"f5d60a48-78a3-4d75-91d7-478017516c5c"}]}}
+{"type":"agent/inbox/spliced","seq":1,"time":1786373947134,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Reply with exactly the word ALPHA and nothing else."}],"source":{"kind":"user"},"role":"user","id":"84b2bc8e-878b-4337-ae82-26c3074069f2"}]}}
 {"type":"turn/start","seq":2,"time":1786373947134,"data":{"turn":1}}
 {"type":"agent/inbox/spliced","seq":3,"time":1786373947134,"data":{"target":"next-turn","start":0,"removedCount":1,"inserted":[]}}
 {"type":"subagent/descriptor","seq":4,"time":1786373947165,"data":{"version":2,"mode":"one-shot","provider":"spawn","label":"Say the word ALPHA"}}
 {"type":"step/start","seq":5,"time":1786373947168,"data":{"turn":1,"step":1}}
-{"type":"user/message","seq":6,"time":1786338530759,"data":{"content":[{"type":"text","text":"Reply with exactly the word ALPHA and nothing else."}],"source":{"kind":"user"},"role":"user","id":"f5d60a48-78a3-4d75-91d7-478017516c5c"},"surfaceOp":"append"}
-{"type":"user/message","seq":7,"time":1786373947168,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"635fd4be-77c6-4891-90ba-2cafa163e166"},"surfaceOp":"append"}
+{"type":"user/message","seq":6,"time":1786338530759,"data":{"content":[{"type":"text","text":"Reply with exactly the word ALPHA and nothing else."}],"source":{"kind":"user"},"role":"user","id":"84b2bc8e-878b-4337-ae82-26c3074069f2"},"surfaceOp":"append"}
+{"type":"user/message","seq":7,"time":1786373947168,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"05fbd821-3adf-4877-b805-2cc5e6de3f9c"},"surfaceOp":"append"}
 {"type":"session/title","seq":8,"time":1786373947168,"data":{"title":"Reply with exactly the word","messageSeqs":[6],"source":{"kind":"fallback"}}}
 {"type":"request/header","seq":9,"time":1786338530759,"data":{"header":{"config":{"provider":"deepseek-official","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"initial"}}
 {"type":"request/context","seq":10,"time":1786338530759,"data":{"provider":"deepseek-official","model":"deepseek-v4-flash"}}
 {"type":"assistant/chunk","seq":11,"time":1786338530769,"data":{"turn":1,"step":1,"chunk":{"type":"block-start","index":0,"blockType":"text"}}}
 {"type":"assistant/chunk","seq":12,"time":1786338530769,"data":{"turn":1,"step":1,"chunk":{"type":"block-end","index":0,"block":{"type":"text","text":"ALPHA"}}}}
 {"type":"assistant/chunk","seq":13,"time":1786338530769,"data":{"turn":1,"step":1,"chunk":{"type":"finish","reason":{"kind":"stop"}}}}
-{"type":"assistant/message","seq":14,"time":1786338530769,"data":{"turn":1,"step":1,"message":{"role":"assistant","content":[{"type":"text","text":"ALPHA"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"4d13c6bf-dc50-4e57-91b0-59561b58986e"}},"sourceEventSeqs":[11,12,13],"surfaceOp":"append"}
+{"type":"assistant/message","seq":14,"time":1786338530769,"data":{"turn":1,"step":1,"message":{"role":"assistant","content":[{"type":"text","text":"ALPHA"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"224c83f1-4449-451d-8f8a-f2889c19068e"}},"sourceEventSeqs":[11,12,13],"surfaceOp":"append"}
 {"type":"step/end","seq":15,"time":1786338530769,"data":{"turn":1,"step":1}}
 {"type":"turn/end","seq":16,"time":1786338530769,"data":{"turn":1,"reason":{"kind":"completed"}}}

