Merge branch 'master' into codex/jsonl-zstd-persistence

2026-07-20 19:58:41 +08:00
parent 82ce9dfe0e 3864b17aaa
commit 153e4b47bd
138 changed files with 644 additions and 225 deletions
@@ -49,9 +49,11 @@ The global registry remains live. A deny-only filter admits a later global name

 The depth limit bounds recursive delegation independently of tool visibility. A top-level agent has depth zero; an in-process child has its parent's validated depth plus one. `maxDepth` is an absolute non-negative safe integer, and a start rejects before child ownership begins when the derived child depth is greater than the cap.

-Every public entry validates the domain rather than relying on one model-facing configuration path. Negative values, fractions, negative zero, non-finite values, unsafe integers, malformed stored parent depth, and derived overflow all reject. Omitting the cap leaves depth unbounded by this mechanism.
+The effective parent depth is the greater of durable `SessionHeader.delegationDepth` and runtime `AgentOptions.subagentDepth`. An in-process child records its derived depth in the session header, and resume restores that header, so a restart cannot lower the recursion count.

-A deployment can combine depth and filtering. For example, it may keep the delegation tool visible at depth one but set `maxDepth: 1`, or deny the delegation tool entirely in children. Neither choice changes the provider's conversation-history behavior.
+Every public entry validates the domain rather than relying on one model-facing configuration path. Negative values, fractions, negative zero, non-finite values, unsafe integers, malformed stored parent depth, and derived overflow all reject. A direct `SubagentStartRequest` may omit the cap to leave depth unbounded; loader-resolved `dsh-tool-subagent` configuration instead defaults to `3`, accepts a numeric override, and uses explicit `'provider-managed'` to omit the cap for an out-of-process provider whose deployment owns its recursion budget. Three is a small finite default that still permits a root plus three descendant generations: the [SDK helper's generated subagent entries](../../../../packages/sdk/helper/src/features/builtin/index.ts) and [JSON-RPC example](../../../../examples/jsonrpc-agent/cordis.yml) use that general policy, while the shipped interactive ACP, headless, and REPL examples pin one. A numeric tool cap fails at provider mount when the provider lacks `depthLimit`.
+
+A deployment can combine depth and filtering, but the numeric cap does not synthesize a filter. The delegation tool stays visible at the cap because authorization may depend on runtime state; every attempted start checks the calling agent's current durable and runtime depth, and a rejected start returns an errored tool result without publishing a child. A deployment may separately deny delegation tools in children when its visibility policy is static. Neither choice changes the provider's conversation-history behavior.

 ### Capability gating keeps providers honest

@@ -83,10 +85,10 @@ A security design would need a separate authority representation, propagation ru

 **Hide only tool schemas.** Presentation-only filtering lets the model execute a tool that the prompt says does not exist through Code Mode or a forged call. One resolver governs both presentation and execution instead.

-**Use only tool filtering to stop recursion.** Removing the delegation tool is useful but provider-specific and does not protect direct service callers or alternate delegation tools. Absolute depth is an independent structural bound.
+**Encode the depth cap as an automatic tool filter.** A creation-time filter snapshots a decision that may depend on runtime state, affects only one configured tool name, and does not protect direct service callers or alternate delegation tools. The provider instead enforces the absolute cap at every start.

 ## Consequences

 Contributors can configure child role, visible global tools, and recursion without defining new providers. Capability checks fail before ownership starts, unpublished setup makes the first request consistent, and one tool resolver prevents presentation/execution drift.

-The cost is that deployments must understand live allow/deny behavior and the distinction between visibility and authority. Provider authors must advertise each supported control accurately, and in-process providers must install every requested contribution before publication. The controls deliberately do not solve security confinement or parent-to-child non-escalation.
+The cost is that deployments must understand live allow/deny behavior and the distinction between visibility and authority. A model may call a visible delegation tool after the current depth policy forbids another child and receive an error. Provider authors must advertise each supported control accurately, and in-process providers must install every requested contribution before publication. The controls deliberately do not solve security confinement or parent-to-child non-escalation.
@@ -59,7 +59,7 @@ The shipped loop drains prompt-to-checkpoint work through plugin-visible service

 A **session** is an append-only log. Each ordinary **turn** claims one queued `send()` item; injection claims none. A claimed `send()` successor awaits the preceding claimed ordinary turn's checkpoint but may share its `running` interval ([decision](../.agents/notes/implemented/simplification/2026-07-17-one-send-one-turn.md)). A turn ends when model and plugins stop it. A **step** is one model request plus tools. Below ([sequence companion](agent-lifecycle.md)), quotes mark durable events; other names are extension points.

-Startup resolves identity. No id mints `<config-id>-session-<uuid>`; `sessionId` resumes or creates; `resumeSessionId` requires history. Active failures emit `agent-loop/config-start-failed(sessionId, error)`, so front doors reject work; teardown stays silent.
+No id mints `<config-id>-session-<uuid>`; `sessionId` resumes/creates; `resumeSessionId` needs history. Resume restores lineage, seeds, and delegation depth pre-publication. Failures emit `agent-loop/config-start-failed(sessionId, error)`; front doors reject; teardown stays silent.

 ### Turn Flow

@@ -1198,8 +1198,7 @@ export interface Config {
  /**
   * Tool filter applied to every child. Filtered tools disappear from its
   * prompt and reject execution. Requires the provider's `toolFilter`
-   * capability; unknown names fail startup. Children otherwise see this tool,
-   * so deny it or set `maxDepth` to bound recursion.
+   * capability; unknown names fail startup.
   */
  toolFilter?: {
    /** Global tool names the child keeps; everything else is removed. */
@@ -1208,10 +1207,15 @@ export interface Config {
    deny?: string[]
  }
  /**
-   * Maximum child depth. Requires the provider's `depthLimit` capability and a
-   * non-negative safe integer. Omission is unbounded.
+   * Maximum child depth: a non-negative safe integer (default `3`; `0` forbids
+   * delegation entirely), or `'provider-managed'` to send no cap. A numeric cap
+   * requires the provider's `depthLimit` capability (mount fails loud
+   * otherwise). The provider checks the calling agent's current depth at every
+   * start; the tool remains model-visible so runtime policy owns rejection.
+   * `'provider-managed'` is for an out-of-process provider (ACP) whose
+   * recursion budget belongs to the child harness's own deployment.
   */
-  maxDepth?: number
+  maxDepth?: number | 'provider-managed'
 }
 ```

@@ -585,7 +585,7 @@ A ready child settled. Scope-filtered dispatch uses the same delegating parent c

 Types: [Scoped](../core-data-structures/scope.md) · [SubagentService](../core-data-structures/subagent.md)

-Source: [`packages/subagent/subagent/src/index.ts:112`](../../packages/subagent/subagent/src/index.ts)
+Source: [`packages/subagent/subagent/src/index.ts:139`](../../packages/subagent/subagent/src/index.ts)

 ### `subagent/provider-added` — emit

@@ -602,7 +602,7 @@ A provider became resolvable in the registry.

 Types: [SubagentProvider](../core-data-structures/subagent.md)

-Source: [`packages/subagent/subagent/src/index.ts:86`](../../packages/subagent/subagent/src/index.ts)
+Source: [`packages/subagent/subagent/src/index.ts:113`](../../packages/subagent/subagent/src/index.ts)

 ### `subagent/provider-removed` — emit

@@ -617,7 +617,7 @@ A provider left the registry. Accepted runs remain holder-owned.
 'subagent/provider-removed'(name: string): void
 ```

-Source: [`packages/subagent/subagent/src/index.ts:92`](../../packages/subagent/subagent/src/index.ts)
+Source: [`packages/subagent/subagent/src/index.ts:119`](../../packages/subagent/subagent/src/index.ts)

 ### `subagent/start` — emit

@@ -639,7 +639,7 @@ A provider established a ready child. For in-process providers, `ctx.agents.get(

 Types: [Scoped](../core-data-structures/scope.md) · [SubagentService](../core-data-structures/subagent.md)

-Source: [`packages/subagent/subagent/src/index.ts:103`](../../packages/subagent/subagent/src/index.ts)
+Source: [`packages/subagent/subagent/src/index.ts:130`](../../packages/subagent/subagent/src/index.ts)

 ## `system-prompt/*`

@@ -216,7 +216,7 @@ roots(): Agent[]

 Types: [Agent](../core-data-structures/core.md) · [SessionId](../core-data-structures/core.md)

-Source: [`packages/core/agent/src/index.ts:217`](../../packages/core/agent/src/index.ts)
+Source: [`packages/core/agent/src/index.ts:223`](../../packages/core/agent/src/index.ts)

 ## `ctx.approval` — `ApprovalService`

@@ -718,9 +718,9 @@ Persistence is intentionally not implemented here — persistence plugins subscr
 * Create a session owned by the calling fiber: disposing that fiber stops
 * event notification and removes the session from the store. `options.seed`
 * populates the session with a copy of those events (replay/fork);
- * `options.meta` attaches creation metadata (validated absolute `cwd`,
- * `parentSession` lineage) as the immutable {@link SessionHeader} (the store
- * fills `version`/`id`/`createdAt`).
+ * `options.meta` attaches creation metadata (validated absolute `cwd`, seed
+ * and parent lineage, and delegation depth) as the immutable
+ * {@link SessionHeader} (the store fills `version`/`id`/`createdAt`).
 *
 * For an agent whose session must be torn down IN ORDER with its loop (so the
 * loop's final flush is captured before the store attachment ends), do NOT use this
@@ -832,7 +832,7 @@ fork(source: SessionForkSource, boundary?: number, childSessionId?: SessionId):

 Types: [CreateSessionOptions](../core-data-structures/persistence.md) · [Session](../core-data-structures/session.md) · [SessionId](../core-data-structures/core.md)

-Source: [`packages/core/session/src/index.ts:549`](../../packages/core/session/src/index.ts)
+Source: [`packages/core/session/src/index.ts:553`](../../packages/core/session/src/index.ts)

 ## `ctx.skills` — `SkillService`

@@ -946,7 +946,7 @@ async start(name: string, request: SubagentStartRequest): Promise<SubagentRun>

 Types: [SubagentProvider](../core-data-structures/subagent.md) · [SubagentRun](../core-data-structures/subagent.md) · [SubagentStartRequest](../core-data-structures/subagent.md)

-Source: [`packages/subagent/subagent/src/index.ts:153`](../../packages/subagent/subagent/src/index.ts)
+Source: [`packages/subagent/subagent/src/index.ts:180`](../../packages/subagent/subagent/src/index.ts)

 ## `ctx.systemPrompt` — `SystemPrompt`

@@ -60,12 +60,18 @@ interface SessionHeader {
   * boundary lets resume and replay distinguish parent history from child work.
   */
  readonly seedLength?: number
+  /**
+   * Delegation depth: absent (zero) for a top-level session, parent depth + 1
+   * for a subagent child. Persisted so a recursion budget survives restart and
+   * resume — a runtime-only depth would reset a resumed child to top-level.
+   */
+  readonly delegationDepth?: number
 }
 ```

 ## `CreateSessionOptions` — seeding and metadata

-Creating a `Session` through the store takes a `seed` (replay/fork an existing event log) and `meta` (the storage-level fields the store folds into a `SessionHeader`). The store fills in `version`/`id` and defaults `createdAt`; the caller supplies the validated absolute `cwd`, the `parentSession` lineage, the `seedLength` seed boundary, and — only when reconstructing a persisted session — the original `createdAt` to preserve it.
+Creating a `Session` through the store takes a `seed` (replay/fork an existing event log) and `meta` (the storage-level fields the store folds into a `SessionHeader`). The store fills in `version`/`id` and defaults `createdAt`; the caller supplies the validated absolute `cwd`, the `parentSession` lineage, the `seedLength` seed boundary, the `delegationDepth`, and — only when reconstructing a persisted session — the original `createdAt` to preserve it.

 ```ts type-equiv
 /**
@@ -85,6 +91,7 @@ interface CreateSessionOptions {
    readonly parentSession?: SessionId
    readonly createdAt?: number
    readonly seedLength?: number
+    readonly delegationDepth?: number
  }
 }
 ```
@@ -237,5 +237,5 @@ interface SubagentProvider {

 The spawn and fork backends create an ordinary agent through `parent.ctx`, pass cancellation into core creation, and dispose through `AgentHandle`. Provider removal blocks new starts without revoking accepted runs. Each child gets a new flat scope rather than inheriting parent registrations. Depth and fork seeding reuse existing agent and session vocabulary:

- **Delegation depth** is a merge-extensible `AgentOptions.subagentDepth` field (`0` for a top-level agent, parent + 1 for a child). Only `undefined` means top level; every stored present value must be a non-negative safe integer. The seam owns it — the loop neither sets nor reads it — so a nested spawn validates its parent's stored depth, rejects a derived child depth outside the safe-integer domain, and applies a defined absolute `request.maxDepth` cap to that child.
+- **Delegation depth** is durable `SessionHeader.delegationDepth` plus the merge-extensible runtime field `AgentOptions.subagentDepth`; absence means top-level depth zero, and the greater present value is authoritative. The seam owns both fields — the loop neither sets nor reads them — so an in-process child persists parent depth + 1, resume cannot lower it, and every start rejects a derived depth outside the safe-integer domain or above a defined absolute `request.maxDepth` cap.
 - **Fork seeding** uses `CreateAgentOptions.seed` (a `SessionEvent[]` prefix threaded through `AgentLoop.createAgent` → `ctx.sessions.prepare({ seed })`, the same primitive `resume` uses). The fork backend passes a *balanced completed-turn prefix* of the parent's log — the parent's events up to and including its last `turn/end` — so the seed is contiguous-from-0 and the [invariants](../../packages/support/invariants) replay accepts it (the in-flight, unbalanced turn is excluded).
@@ -32,10 +32,10 @@ This matrix shows which packages dispatch each harness-owned event and which pac
 | `session/disposed` | `emit` | [`packages/core/session/src/index.ts:57`](../packages/core/session/src/index.ts) | [`session`](../packages/core/session) (`events.dispatch`) | [`agent-loop`](../packages/core/agent-loop), [`session-persistence`](../packages/session-persistence/session-persistence) |
 | `session/event` | `emit` | [`packages/core/session/src/index.ts:69`](../packages/core/session/src/index.ts) | [`session`](../packages/core/session) (`events.dispatch`) | [`acp`](../packages/ui/acp), [`cli-demo`](../packages/examples/cli-demo), [`invariants`](../packages/support/invariants), [`jsonrpc`](../packages/ui/jsonrpc), [`session-persistence`](../packages/session-persistence/session-persistence), [`stdio`](../packages/ui/stdio), [`token-meter`](../packages/llm/token-meter), [`tui`](../packages/ui/tui), [`workspace-context`](../packages/context/workspace-context) |
 | `session/flush` | `parallel` | [`packages/core/session/src/index.ts:79`](../packages/core/session/src/index.ts) | [`session`](../packages/core/session) (`events.dispatch`) | [`session-persistence`](../packages/session-persistence/session-persistence) |
-| `subagent/end` | `emit` | [`packages/subagent/subagent/src/index.ts:112`](../packages/subagent/subagent/src/index.ts) | [`subagent`](../packages/subagent/subagent) (`events.dispatch`) | [`hooks-claude`](../packages/hooks/hooks-claude), [`jsonrpc`](../packages/ui/jsonrpc) |
-| `subagent/provider-added` | `emit` | [`packages/subagent/subagent/src/index.ts:86`](../packages/subagent/subagent/src/index.ts) | [`subagent`](../packages/subagent/subagent) (`emit`) | [`tool-subagent`](../packages/subagent/tool-subagent) |
-| `subagent/provider-removed` | `emit` | [`packages/subagent/subagent/src/index.ts:92`](../packages/subagent/subagent/src/index.ts) | [`subagent`](../packages/subagent/subagent) (`events.dispatch`) | [`tool-subagent`](../packages/subagent/tool-subagent) |
-| `subagent/start` | `emit` | [`packages/subagent/subagent/src/index.ts:103`](../packages/subagent/subagent/src/index.ts) | [`subagent`](../packages/subagent/subagent) (`events.dispatch`) | [`hooks-claude`](../packages/hooks/hooks-claude) |
+| `subagent/end` | `emit` | [`packages/subagent/subagent/src/index.ts:139`](../packages/subagent/subagent/src/index.ts) | [`subagent`](../packages/subagent/subagent) (`events.dispatch`) | [`hooks-claude`](../packages/hooks/hooks-claude), [`jsonrpc`](../packages/ui/jsonrpc) |
+| `subagent/provider-added` | `emit` | [`packages/subagent/subagent/src/index.ts:113`](../packages/subagent/subagent/src/index.ts) | [`subagent`](../packages/subagent/subagent) (`emit`) | [`tool-subagent`](../packages/subagent/tool-subagent) |
+| `subagent/provider-removed` | `emit` | [`packages/subagent/subagent/src/index.ts:119`](../packages/subagent/subagent/src/index.ts) | [`subagent`](../packages/subagent/subagent) (`events.dispatch`) | [`tool-subagent`](../packages/subagent/tool-subagent) |
+| `subagent/start` | `emit` | [`packages/subagent/subagent/src/index.ts:130`](../packages/subagent/subagent/src/index.ts) | [`subagent`](../packages/subagent/subagent) (`events.dispatch`) | [`hooks-claude`](../packages/hooks/hooks-claude) |
 | `system-prompt/assemble` | `waterfall` | [`packages/core/system-prompt/src/index.ts:27`](../packages/core/system-prompt/src/index.ts) | [`system-prompt`](../packages/core/system-prompt) (`waterfall`) | [`acp`](../packages/ui/acp) |
 | `system-prompt/change` | `emit` | [`packages/core/system-prompt/src/index.ts:33`](../packages/core/system-prompt/src/index.ts) | [`system-prompt`](../packages/core/system-prompt) (`emit`) | - |
 | `tools/change` | `emit` | [`packages/core/tools/src/index.ts:116`](../packages/core/tools/src/index.ts) | [`tools`](../packages/core/tools) (`emit`) | - |
@@ -14,4 +14,4 @@ FIXME(glossary-completeness): Expand this glossary before the first release so i
 - **shadowing** — most-specific-wins name resolution: a scoped tool/section/variable replaces its same-named global twin for that scope alone. The per-agent persona and per-agent tool-variant mechanism.
 - **restriction / scope-local registration** — a restriction (`tools.restrict`) filters the GLOBAL tool surface for one scope (compose by intersection); scope-local registrations are merged after that filter. A filtered-away global tool is absent from the prompt AND refuses execution, indistinguishably from a nonexistent one.
 - **setup window** — the creation slot where a creator composes an agent's scoped world (`CreateAgentOptions.setup`): after the scope and agent object exist but before the agent or session is published, `agent/session-start` fires, or the first prompt is assembled. Setup registers; it never drives the agent.
- **lineage** — parent/child facts carried as data (`parentSession`, `subagentDepth`); never affects visibility. <a id="lineage"></a>
+- **lineage** — parent/child facts carried as data (`parentSession`, durable `delegationDepth`, runtime `subagentDepth`); never affects visibility. <a id="lineage"></a>
@@ -79,7 +79,7 @@ export type SessionEvent<T extends SessionEventType = SessionEventType> = {
 }[T]
 ```