examples/acp-agent/tests/snapshots/subagent-parallel/session.2.jsonl

@@ -1,18 +1,18 @@
 {"type":"session","version":0,"id":"cccccccc-0000-4000-8000-000000000003","createdAt":1783352127001,"cwd":"{{cwd}}","parentSession":"aaaaaaaa-0000-4000-8000-000000000001","origin":"subagent","delegationDepth":1}
 {"type":"approval/policy","seq":0,"time":1786373947132,"data":{"policy":"never","source":"delegation"}}
-{"type":"agent/inbox/spliced","seq":1,"time":1786373947133,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Reply with exactly the word ALPHA and nothing else."}],"source":{"kind":"user"},"role":"user","id":"afacd216-5e1b-46e7-afc4-f0eba9da1814"}]}}
+{"type":"agent/inbox/spliced","seq":1,"time":1786373947133,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Reply with exactly the word ALPHA and nothing else."}],"source":{"kind":"user"},"role":"user","id":"a3da85dc-6428-4a31-8653-b7327e518436"}]}}
 {"type":"turn/start","seq":2,"time":1786373947133,"data":{"turn":1}}
 {"type":"agent/inbox/spliced","seq":3,"time":1786373947134,"data":{"target":"next-turn","start":0,"removedCount":1,"inserted":[]}}
 {"type":"subagent/descriptor","seq":4,"time":1786373947170,"data":{"version":2,"mode":"one-shot","provider":"spawn","label":"Say the word ALPHA"}}
 {"type":"step/start","seq":5,"time":1786373947173,"data":{"turn":1,"step":1}}
-{"type":"user/message","seq":6,"time":1786338530749,"data":{"content":[{"type":"text","text":"Reply with exactly the word ALPHA and nothing else."}],"source":{"kind":"user"},"role":"user","id":"afacd216-5e1b-46e7-afc4-f0eba9da1814"},"surfaceOp":"append"}
-{"type":"user/message","seq":7,"time":1786373947174,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"dde02975-239c-422e-9b63-27d98f73346a"},"surfaceOp":"append"}
+{"type":"user/message","seq":6,"time":1786338530749,"data":{"content":[{"type":"text","text":"Reply with exactly the word ALPHA and nothing else."}],"source":{"kind":"user"},"role":"user","id":"a3da85dc-6428-4a31-8653-b7327e518436"},"surfaceOp":"append"}
+{"type":"user/message","seq":7,"time":1786373947174,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"670f5fc4-3eb6-4430-959a-08e8adf25036"},"surfaceOp":"append"}
 {"type":"session/title","seq":8,"time":1786373947174,"data":{"title":"Reply with exactly the word","messageSeqs":[6],"source":{"kind":"fallback"}}}
 {"type":"request/header","seq":9,"time":1786338530749,"data":{"header":{"config":{"provider":"deepseek-official","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"initial"}}
 {"type":"request/context","seq":10,"time":1786338530749,"data":{"provider":"deepseek-official","model":"deepseek-v4-flash"}}
 {"type":"assistant/chunk","seq":11,"time":1786338530759,"data":{"turn":1,"step":1,"chunk":{"type":"block-start","index":0,"blockType":"text"}}}
 {"type":"assistant/chunk","seq":12,"time":1786338530759,"data":{"turn":1,"step":1,"chunk":{"type":"block-end","index":0,"block":{"type":"text","text":"ALPHA"}}}}
 {"type":"assistant/chunk","seq":13,"time":1786338530759,"data":{"turn":1,"step":1,"chunk":{"type":"finish","reason":{"kind":"stop"}}}}
-{"type":"assistant/message","seq":14,"time":1786338530759,"data":{"turn":1,"step":1,"message":{"role":"assistant","content":[{"type":"text","text":"ALPHA"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"11e93a53-9112-4e80-9447-de974373ca94"}},"sourceEventSeqs":[11,12,13],"surfaceOp":"append"}
+{"type":"assistant/message","seq":14,"time":1786338530759,"data":{"turn":1,"step":1,"message":{"role":"assistant","content":[{"type":"text","text":"ALPHA"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"ac2dc91f-7dfa-45f6-88e0-21a2e762c3dd"}},"sourceEventSeqs":[11,12,13],"surfaceOp":"append"}
 {"type":"step/end","seq":15,"time":1786338530760,"data":{"turn":1,"step":1}}
 {"type":"turn/end","seq":16,"time":1786338530760,"data":{"turn":1,"reason":{"kind":"completed"}}}

examples/acp-agent/tests/snapshots/subagent-report/input.json

@@ -14,6 +14,13 @@
     {
       "op": "waitForSubagentTurnEnd"
     },
+    {
+      "op": "waitForTurnStart",
+      "minimumTurn": 2
+    },
+    {
+      "op": "waitForTurnEnd"
+    },
     {
       "op": "promptAndWaitForAgentMessage",
       "text": "Repeat back, verbatim, the exact output the background subagent reported to you. Reply with only that text. Do not use any tools.",