-Sources: [`packages/core/session/src/types.ts:256`](../packages/core/session/src/types.ts) · [`packages/core/session/src/types.ts:263`](../packages/core/session/src/types.ts) · [`packages/core/session/src/types.ts:293`](../packages/core/session/src/types.ts) · [`packages/core/session/src/types.ts:325`](../packages/core/session/src/types.ts)
+Sources: [`packages/core/session/src/types.ts:263`](../packages/core/session/src/types.ts) · [`packages/core/session/src/types.ts:270`](../packages/core/session/src/types.ts) · [`packages/core/session/src/types.ts:300`](../packages/core/session/src/types.ts) · [`packages/core/session/src/types.ts:332`](../packages/core/session/src/types.ts)

 ## Events

@@ -151,7 +151,7 @@ Source: [`packages/ui/user-approval/src/index.ts:68`](../packages/ui/user-approv

 Types: [StreamChunk](core-data-structures/llm-streaming.md)

-Source: [`packages/core/session/src/types.ts:220`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:227`](../packages/core/session/src/types.ts)

 #### `assistant/message` — surface

@@ -167,7 +167,7 @@ Source: [`packages/core/session/src/types.ts:220`](../packages/core/session/src/

 Types: [ContentBlock](core-data-structures/core.md) · [TokenUsage](core-data-structures/llm-streaming.md)

-Source: [`packages/core/session/src/types.ts:227`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:234`](../packages/core/session/src/types.ts)

 ### `compact/*`

@@ -246,7 +246,7 @@ Source: [`packages/compact/compact/src/types.ts:22`](../packages/compact/compact

 Types: [ContentBlock](core-data-structures/core.md) · [MessageSource](core-data-structures/core.md)

-Source: [`packages/core/session/src/types.ts:214`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:221`](../packages/core/session/src/types.ts)

 ### `hook/*`

@@ -324,7 +324,7 @@ Source: [`packages/ui/permission/src/index.ts:36`](../packages/ui/permission/src

 Types: [ContentBlock](core-data-structures/core.md) · [MessageSource](core-data-structures/core.md)

-Source: [`packages/core/session/src/types.ts:202`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:209`](../packages/core/session/src/types.ts)

 ### `request/*`

@@ -338,7 +338,7 @@ Source: [`packages/core/session/src/types.ts:202`](../packages/core/session/src/
 'request/header': { header: EpochHeader; reason: RequestHeaderReason }
 ```

-Source: [`packages/core/session/src/types.ts:252`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:259`](../packages/core/session/src/types.ts)

 ### `sandbox/*`

@@ -369,7 +369,7 @@ Source: [`packages/sandbox/sandbox-policy/src/session-mode.ts:34`](../packages/s

 Types: [ContentBlock](core-data-structures/core.md) · [MessageSource](core-data-structures/core.md)

-Source: [`packages/core/session/src/types.ts:245`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:252`](../packages/core/session/src/types.ts)

 ### `step/*`

@@ -380,7 +380,7 @@ Source: [`packages/core/session/src/types.ts:245`](../packages/core/session/src/
 'step/end': { turn: number; step: number }
 ```

-Source: [`packages/core/session/src/types.ts:195`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:202`](../packages/core/session/src/types.ts)

 #### `step/start` — log-only

@@ -389,7 +389,7 @@ Source: [`packages/core/session/src/types.ts:195`](../packages/core/session/src/
 'step/start': { turn: number; step: number }
 ```

-Source: [`packages/core/session/src/types.ts:193`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:200`](../packages/core/session/src/types.ts)

 ### `todo/*`

@@ -402,7 +402,7 @@ Source: [`packages/core/session/src/types.ts:193`](../packages/core/session/src/

 Types: [TodoItem](core-data-structures/session.md)

-Source: [`packages/core/session/src/types.ts:247`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:254`](../packages/core/session/src/types.ts)

 ### `tool/*`

@@ -419,7 +419,7 @@ Source: [`packages/core/session/src/types.ts:247`](../packages/core/session/src/

 Types: [CallId](core-data-structures/core.md)

-Source: [`packages/core/session/src/types.ts:233`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:240`](../packages/core/session/src/types.ts)

 #### `tool/code-dispatch` — log-only

@@ -463,7 +463,7 @@ Source: [`packages/core/tools/src/code-mode.ts:34`](../packages/core/tools/src/c

 Types: [CallId](core-data-structures/core.md) · [ContentBlock](core-data-structures/core.md)

-Source: [`packages/core/session/src/types.ts:243`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:250`](../packages/core/session/src/types.ts)

 ### `turn/*`

@@ -481,7 +481,7 @@ Source: [`packages/core/session/src/types.ts:243`](../packages/core/session/src/

 Types: [TurnEndReason](core-data-structures/session.md)

-Source: [`packages/core/session/src/types.ts:191`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:198`](../packages/core/session/src/types.ts)

 #### `turn/start` — log-only

@@ -497,7 +497,7 @@ Source: [`packages/core/session/src/types.ts:191`](../packages/core/session/src/

 Types: [TurnTrigger](core-data-structures/session.md)

-Source: [`packages/core/session/src/types.ts:184`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:191`](../packages/core/session/src/types.ts)

 ### `user/*`

@@ -510,4 +510,4 @@ Source: [`packages/core/session/src/types.ts:184`](../packages/core/session/src/

 Types: [ContentBlock](core-data-structures/core.md) · [MessageSource](core-data-structures/core.md)

-Source: [`packages/core/session/src/types.ts:197`](../packages/core/session/src/types.ts)
+Source: [`packages/core/session/src/types.ts:204`](../packages/core/session/src/types.ts)
@@ -96,12 +96,14 @@
  config:
    provider: spawn
    toolName: subagent
+    maxDepth: 1

 - id: tool-subagent-fork
  name: '@deepseek-ai/dsh-tool-subagent'
  config:
    provider: fork
    toolName: subagent_fork
+    maxDepth: 1


 # The worker-thread workflow engine fans a model-written JavaScript script's
@@ -0,0 +1,36 @@
+# Keyless counterpart to depth-two.cordis.yml: apply the depth patch and replace
+# the live adapter with per-session replay.
+- id: base
+  name: '@cordisjs/plugin-include'
+  config:
+    path: ./cordis.yml
+    patches:
+      - id: llm-deepseek
+        name: '@deepseek-ai/dsh-llm-deepseek'
+        disabled: true
+      - 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
+        name: '@deepseek-ai/dsh-tool-subagent'
+        config:
+          provider: spawn
+          toolName: subagent
+          maxDepth: 2
+      - insert:
+          - id: llm-replay
+            name: '@deepseek-ai/dsh-llm-replay'
+            config:
+              providers:
+                - id: deepseek
+                  name: DeepSeek
+                  models:
+                    - id: deepseek-v4-flash
+                    - id: deepseek-v4-pro
@@ -0,0 +1,13 @@
+# Depth-limit snapshot overlay: keep the default composition and allow two
+# generations of spawn children before runtime enforcement rejects another.
+- id: base
+  name: '@cordisjs/plugin-include'
+  config:
+    path: ./cordis.yml
+    patches:
+      - id: tool-subagent
+        name: '@deepseek-ai/dsh-tool-subagent'
+        config:
+          provider: spawn
+          toolName: subagent
+          maxDepth: 2
@@ -30,6 +30,7 @@ const BOTH_MODE_CONFIG = fileURLToPath(new URL('../both-mode.cordis.yml', import
 const WORKSPACE_CONTEXT_CONFIG = fileURLToPath(new URL('../workspace-context.cordis.yml', import.meta.url))
 const ADVANCED_CONFIG = fileURLToPath(new URL('../advanced.cordis.yml', import.meta.url))
 const FS_CONFIG = fileURLToPath(new URL('../fs.cordis.yml', import.meta.url))
+const DEPTH_TWO_CONFIG = fileURLToPath(new URL('../depth-two.cordis.yml', import.meta.url))

 function snapshotModeFromEnv(value: string | undefined): SnapshotSuiteOptions['mode'] {
  switch (value) {
@@ -109,6 +110,13 @@ const SCENARIOS: Scenario[] = [
  { name: 'subagent-multi', hasModelTurn: true, recorded: true },
  { name: 'subagent-fork', hasModelTurn: true, recorded: true },
  { name: 'subagent-mixed', hasModelTurn: true, recorded: true },
+  {
+    name: 'subagent-depth-two-rejection',
+    hasModelTurn: true,
+    recorded: false,
+    overridden: true,
+    configPath: DEPTH_TWO_CONFIG,
+  },
  // The workflow tool: the model writes a one-child orchestration script; the
  // child runs as a spawn subagent under the worker-thread engine (its session is the
  // child fixture), and the tool result carries the script's return value.
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"ed16a7e7-a76f-459f-b889-d4c424d66ef6","createdAt":1783421406247,"cwd":"/Users/wwl/workspace/deepseek-harness"}
+{"type":"session","version":0,"id":"ed16a7e7-a76f-459f-b889-d4c424d66ef6","createdAt":1783421406247,"cwd":"/Users/wwl/workspace/deepseek-harness","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783421410388,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783421410388,"data":{"content":[{"type":"text","text":"你好"}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783421410389,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"22222222-2222-4222-8222-222222222222","createdAt":1783950001000,"cwd":"/tmp/advanced-acp","parentSession":"11111111-1111-4111-8111-111111111111"}
+{"type":"session","version":0,"id":"22222222-2222-4222-8222-222222222222","createdAt":1783950001000,"cwd":"/tmp/advanced-acp","parentSession":"11111111-1111-4111-8111-111111111111","delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783957884563,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783957884563,"data":{"content":[{"type":"text","text":"Reply with exactly DIRECT_CHILD_OK and nothing else."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783957884564,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"33333333-3333-4333-8333-333333333333","createdAt":1783950002000,"cwd":"/tmp/advanced-acp","parentSession":"11111111-1111-4111-8111-111111111111"}
+{"type":"session","version":0,"id":"33333333-3333-4333-8333-333333333333","createdAt":1783950002000,"cwd":"/tmp/advanced-acp","parentSession":"11111111-1111-4111-8111-111111111111","delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783957884700,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783957884700,"data":{"content":[{"type":"text","text":"Reply with exactly WORKFLOW_CHILD_OK and nothing else."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783957884700,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"11111111-1111-4111-8111-111111111111","createdAt":1783950000000,"cwd":"/tmp/advanced-acp"}
+{"type":"session","version":0,"id":"11111111-1111-4111-8111-111111111111","createdAt":1783950000000,"cwd":"/tmp/advanced-acp","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783957884479,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783957884479,"data":{"content":[{"type":"text","text":"Run this advanced flow exactly once: mount a no-op Cordis plugin named snapshot-marker; use run_code to inspect the live dynamic mounts through tools.cordis_inspect; delegate once to a direct spawn child; run one workflow that delegates to another spawn child; unmount dyn-1; then reply with exactly ADVANCED_ACP_OK."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783957884486,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}"}
+{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":0,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":0,"data":{"content":[{"type":"text","text":"Use the bash tool to print a large deterministic output, then reply DONE."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":0,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"bcd7e943-7b84-4264-82d0-f64e50d0d7ce","createdAt":1783611774317,"cwd":"/var/folders/2c/psb0_fmx7hbgz558xjt_f0l00000gn/T/acp-snap-cwd-52lrTl"}
+{"type":"session","version":0,"id":"bcd7e943-7b84-4264-82d0-f64e50d0d7ce","createdAt":1783611774317,"cwd":"/var/folders/2c/psb0_fmx7hbgz558xjt_f0l00000gn/T/acp-snap-cwd-52lrTl","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783611774323,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783611774323,"data":{"content":[{"type":"text","text":"Call the run_code tool (NOT the native bash tool directly) with a program that runs exactly `echo BOTH_OK` via tools.bash and returns its output. Then reply with that output only and stop."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783611774324,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}"}
+{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1784437195072,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1784437195072,"data":{"content":[{"type":"text","text":"Run two shell commands: wait for cancellation, then write skipped.txt."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1784437195076,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}"}
+{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":0,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":0,"data":{"content":[{"type":"text","text":"Start a long task; this turn will be cancelled mid-stream."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":0,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"94cd1ae4-e1d1-4ec8-9d27-50a1f849b6b3","createdAt":1783611771392,"cwd":"/var/folders/2c/psb0_fmx7hbgz558xjt_f0l00000gn/T/acp-snap-cwd-BteTVR"}
+{"type":"session","version":0,"id":"94cd1ae4-e1d1-4ec8-9d27-50a1f849b6b3","createdAt":1783611771392,"cwd":"/var/folders/2c/psb0_fmx7hbgz558xjt_f0l00000gn/T/acp-snap-cwd-BteTVR","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783611771394,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783611771394,"data":{"content":[{"type":"text","text":"Using ONE run_code program: call the bash tool twice — exactly `echo CODE_ONE` then exactly `echo CODE_TWO` — and return the two outputs joined with a plus sign. Then reply with that joined string only and stop."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783611771396,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"65fbb8a6-624c-4d6a-bf5d-a7a7d14f2b49","createdAt":1783921765266,"cwd":"/var/folders/_g/59jgff8x2gqd39f5vy1wnbfc0000gn/T/acp-snap-cwd-uorU26"}