examples/acp-agent/tests/snapshots/subagent-report/session.1.jsonl

@@ -1,14 +1,14 @@
 {"type":"session","version":0,"id":"33333333-3333-4333-8333-333333333333","createdAt":1789000001000,"cwd":"{{cwd}}","parentSession":"11111111-1111-4111-8111-111111111111","origin":"subagent","delegationDepth":1}
 {"type":"subagent/descriptor","seq":0,"time":1785594881508,"data":{"version":2,"mode":"continuable","provider":"spawn","label":"Report a finding","agentProvider":"deepseek-official","agentModel":"deepseek-v4-flash"}}
 {"type":"session/end-seed","seq":1,"time":1785594881508,"data":{}}
-{"type":"approval/policy","seq":2,"time":1786357530605,"data":{"policy":"never","source":"delegation"}}
-{"type":"agent/inbox/spliced","seq":3,"time":1786357530605,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Call the report tool once with output exactly CHILD_REPORT_OK, then stop."}],"source":{"kind":"user"},"role":"user","id":"9045ac78-393a-4f24-b20d-8999286dd6ce"}]}}
-{"type":"turn/start","seq":4,"time":1786357530605,"data":{"turn":1}}
-{"type":"agent/inbox/spliced","seq":5,"time":1786357530605,"data":{"target":"next-turn","start":0,"removedCount":1,"inserted":[]}}
-{"type":"step/start","seq":6,"time":1786357530633,"data":{"turn":1,"step":1}}
+{"type":"approval/policy","seq":2,"time":1786374158805,"data":{"policy":"never","source":"delegation"}}
+{"type":"agent/inbox/spliced","seq":3,"time":1786374158806,"data":{"target":"next-turn","start":0,"inserted":[{"content":[{"type":"text","text":"Call the report tool once with output exactly CHILD_REPORT_OK, then stop."}],"source":{"kind":"user"},"role":"user","id":"9045ac78-393a-4f24-b20d-8999286dd6ce"}]}}
+{"type":"turn/start","seq":4,"time":1786374158806,"data":{"turn":1}}
+{"type":"agent/inbox/spliced","seq":5,"time":1786374158806,"data":{"target":"next-turn","start":0,"removedCount":1,"inserted":[]}}
+{"type":"step/start","seq":6,"time":1786374158840,"data":{"turn":1,"step":1}}
 {"type":"user/message","seq":7,"time":1785730453639,"data":{"content":[{"type":"text","text":"Call the report tool once with output exactly CHILD_REPORT_OK, then stop."}],"source":{"kind":"user"},"role":"user","id":"9045ac78-393a-4f24-b20d-8999286dd6ce"},"surfaceOp":"append"}
-{"type":"user/message","seq":8,"time":1786357530633,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"1677b901-cce7-461a-8b2a-7f119dd9d845"},"surfaceOp":"append"}
-{"type":"session/title","seq":9,"time":1786357530633,"data":{"title":"Call the report tool once","messageSeqs":[7],"source":{"kind":"fallback"}}}
+{"type":"user/message","seq":8,"time":1786374158840,"data":{"content":[{"type":"text","text":"Current runtime context. This snapshot supersedes earlier runtime-context snapshots.\n\nCurrent DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations.\n\nApproval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`).\n\nYou are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}],"source":{"kind":"plugin","plugin":"@deepseek-ai/dsh-system-prompt","form":"snapshot","sections":[{"name":"sandbox:policy","text":"Current DSH file policy: danger-full-access. The DSH file sandbox does not restrict file modifications by available operations."},{"name":"approval:policy","text":"Approval prompts are disabled in this session: actions that require approval are rejected automatically — do not request sandbox escalation (do not set `sandbox_permissions`)."},{"name":"subagent:delegation","text":"You are a delegated subagent: your permission scope was fixed when you were started and cannot be widened from inside this session — operations that require approval are rejected automatically. When the task needs access beyond that scope, do not retry the denied operation; state the limitation in your reply so the delegating agent can handle it."}]},"role":"user","id":"0f107d71-9b56-4ad8-b6f1-d93cb4c82105"},"surfaceOp":"append"}
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@@ -18,7 +18,7 @@
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examples/acp-agent/tests/snapshots/subagent-report/session.jsonl