+{"type":"session","version":0,"id":"65fbb8a6-624c-4d6a-bf5d-a7a7d14f2b49","createdAt":1783921765266,"cwd":"/var/folders/_g/59jgff8x2gqd39f5vy1wnbfc0000gn/T/acp-snap-cwd-uorU26","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783921765269,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783921765269,"data":{"content":[{"type":"text","text":"Using ONE run_code program, call tools.read on nested/task.txt. After the program finishes, answer the workspace handshake question using the newly discovered instructions: What is the Code Mode workspace handshake?"}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783921765275,"data":{"turn":1,"step":1}}
@@ -1 +1 @@
-{"type":"session","version":0,"id":"00000000-0000-0000-0000-000000000000","createdAt":0}
+{"type":"session","version":0,"id":"00000000-0000-0000-0000-000000000000","createdAt":0,"delegationDepth":0}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"22222222-2222-4222-8222-222222222222","createdAt":1783951000000,"cwd":"/tmp/cordis-inspect-jsdoc"}
+{"type":"session","version":0,"id":"22222222-2222-4222-8222-222222222222","createdAt":1783951000000,"cwd":"/tmp/cordis-inspect-jsdoc","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1784449176717,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1784449176718,"data":{"content":[{"type":"text","text":"Inspect the exact tools service API and tools/pre-execute event with cordis_inspect, then reply with exactly CORDIS_INSPECT_JSDOC_OK."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1784449176720,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}"}
+{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":0,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":0,"data":{"content":[{"type":"text","text":"This prompt triggers a recorded provider error."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":0,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"f3cbd087-fb45-4b32-b0f2-3082d65bfcb4","createdAt":1783860675270,"cwd":"/var/folders/2g/b32ct0qn1d728l_v6tdkjytr0000gn/T/acp-snap-cwd-cbBLh2"}
+{"type":"session","version":0,"id":"f3cbd087-fb45-4b32-b0f2-3082d65bfcb4","createdAt":1783860675270,"cwd":"/var/folders/2g/b32ct0qn1d728l_v6tdkjytr0000gn/T/acp-snap-cwd-cbBLh2","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783860675271,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"permission/preset","seq":1,"time":1783962245380,"data":{"preset":"workspace-write"}}
 {"type":"sandbox/mode","seq":2,"time":1784518116517,"data":{"mode":"workspace-write"}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"d692fe7f-7079-4ee4-8b06-f44fd026d4ea","createdAt":1783860679475,"cwd":"/var/folders/2g/b32ct0qn1d728l_v6tdkjytr0000gn/T/acp-snap-cwd-Hn29Od"}
+{"type":"session","version":0,"id":"d692fe7f-7079-4ee4-8b06-f44fd026d4ea","createdAt":1783860679475,"cwd":"/var/folders/2g/b32ct0qn1d728l_v6tdkjytr0000gn/T/acp-snap-cwd-Hn29Od","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783860679476,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"permission/preset","seq":1,"time":1783962246267,"data":{"preset":"workspace-write"}}
 {"type":"sandbox/mode","seq":2,"time":1784518117237,"data":{"mode":"workspace-write"}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"736c4bd8-41bd-43fb-9030-b4df3b2a4f83","createdAt":1783352084735,"cwd":"/tmp/acp-snap-cwd-0BxHdV"}
+{"type":"session","version":0,"id":"736c4bd8-41bd-43fb-9030-b4df3b2a4f83","createdAt":1783352084735,"cwd":"/tmp/acp-snap-cwd-0BxHdV","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352084740,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352084740,"data":{"content":[{"type":"text","text":"First use the read tool to read config.txt in the current directory. Then use the edit tool (NOT bash) to replace the literal text DEBUG with RELEASE in that file. Then reply with exactly the single word DONE."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352084742,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"977a4820-f609-4b48-9039-adcdd921c5fe","createdAt":1784045702340,"cwd":"/var/folders/2g/b32ct0qn1d728l_v6tdkjytr0000gn/T/acp-snap-cwd-vmEGzd"}
+{"type":"session","version":0,"id":"977a4820-f609-4b48-9039-adcdd921c5fe","createdAt":1784045702340,"cwd":"/var/folders/2g/b32ct0qn1d728l_v6tdkjytr0000gn/T/acp-snap-cwd-vmEGzd","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1784045702342,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"permission/preset","seq":1,"time":1784045702343,"data":{"preset":"workspace-write"}}
 {"type":"sandbox/mode","seq":2,"time":1784045702343,"data":{"mode":"workspace-write"}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"b3292503-2c3d-4677-804d-1ed6802a4bc5","createdAt":1783611702544,"cwd":"/var/folders/2c/psb0_fmx7hbgz558xjt_f0l00000gn/T/acp-snap-cwd-QzoqnB"}
+{"type":"session","version":0,"id":"b3292503-2c3d-4677-804d-1ed6802a4bc5","createdAt":1783611702544,"cwd":"/var/folders/2c/psb0_fmx7hbgz558xjt_f0l00000gn/T/acp-snap-cwd-QzoqnB","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783611702550,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783611702550,"data":{"content":[{"type":"text","text":"Do NOT use the read tool and do NOT use bash or shell commands. Immediately use the edit tool to replace the literal text blue with green in settings.txt in the current directory. Do not read the file first. After the tool result, reply with exactly the single word DONE."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783611702550,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"b5639b9d-99a9-49e4-83da-77e6caa702be","createdAt":1783352099834,"cwd":"/tmp/acp-snap-cwd-N9HCkt"}
+{"type":"session","version":0,"id":"b5639b9d-99a9-49e4-83da-77e6caa702be","createdAt":1783352099834,"cwd":"/tmp/acp-snap-cwd-N9HCkt","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352099838,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352099839,"data":{"content":[{"type":"text","text":"Use the read tool (NOT bash) with offset 5 and limit 4 to read lines 5 through 8 of big.txt in the current directory. Then reply with exactly the single word DONE."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352099840,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"a57f852d-d476-4716-a380-8a1116e4d905","createdAt":1783352072464,"cwd":"/tmp/acp-snap-cwd-PEETkS"}
+{"type":"session","version":0,"id":"a57f852d-d476-4716-a380-8a1116e4d905","createdAt":1783352072464,"cwd":"/tmp/acp-snap-cwd-PEETkS","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352072468,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352072469,"data":{"content":[{"type":"text","text":"Use the read tool (NOT bash) to read the file greeting.txt in the current directory, then reply with exactly the single word DONE."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352072470,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"e128dda9-ed11-4868-8266-0ef90d03c3d6","createdAt":1783352050748,"cwd":"/tmp/acp-snap-cwd-mrFUuk"}
+{"type":"session","version":0,"id":"e128dda9-ed11-4868-8266-0ef90d03c3d6","createdAt":1783352050748,"cwd":"/tmp/acp-snap-cwd-mrFUuk","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352050753,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352050753,"data":{"content":[{"type":"text","text":"Use the bash tool to run exactly: echo TERMINAL_OK. Then reply with the single word DONE and stop."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352050755,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"e04cc262-6c89-4586-88d7-3e919240d735","createdAt":1783352092215,"cwd":"/tmp/acp-snap-cwd-hH2sGY"}
+{"type":"session","version":0,"id":"e04cc262-6c89-4586-88d7-3e919240d735","createdAt":1783352092215,"cwd":"/tmp/acp-snap-cwd-hH2sGY","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352092220,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352092221,"data":{"content":[{"type":"text","text":"First use the read tool to read data.txt in the current directory. Then use the write tool (NOT bash) to replace its entire contents with exactly the single line: replaced. Then reply with exactly the single word DONE."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352092223,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"fdcab4d0-e5e4-4a06-9195-be8f7049d67e","createdAt":1783352078749,"cwd":"/tmp/acp-snap-cwd-sNvn5N"}
+{"type":"session","version":0,"id":"fdcab4d0-e5e4-4a06-9195-be8f7049d67e","createdAt":1783352078749,"cwd":"/tmp/acp-snap-cwd-sNvn5N","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352078754,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352078754,"data":{"content":[{"type":"text","text":"Use the write tool (NOT bash) to create a file named notes.txt in the current directory containing exactly the single line: hello world. Then reply with exactly the single word DONE."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352078756,"data":{"turn":1,"step":1}}
@@ -1 +1 @@
-{"type":"session","version":0,"id":"00000000-0000-0000-0000-000000000000","createdAt":0}
+{"type":"session","version":0,"id":"00000000-0000-0000-0000-000000000000","createdAt":0,"delegationDepth":0}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"669e8682-49fc-4dff-9bc7-6280e283cbe4","createdAt":1783962504097,"cwd":"/var/folders/2c/psb0_fmx7hbgz558xjt_f0l00000gn/T/acp-snap-cwd-WxJGUY"}
+{"type":"session","version":0,"id":"669e8682-49fc-4dff-9bc7-6280e283cbe4","createdAt":1783962504097,"cwd":"/var/folders/2c/psb0_fmx7hbgz558xjt_f0l00000gn/T/acp-snap-cwd-WxJGUY","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783962504115,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783962504117,"data":{"content":[{"type":"text","text":"Call the bash tool to run exactly: echo HELLO. If the first tool result is rejected, retry that command once. Quote the final tool result verbatim and stop."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783962504152,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"0a862642-6652-4916-b88d-b058954ab0c6","createdAt":1783352196657,"cwd":"/tmp/acp-snap-cwd-LEetSL"}
+{"type":"session","version":0,"id":"0a862642-6652-4916-b88d-b058954ab0c6","createdAt":1783352196657,"cwd":"/tmp/acp-snap-cwd-LEetSL","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352196662,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
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@@ -1,4 +1,4 @@
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@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}"}
+{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}","delegationDepth":0}
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@@ -1,4 +1,4 @@
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@@ -1,4 +1,4 @@
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@@ -1,4 +1,4 @@
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@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}"}
+{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}","delegationDepth":0}
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@@ -1,4 +1,4 @@
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@@ -1,4 +1,4 @@
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@@ -1,4 +1,4 @@
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+{"type":"session","version":0,"id":"622d16ce-0a94-476b-97a4-26dad50b1fbf","createdAt":1784086275585,"cwd":"/var/folders/_g/59jgff8x2gqd39f5vy1wnbfc0000gn/T/acp-snap-cwd-Cwf7Bh","delegationDepth":0}
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@@ -1,4 +1,4 @@
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@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}"}
+{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}","delegationDepth":0}
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@@ -1 +1 @@
-{"type":"session","version":0,"id":"00000000-0000-0000-0000-000000000000","createdAt":0}
+{"type":"session","version":0,"id":"00000000-0000-0000-0000-000000000000","createdAt":0,"delegationDepth":0}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}"}
+{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}","delegationDepth":0}
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@@ -1,4 +1,4 @@
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 {"type":"step/start","seq":2,"time":1783654655608,"data":{"turn":1,"step":1}}
@@ -0,0 +1,7 @@
+{
+  "steps": [
+    { "op": "initialize" },
+    { "op": "newSession" },
+    { "op": "prompt", "text": "Delegate through two child generations. The depth-two child must attempt one more subagent call and report the rejection." }
+  ]
+}
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+[
+  {
+    "kind": "chunks",
+    "chunks": [
+      { "type": "block-start", "index": 0, "blockType": "tool-call" },
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+      { "type": "block-end", "index": 0, "block": { "type": "tool-call", "id": "call_root_child", "name": "subagent", "arguments": "{\"description\":\"Start depth one\",\"prompt\":\"Call subagent once. Ask that child to attempt one further subagent call, then report the result.\"}" } },
+      { "type": "usage", "usage": { "inputTokens": 10, "outputTokens": 5 } },
+      { "type": "finish", "reason": { "kind": "tool-calls" } }
+    ]
+  },
+  {
+    "kind": "chunks",
+    "chunks": [
+      { "type": "block-start", "index": 0, "blockType": "text" },
+      { "type": "text-delta", "index": 0, "text": "ROOT_DONE" },
+      { "type": "block-end", "index": 0, "block": { "type": "text", "text": "ROOT_DONE" } },
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+      { "type": "finish", "reason": { "kind": "stop" } }
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+{"type":"assistant/message","seq":19,"time":1784540790365,"data":{"turn":1,"step":2,"content":[{"type":"text","text":"DEPTH_ONE_DONE"}],"provenance":{"provider":"deepseek","model":"deepseek-v4-flash"},"usage":{"inputTokens":10,"outputTokens":2}},"sourceEventSeqs":[14,15,16,17,18],"surfaceOp":"append"}
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+{"type":"turn/start","seq":0,"time":1784540790319,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
+{"type":"user/message","seq":1,"time":1784540790319,"data":{"content":[{"type":"text","text":"Attempt one subagent call beyond the configured cap, then report the rejection."}],"source":{"kind":"user"}},"surfaceOp":"append"}
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+{"type":"assistant/chunk","seq":8,"time":0,"data":{"turn":1,"step":1,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
+{"type":"assistant/message","seq":9,"time":1784540790335,"data":{"turn":1,"step":1,"content":[{"type":"tool-call","id":"call_depth_three_rejected","name":"subagent","arguments":"{\"description\":\"Exceed depth cap\",\"prompt\":\"This child must never start.\"}"}],"provenance":{"provider":"deepseek","model":"deepseek-v4-flash"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[4,5,6,7,8],"surfaceOp":"append"}
+{"type":"tool/call","seq":10,"time":1784540790335,"data":{"turn":1,"step":1,"callId":"call_depth_three_rejected","name":"subagent","arguments":"{\"description\":\"Exceed depth cap\",\"prompt\":\"This child must never start.\"}"}}
+{"type":"tool/result","seq":11,"time":1784540790337,"data":{"turn":1,"step":1,"callId":"call_depth_three_rejected","content":[{"type":"text","text":"Error: subagent depth 3 exceeds maxDepth 2"}],"isError":true},"sourceEventSeqs":[10],"surfaceOp":"append"}
+{"type":"step/end","seq":12,"time":1784540790338,"data":{"turn":1,"step":1}}
+{"type":"step/start","seq":13,"time":1784540790338,"data":{"turn":1,"step":2}}
+{"type":"assistant/chunk","seq":14,"time":1784540790339,"data":{"turn":1,"step":2,"chunk":{"type":"block-start","index":0,"blockType":"text"}}}
+{"type":"assistant/chunk","seq":15,"time":1784540790339,"data":{"turn":1,"step":2,"chunk":{"type":"text-delta","index":0,"text":"DEPTH_REJECTED"}}}
+{"type":"assistant/chunk","seq":16,"time":1784540790339,"data":{"turn":1,"step":2,"chunk":{"type":"block-end","index":0,"block":{"type":"text","text":"DEPTH_REJECTED"}}}}
+{"type":"assistant/chunk","seq":17,"time":1784540790339,"data":{"turn":1,"step":2,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":2}}}}
+{"type":"assistant/chunk","seq":18,"time":1784540790339,"data":{"turn":1,"step":2,"chunk":{"type":"finish","reason":{"kind":"stop"}}}}
+{"type":"assistant/message","seq":19,"time":1784540790339,"data":{"turn":1,"step":2,"content":[{"type":"text","text":"DEPTH_REJECTED"}],"provenance":{"provider":"deepseek","model":"deepseek-v4-flash"},"usage":{"inputTokens":10,"outputTokens":2}},"sourceEventSeqs":[14,15,16,17,18],"surfaceOp":"append"}
+{"type":"step/end","seq":20,"time":1784540790339,"data":{"turn":1,"step":2}}
+{"type":"turn/end","seq":21,"time":1784540790339,"data":{"turn":1,"reason":{"kind":"completed"}}}
@@ -0,0 +1,23 @@
+{"type":"session","version":0,"id":"11111111-1111-4111-8111-111111111111","createdAt":1000,"cwd":"/tmp/subagent-depth-two","delegationDepth":0}
+{"type":"turn/start","seq":0,"time":1784540790290,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
+{"type":"user/message","seq":1,"time":1784540790291,"data":{"content":[{"type":"text","text":"Delegate through two child generations. The depth-two child must attempt one more subagent call and report the rejection."}],"source":{"kind":"user"}},"surfaceOp":"append"}
+{"type":"step/start","seq":2,"time":1784540790308,"data":{"turn":1,"step":1}}
+{"type":"request/header","seq":3,"time":1784540790308,"data":{"header":{"config":{"provider":"deepseek","model":"deepseek-v4-flash"},"system":"{{system}}","tools":"{{tools}}"},"reason":"initial"}}
+{"type":"assistant/chunk","seq":4,"time":1784540790309,"data":{"turn":1,"step":1,"chunk":{"type":"block-start","index":0,"blockType":"tool-call"}}}
+{"type":"assistant/chunk","seq":5,"time":1784540790309,"data":{"turn":1,"step":1,"chunk":{"type":"tool-call-delta","index":0,"id":"call_root_child","name":"subagent","argumentsDelta":"{\"description\":\"Start depth one\",\"prompt\":\"Call subagent once. Ask that child to attempt one further subagent call, then report the result.\"}"}}}
+{"type":"assistant/chunk","seq":6,"time":1784540790309,"data":{"turn":1,"step":1,"chunk":{"type":"block-end","index":0,"block":{"type":"tool-call","id":"call_root_child","name":"subagent","arguments":"{\"description\":\"Start depth one\",\"prompt\":\"Call subagent once. Ask that child to attempt one further subagent call, then report the result.\"}"}}}}
+{"type":"assistant/chunk","seq":7,"time":1784540790309,"data":{"turn":1,"step":1,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":5}}}}
+{"type":"assistant/chunk","seq":8,"time":1784540790309,"data":{"turn":1,"step":1,"chunk":{"type":"finish","reason":{"kind":"tool-calls"}}}}
+{"type":"assistant/message","seq":9,"time":1784540790310,"data":{"turn":1,"step":1,"content":[{"type":"tool-call","id":"call_root_child","name":"subagent","arguments":"{\"description\":\"Start depth one\",\"prompt\":\"Call subagent once. Ask that child to attempt one further subagent call, then report the result.\"}"}],"provenance":{"provider":"deepseek","model":"deepseek-v4-flash"},"usage":{"inputTokens":10,"outputTokens":5}},"sourceEventSeqs":[4,5,6,7,8],"surfaceOp":"append"}
+{"type":"tool/call","seq":10,"time":1784540790310,"data":{"turn":1,"step":1,"callId":"call_root_child","name":"subagent","arguments":"{\"description\":\"Start depth one\",\"prompt\":\"Call subagent once. Ask that child to attempt one further subagent call, then report the result.\"}"}}
+{"type":"tool/result","seq":11,"time":1784540790381,"data":{"turn":1,"step":1,"callId":"call_root_child","content":[{"type":"text","text":"DEPTH_ONE_DONE"}],"isError":false},"sourceEventSeqs":[10],"surfaceOp":"append"}
+{"type":"step/end","seq":12,"time":1784540790382,"data":{"turn":1,"step":1}}
+{"type":"step/start","seq":13,"time":1784540790382,"data":{"turn":1,"step":2}}
+{"type":"assistant/chunk","seq":14,"time":1784540790383,"data":{"turn":1,"step":2,"chunk":{"type":"block-start","index":0,"blockType":"text"}}}
+{"type":"assistant/chunk","seq":15,"time":1784540790383,"data":{"turn":1,"step":2,"chunk":{"type":"text-delta","index":0,"text":"ROOT_DONE"}}}
+{"type":"assistant/chunk","seq":16,"time":1784540790383,"data":{"turn":1,"step":2,"chunk":{"type":"block-end","index":0,"block":{"type":"text","text":"ROOT_DONE"}}}}
+{"type":"assistant/chunk","seq":17,"time":1784540790383,"data":{"turn":1,"step":2,"chunk":{"type":"usage","usage":{"inputTokens":10,"outputTokens":2}}}}
+{"type":"assistant/chunk","seq":18,"time":1784540790383,"data":{"turn":1,"step":2,"chunk":{"type":"finish","reason":{"kind":"stop"}}}}
+{"type":"assistant/message","seq":19,"time":1784540790383,"data":{"turn":1,"step":2,"content":[{"type":"text","text":"ROOT_DONE"}],"provenance":{"provider":"deepseek","model":"deepseek-v4-flash"},"usage":{"inputTokens":10,"outputTokens":2}},"sourceEventSeqs":[14,15,16,17,18],"surfaceOp":"append"}
+{"type":"step/end","seq":20,"time":1784540790383,"data":{"turn":1,"step":2}}
+{"type":"turn/end","seq":21,"time":1784540790383,"data":{"turn":1,"reason":{"kind":"completed"}}}
@@ -0,0 +1,6 @@
+{"jsonrpc":"2.0","id":1,"result":{"protocolVersion":1,"agentInfo":{"name":"deepseek-harness-acp","version":"0.0.1"},"agentCapabilities":{"loadSession":true,"promptCapabilities":{"image":false,"audio":false,"embeddedContext":false}},"authMethods":[]}}