@@ -1,10 +1,10 @@
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@@ -13,9 +13,9 @@
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+{"type":"assistant/chunk","seq":50,"time":1786012334087,"data":{"turn":3,"step":1,"chunk":{"type":"block-end","index":0,"block":{"type":"text","text":"CHILD_REPORT_OK"}}}}
+{"type":"assistant/chunk","seq":51,"time":1786012334087,"data":{"turn":3,"step":1,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
+{"type":"assistant/chunk","seq":52,"time":1786012334087,"data":{"turn":3,"step":1,"chunk":{"type":"finish","reason":{"kind":"stop"}}}}
+{"type":"assistant/message","seq":53,"time":1786012334087,"data":{"turn":3,"step":1,"message":{"role":"assistant","content":[{"type":"text","text":"CHILD_REPORT_OK"}],"source":{"kind":"model","provider":"deepseek-official","model":"deepseek-v4-flash"},"id":"98d44266-6695-482b-910c-0e1e570fe7a6"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[48,49,50,51,52],"surfaceOp":"append"}
+{"type":"step/end","seq":54,"time":1786012334087,"data":{"turn":3,"step":1}}
+{"type":"turn/end","seq":55,"time":1786012334087,"data":{"turn":3,"reason":{"kind":"completed"}}}

examples/acp-agent/tests/snapshots/subagent-report/stdout.expected.jsonl

@@ -2,5 +2,6 @@
 {"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}"}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"STARTED"}}}}
 {"jsonrpc":"2.0","id":3,"result":{"stopReason":"end_turn"}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"SUBAGENT_SETTLED_NOTED"}}}}
 {"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"CHILD_REPORT_OK"}}}}
 {"jsonrpc":"2.0","id":4,"result":{"stopReason":"end_turn"}}

examples/acp-agent/tests/snapshots/subagent-report/system-prompt.1.expected.md

@@ -0,0 +1,24 @@
+You are an AI agent powered by the DeepSeek Harness SDK.
+
+You are a coding assistant powered by the deepseek-v4-flash model. Your working directory is {{cwd}}. Your bash tool runs under a file sandbox — a `[sandbox: file access denied …]` result is policy, not a command bug.
+
+Verify your work by running the code or tests. Keep answers brief and factual.
+
+
+Use the read tool — not shell commands like cat — to inspect text files. Results include line numbers. Use offset and limit to continue reading large files.
+
+Use the write tool to create files or completely replace file contents. Existing files are overwritten, so read an existing file first (the default fs-policy requires it) and prefer edit for targeted changes.
+
+Use the edit tool for targeted changes to existing UTF-8 text files. It replaces literal old_string with new_string; by default old_string must appear exactly once. If old_string appears multiple times, provide a more specific old_string or set replace_all to true. Read the file first (the default fs-policy requires it), unless you just created or edited it in this session.
+
+Check the [exit code: N] marker on every bash result; investigate failures before moving on.
+
+Track every background task id you start. You are notified in-session when a task finishes — do not busy-poll or sleep on one; keep working on independent steps and do not duplicate a running task's work. Before giving a final answer, collect every still-relevant task with task_output (set wait: true only when you are genuinely blocked on it), and task_kill tasks that stopped mattering.
+
+Use goal tools for one long-running completion objective in the current session. create_goal may infer goal intent from a direct human request in any language; do not create a goal for routine single-turn work. Call get_goal before update_goal and copy its exact goal_id and revision. After session resume or fork, an active goal is disarmed: when a human asks to continue or resume in any wording or language, use update_goal action resume to rearm it. Mark complete only when the objective is actually achieved. Mark blocked only after the same blocking condition persists for at least 3 consecutive goal rounds, and report that concrete condition in blocked_reason; difficulty, uncertainty, or useful remaining work is not blocked.
+
+Use the workflow tool ONLY when the user explicitly asks for a workflow or for large multi-agent orchestration: you write a JavaScript script (the tool description documents the exact format) that fans work out across many subagents with phases and structured results. For one or two delegations, prefer plain subagent calls.
+
+Use the ralph tool ONLY when the direct human explicitly asks for a Ralph loop or fresh-agent iterative execution. Each Ralph round starts a fresh child with no conversation seed and uses the shared workspace as durable memory. Completion and blockers are worker reports, not independent evaluation. Use same-session goal tools for ordinary long-running objectives, and plain subagents or workflows for bounded delegation and fan-out.
+
+Deliver your result with the report tool before you finish: call it once with a self-contained answer. The agent that started you shares your workspace but does not automatically receive your transcript, tool output, or reasoning, so a closing remark such as "done" leaves it nothing it can use. Report earlier as well whenever a partial finding changes what that agent should do next; reporting never ends your turn.