+{"jsonrpc":"2.0","id":2,"result":{"sessionId":"{{sessionId}}","configOptions":[{"id":"model","name":"Model","description":"Sets this session's provider and model.","category":"model","type":"select","currentValue":"[\"deepseek\",\"deepseek-v4-flash\"]","options":[{"value":"[\"deepseek\",\"deepseek-v4-flash\"]","name":"deepseek-v4-flash"},{"value":"[\"deepseek\",\"deepseek-v4-pro\"]","name":"deepseek-v4-pro"}]},{"id":"permission","name":"Permissions","description":"The session permission preset: each choice bundles a sandbox mode and an approval policy.","category":"mode","type":"select","currentValue":"danger-full-access","options":[{"value":"workspace-write","name":"workspace-write","description":"Write inside the workspace and permitted temporary directories; wider retries require approval."},{"value":"danger-full-access","name":"danger-full-access","description":"Full file access without approval prompts."}]}]}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call","toolCallId":"call_root_child","title":"subagent","kind":"other","status":"in_progress","rawInput":{"description":"Start depth one","prompt":"Call subagent once. Ask that child to attempt one further subagent call, then report the result."}}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"tool_call_update","toolCallId":"call_root_child","status":"completed","content":[{"type":"content","content":{"type":"text","text":"DEPTH_ONE_DONE"}}]}}}
+{"jsonrpc":"2.0","method":"session/update","params":{"sessionId":"{{sessionId}}","update":{"sessionUpdate":"agent_message_chunk","content":{"type":"text","text":"ROOT_DONE"}}}}
+{"jsonrpc":"2.0","id":3,"result":{"stopReason":"end_turn"}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"ada8966c-9fa3-441b-8721-37ff1e795e6a","createdAt":1783352137161,"cwd":"/tmp/acp-snap-cwd-0HLtcD","parentSession":"96cf59c9-b347-48b9-b234-a5200913ad05","seedLength":37}
+{"type":"session","version":0,"id":"ada8966c-9fa3-441b-8721-37ff1e795e6a","createdAt":1783352137161,"cwd":"/tmp/acp-snap-cwd-0HLtcD","parentSession":"96cf59c9-b347-48b9-b234-a5200913ad05","seedLength":37,"delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783352134837,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352134838,"data":{"content":[{"type":"text","text":"Remember this fact for later: the project codeword is MARMALADE. Reply with the single word OK and stop. Do not use any tools."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352134840,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"96cf59c9-b347-48b9-b234-a5200913ad05","createdAt":1783352134832,"cwd":"/tmp/acp-snap-cwd-0HLtcD"}
+{"type":"session","version":0,"id":"96cf59c9-b347-48b9-b234-a5200913ad05","createdAt":1783352134832,"cwd":"/tmp/acp-snap-cwd-0HLtcD","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352134837,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352134838,"data":{"content":[{"type":"text","text":"Remember this fact for later: the project codeword is MARMALADE. Reply with the single word OK and stop. Do not use any tools."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352134840,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"e4aafa18-b9e3-48d0-8aae-6c9b25dcae80","createdAt":1783352145223,"cwd":"/tmp/acp-snap-cwd-i43JSF","parentSession":"959ffdf5-03e2-465e-9482-009b704632dc"}
+{"type":"session","version":0,"id":"e4aafa18-b9e3-48d0-8aae-6c9b25dcae80","createdAt":1783352145223,"cwd":"/tmp/acp-snap-cwd-i43JSF","parentSession":"959ffdf5-03e2-465e-9482-009b704632dc","delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783352145224,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352145224,"data":{"content":[{"type":"text","text":"Reply with exactly the word ALPHA and nothing else."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352145224,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"02b3a8dd-1d5e-4866-825f-5fbf5000a632","createdAt":1783352147504,"cwd":"/tmp/acp-snap-cwd-i43JSF","parentSession":"959ffdf5-03e2-465e-9482-009b704632dc","seedLength":31}
+{"type":"session","version":0,"id":"02b3a8dd-1d5e-4866-825f-5fbf5000a632","createdAt":1783352147504,"cwd":"/tmp/acp-snap-cwd-i43JSF","parentSession":"959ffdf5-03e2-465e-9482-009b704632dc","seedLength":31,"delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783352142834,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352142834,"data":{"content":[{"type":"text","text":"Remember this fact for later: the project codeword is SAFFRON. Reply with the single word OK and stop. Do not use any tools."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352142835,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"959ffdf5-03e2-465e-9482-009b704632dc","createdAt":1783352142830,"cwd":"/tmp/acp-snap-cwd-i43JSF"}
+{"type":"session","version":0,"id":"959ffdf5-03e2-465e-9482-009b704632dc","createdAt":1783352142830,"cwd":"/tmp/acp-snap-cwd-i43JSF","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352142834,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352142834,"data":{"content":[{"type":"text","text":"Remember this fact for later: the project codeword is SAFFRON. Reply with the single word OK and stop. Do not use any tools."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352142835,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"553f8e92-aac1-4df3-8657-eacbb58f9581","createdAt":1783352127669,"cwd":"/tmp/acp-snap-cwd-28z5Of","parentSession":"14dda109-5728-45ba-a002-7db9543fe50e"}
+{"type":"session","version":0,"id":"553f8e92-aac1-4df3-8657-eacbb58f9581","createdAt":1783352127669,"cwd":"/tmp/acp-snap-cwd-28z5Of","parentSession":"14dda109-5728-45ba-a002-7db9543fe50e","delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783352127670,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352127670,"data":{"content":[{"type":"text","text":"Reply with exactly the word ALPHA and nothing else."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352127671,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"5f49e80c-16fc-42c7-a617-0b6bd0680aa3","createdAt":1783352129662,"cwd":"/tmp/acp-snap-cwd-28z5Of","parentSession":"14dda109-5728-45ba-a002-7db9543fe50e"}
+{"type":"session","version":0,"id":"5f49e80c-16fc-42c7-a617-0b6bd0680aa3","createdAt":1783352129662,"cwd":"/tmp/acp-snap-cwd-28z5Of","parentSession":"14dda109-5728-45ba-a002-7db9543fe50e","delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783352129662,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352129662,"data":{"content":[{"type":"text","text":"Reply with exactly the word BETA and nothing else."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352129663,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"14dda109-5728-45ba-a002-7db9543fe50e","createdAt":1783352126247,"cwd":"/tmp/acp-snap-cwd-28z5Of"}
+{"type":"session","version":0,"id":"14dda109-5728-45ba-a002-7db9543fe50e","createdAt":1783352126247,"cwd":"/tmp/acp-snap-cwd-28z5Of","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352126251,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352126251,"data":{"content":[{"type":"text","text":"Use the subagent tool TWICE, once at a time, to delegate two subtasks to child agents. First subtask: 'Reply with exactly the word ALPHA and nothing else.' Second subtask (after the first returns): 'Reply with exactly the word BETA and nothing else.' After both subagents return, reply with the single word PARENT_DONE and stop. Do not use the bash tool."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352126252,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"ea339828-7885-42e1-9083-4355e6f1708d","createdAt":1783352120855,"cwd":"/tmp/acp-snap-cwd-rbeWyt","parentSession":"5138ed0d-e86e-4a7d-b75b-803307e92b17"}
+{"type":"session","version":0,"id":"ea339828-7885-42e1-9083-4355e6f1708d","createdAt":1783352120855,"cwd":"/tmp/acp-snap-cwd-rbeWyt","parentSession":"5138ed0d-e86e-4a7d-b75b-803307e92b17","delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783352120856,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352120856,"data":{"content":[{"type":"text","text":"Reply with exactly the word CHILD_OK and nothing else."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352120856,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"5138ed0d-e86e-4a7d-b75b-803307e92b17","createdAt":1783352119267,"cwd":"/tmp/acp-snap-cwd-rbeWyt"}
+{"type":"session","version":0,"id":"5138ed0d-e86e-4a7d-b75b-803307e92b17","createdAt":1783352119267,"cwd":"/tmp/acp-snap-cwd-rbeWyt","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352119273,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352119274,"data":{"content":[{"type":"text","text":"Use the subagent tool exactly once to delegate this subtask to a child agent: 'Reply with exactly the word CHILD_OK and nothing else.' After the subagent returns, reply with the single word PARENT_DONE and stop. Do not use the bash tool."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352119275,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"539aa64c-7f37-40ff-abd8-ed45b717be1b","createdAt":1783600629539,"cwd":"/var/folders/bn/vj1dvck95yd5jh3x4wskflxm0000gn/T/acp-snap-cwd-ka5r8w"}
+{"type":"session","version":0,"id":"539aa64c-7f37-40ff-abd8-ed45b717be1b","createdAt":1783600629539,"cwd":"/var/folders/bn/vj1dvck95yd5jh3x4wskflxm0000gn/T/acp-snap-cwd-ka5r8w","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783600629541,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783600629541,"data":{"content":[{"type":"text","text":"Reply with exactly the word: PONG. Do not use any tools."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783600629542,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"b0f1f758-dcf0-474e-851d-e62c11ec0a09","createdAt":1783352057652,"cwd":"/tmp/acp-snap-cwd-AYilT7"}
+{"type":"session","version":0,"id":"b0f1f758-dcf0-474e-851d-e62c11ec0a09","createdAt":1783352057652,"cwd":"/tmp/acp-snap-cwd-AYilT7","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352057655,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352057655,"data":{"content":[{"type":"text","text":"Use the todo_write tool to record a plan with exactly three todos: \"read the code\" (in_progress), \"write the fix\" (pending), \"run the tests\" (pending). Send all three in one todo_write call. Then reply with the single word DONE and stop."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352057657,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"e9421ff4-baae-4807-a7ea-fd8a65f2c897","createdAt":1783352044766,"cwd":"/tmp/acp-snap-cwd-OwUkBh"}
+{"type":"session","version":0,"id":"e9421ff4-baae-4807-a7ea-fd8a65f2c897","createdAt":1783352044766,"cwd":"/tmp/acp-snap-cwd-OwUkBh","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352044771,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352044771,"data":{"content":[{"type":"text","text":"Use the bash tool to run exactly: echo SNAPSHOT_OK. Then reply with the single word DONE and stop."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352044773,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"583a4db2-3350-436c-b4a5-5615fd159052","createdAt":1783600636316,"cwd":"/var/folders/bn/vj1dvck95yd5jh3x4wskflxm0000gn/T/acp-snap-cwd-vdJYjz","parentSession":"3fd7d599-56b1-493a-930d-f1fc5e1556e8"}