examples/acp-agent/tests/snapshots/subagent-report/tool-schemas.1.expected.json

@@ -133,7 +133,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -194,13 +194,13 @@
     },
     {
       "name": "report",
-      "description": "Report selected content to the agent that started you. Call this zero or more times for progress, findings, or a final answer. Reporting does not end your turn or finish your work, and only your direct parent receives it. A failed call may still have arrived, so do not blindly repeat it.",
+      "description": "Report selected content to the agent that started you. Call this once before you finish, with a self-contained final result, and earlier for progress or findings that change what that agent does next. That agent shares your workspace but does not automatically receive your transcript, tool output, or reasoning, so finishing your work is not itself a result. Reporting does not end your turn or finish your work, and only your direct parent receives it. A failed call may still have arrived, so do not blindly repeat it.",
       "parameters": {
         "type": "object",
         "properties": {
           "output": {
             "type": "string",
-            "description": "Self-contained content for your parent; it does not see your private work."
+            "description": "Actionable content for your parent; summarize conclusions and reference relevant shared paths."
           }
         },
         "required": [
@@ -247,7 +247,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -261,7 +261,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -272,7 +272,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -283,10 +283,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/text-turn/tool-schemas.expected.json

@@ -133,7 +133,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -231,7 +231,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -245,7 +245,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -256,7 +256,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -267,10 +267,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [

examples/acp-agent/tests/snapshots/web-fetch/tool-schemas.expected.json

@@ -133,7 +133,7 @@
     },
     {
       "name": "list_agents",
-      "description": "List your continuable background subagents by durable id and label. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and complete means it exists only in storage — a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
+      "description": "List your continuable background subagents by durable id and label. Use it to recall which ones you started, not to poll for completion — you are told when one finishes. Status comes from the live registry: running means the agent is working right now, idle means it is loaded but between turns (it may be waiting on agents it started), and ready means it exists only in storage — resumable, not terminal, and not a result waiting to be collected; a `send_message` starts a new turn on the same conversation, and a direct child remains a `send_message` candidate in every status. The snapshot is not a delivery promise — `send_message` performs the authoritative check and may still fail. Children that could not be read are reported as diagnostics instead of being silently dropped. Scope `descendants` walks the whole tree below you in stable pre-order, annotating each entry with its durable direct-parent session id and depth. You may use `send_message` only for depth-1 entries; deeper entries are candidates for `interrupt_agent` only.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -231,7 +231,7 @@
     },
     {
       "name": "subagent",
-      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a self-contained task to a subagent (a separate agent that works in its own context) and return its final result. Use this to offload focused, independent work — research, a scoped implementation, an analysis — so it does not consume this conversation's context. The subagent runs to completion and you receive only its final answer, not its intermediate steps. Give it a complete, standalone prompt: it does not see this conversation. Set `run_in_background: true` to start a background subagent that keeps its conversation: this call returns only its subagent id, and the subagent works on its own from there. You are told when it finishes, so never poll or wait on it; `send_message` sends it more work.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -245,7 +245,7 @@
           },
           "run_in_background": {
             "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
+            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call does not wait for it; you are told when it finishes. Send it more work with send_message."
           }
         },
         "required": [
@@ -256,7 +256,7 @@
     },
     {
       "name": "subagent_fork",
-      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps. Set `run_in_background: true` to start a background subagent that keeps its conversation: you receive only its subagent id, never its result, and it works on its own. Use this for work whose result you do not need returned by this call; `send_message` sends it more work.",
+      "description": "Delegate a task to a subagent that inherits this conversation: a child agent seeded with all completed turns so far (it does not see the current in-flight turn), returning only its final result. Use this when the subtask builds on this conversation's context — a follow-up analysis, a review, a continuation — without consuming this conversation's context for the work itself. You receive only its final answer, not its intermediate steps.",
       "parameters": {
         "type": "object",
         "properties": {
@@ -267,10 +267,6 @@
           "prompt": {
             "type": "string",
             "description": "The task for the subagent. It already sees this conversation's completed turns, so build on them freely and state only what is new."
-          },
-          "run_in_background": {
-            "type": "boolean",
-            "description": "Run as a background subagent that keeps its conversation and return only its subagent id. This call never returns its result; send it more work with send_message."
           }
         },
         "required": [