+{"type":"session","version":0,"id":"583a4db2-3350-436c-b4a5-5615fd159052","createdAt":1783600636316,"cwd":"/var/folders/bn/vj1dvck95yd5jh3x4wskflxm0000gn/T/acp-snap-cwd-vdJYjz","parentSession":"3fd7d599-56b1-493a-930d-f1fc5e1556e8","delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783600636316,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783600636316,"data":{"content":[{"type":"text","text":"Reply with exactly the word WF_CHILD_OK and nothing else."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783600636316,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"3fd7d599-56b1-493a-930d-f1fc5e1556e8","createdAt":1783600631835,"cwd":"/var/folders/bn/vj1dvck95yd5jh3x4wskflxm0000gn/T/acp-snap-cwd-vdJYjz"}
+{"type":"session","version":0,"id":"3fd7d599-56b1-493a-930d-f1fc5e1556e8","createdAt":1783600631835,"cwd":"/var/folders/bn/vj1dvck95yd5jh3x4wskflxm0000gn/T/acp-snap-cwd-vdJYjz","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783600631838,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783600631838,"data":{"content":[{"type":"text","text":"Use the workflow tool exactly once, with args omitted, meta set to { \"name\": \"snapshot-flow\", \"description\": \"one child for the snapshot\" }, and this EXACT script body (copy it verbatim):\nphase('Run')\nconst reply = await agent('Reply with exactly the word WF_CHILD_OK and nothing else.')\nreturn { reply }\nAfter the workflow returns, reply with the single word WORKFLOW_DONE and stop. Do not use any other tool."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783600631839,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}"}
+{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783778297065,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783778297066,"data":{"content":[{"type":"text","text":"Read nested/task.txt with the read tool, then reply DONE."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783778297069,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"48aca674-000a-4583-810b-01f8785cef13","createdAt":1783352264076,"cwd":"/tmp/acp-snap-cwd-rxbEpP"}
+{"type":"session","version":0,"id":"48aca674-000a-4583-810b-01f8785cef13","createdAt":1783352264076,"cwd":"/tmp/acp-snap-cwd-rxbEpP","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352264080,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352264081,"data":{"content":[{"type":"text","text":"A file named greeting.txt in the current directory contains one word. Use the bash tool to append a second line containing the word WORLD to it (so it has two lines), then read the file back with `cat greeting.txt` to confirm, and reply with the single word DONE. Use a single bash call per action."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352264082,"data":{"turn":1,"step":1}}
@@ -65,12 +65,14 @@
  config:
    provider: spawn
    toolName: subagent
+    maxDepth: 1

 - id: tool-subagent-fork
  name: '@deepseek-ai/dsh-tool-subagent'
  config:
    provider: fork
    toolName: subagent_fork
+    maxDepth: 1

 # The worker-thread workflow engine fans a model-written JavaScript script's
 # `agent()` calls out through the spawn backend.
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"22222222-2222-4222-8222-222222222222","createdAt":1783950001000,"cwd":"/tmp/advanced-headless","parentSession":"11111111-1111-4111-8111-111111111111"}
+{"type":"session","version":0,"id":"22222222-2222-4222-8222-222222222222","createdAt":1783950001000,"cwd":"/tmp/advanced-headless","parentSession":"11111111-1111-4111-8111-111111111111","delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783957884563,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783957884563,"data":{"content":[{"type":"text","text":"Reply with exactly DIRECT_CHILD_OK and nothing else."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783957884564,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"33333333-3333-4333-8333-333333333333","createdAt":1783950002000,"cwd":"/tmp/advanced-headless","parentSession":"11111111-1111-4111-8111-111111111111"}
+{"type":"session","version":0,"id":"33333333-3333-4333-8333-333333333333","createdAt":1783950002000,"cwd":"/tmp/advanced-headless","parentSession":"11111111-1111-4111-8111-111111111111","delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783957884700,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783957884700,"data":{"content":[{"type":"text","text":"Reply with exactly WORKFLOW_CHILD_OK and nothing else."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783957884700,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"11111111-1111-4111-8111-111111111111","createdAt":1783950000000,"cwd":"/tmp/advanced-headless"}
+{"type":"session","version":0,"id":"11111111-1111-4111-8111-111111111111","createdAt":1783950000000,"cwd":"/tmp/advanced-headless","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783957884479,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783957884479,"data":{"content":[{"type":"text","text":"Run this advanced flow exactly once: mount a no-op Cordis plugin named snapshot-marker; use run_code to inspect the live dynamic mounts through tools.cordis_inspect; delegate once to a direct spawn child; run one workflow that delegates to another spawn child; unmount dyn-1; then reply with exactly ADVANCED_HEADLESS_OK."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783957884486,"data":{"turn":1,"step":1}}
@@ -81,12 +81,14 @@
  config:
    provider: spawn
    toolName: subagent
+    maxDepth: 1

 - id: tool-subagent-fork
  name: '@deepseek-ai/dsh-tool-subagent'
  config:
    provider: fork
    toolName: subagent_fork
+    maxDepth: 1


 # The worker-thread workflow engine fans a model-written JavaScript script's
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"e128dda9-ed11-4868-8266-0ef90d03c3d6","createdAt":1783352050748,"cwd":"/tmp/acp-snap-cwd-mrFUuk"}
+{"type":"session","version":0,"id":"e128dda9-ed11-4868-8266-0ef90d03c3d6","createdAt":1783352050748,"cwd":"/tmp/acp-snap-cwd-mrFUuk","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352050753,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352050753,"data":{"content":[{"type":"text","text":"Use the bash tool to run exactly: echo TERMINAL_OK. Then reply with the single word DONE and stop."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352050755,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"94cd1ae4-e1d1-4ec8-9d27-50a1f849b6b3","createdAt":1783611771392,"cwd":"/var/folders/2c/psb0_fmx7hbgz558xjt_f0l00000gn/T/acp-snap-cwd-BteTVR"}
+{"type":"session","version":0,"id":"94cd1ae4-e1d1-4ec8-9d27-50a1f849b6b3","createdAt":1783611771392,"cwd":"/var/folders/2c/psb0_fmx7hbgz558xjt_f0l00000gn/T/acp-snap-cwd-BteTVR","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783611771394,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783611771394,"data":{"content":[{"type":"text","text":"Using ONE run_code program: call the bash tool twice — exactly `echo CODE_ONE` then exactly `echo CODE_TWO` — and return the two outputs joined with a plus sign. Then reply with that joined string only and stop."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783611771396,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"22222222-2222-4222-8222-222222222222","createdAt":1783950001000,"cwd":"/tmp/advanced-acp","parentSession":"11111111-1111-4111-8111-111111111111"}
+{"type":"session","version":0,"id":"22222222-2222-4222-8222-222222222222","createdAt":1783950001000,"cwd":"/tmp/advanced-acp","parentSession":"11111111-1111-4111-8111-111111111111","delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783957884563,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783957884563,"data":{"content":[{"type":"text","text":"Reply with exactly DIRECT_CHILD_OK and nothing else."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783957884564,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"33333333-3333-4333-8333-333333333333","createdAt":1783950002000,"cwd":"/tmp/advanced-acp","parentSession":"11111111-1111-4111-8111-111111111111"}
+{"type":"session","version":0,"id":"33333333-3333-4333-8333-333333333333","createdAt":1783950002000,"cwd":"/tmp/advanced-acp","parentSession":"11111111-1111-4111-8111-111111111111","delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783957884700,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783957884700,"data":{"content":[{"type":"text","text":"Reply with exactly WORKFLOW_CHILD_OK and nothing else."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783957884700,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"11111111-1111-4111-8111-111111111111","createdAt":1783950000000,"cwd":"/tmp/advanced-acp"}
+{"type":"session","version":0,"id":"11111111-1111-4111-8111-111111111111","createdAt":1783950000000,"cwd":"/tmp/advanced-acp","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783957884479,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783957884479,"data":{"content":[{"type":"text","text":"Run this advanced flow exactly once: mount a no-op Cordis plugin named snapshot-marker; use run_code to inspect the live dynamic mounts through tools.cordis_inspect; delegate once to a direct spawn child; run one workflow that delegates to another spawn child; unmount dyn-1; then reply with exactly ADVANCED_ACP_OK."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783957884486,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"583a4db2-3350-436c-b4a5-5615fd159052","createdAt":1783600636316,"cwd":"/var/folders/bn/vj1dvck95yd5jh3x4wskflxm0000gn/T/acp-snap-cwd-vdJYjz","parentSession":"3fd7d599-56b1-493a-930d-f1fc5e1556e8"}
+{"type":"session","version":0,"id":"583a4db2-3350-436c-b4a5-5615fd159052","createdAt":1783600636316,"cwd":"/var/folders/bn/vj1dvck95yd5jh3x4wskflxm0000gn/T/acp-snap-cwd-vdJYjz","parentSession":"3fd7d599-56b1-493a-930d-f1fc5e1556e8","delegationDepth":1}
 {"type":"turn/start","seq":0,"time":1783600636316,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783600636316,"data":{"content":[{"type":"text","text":"Reply with exactly the word WF_CHILD_OK and nothing else."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783600636316,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"3fd7d599-56b1-493a-930d-f1fc5e1556e8","createdAt":1783600631835,"cwd":"/var/folders/bn/vj1dvck95yd5jh3x4wskflxm0000gn/T/acp-snap-cwd-vdJYjz"}
+{"type":"session","version":0,"id":"3fd7d599-56b1-493a-930d-f1fc5e1556e8","createdAt":1783600631835,"cwd":"/var/folders/bn/vj1dvck95yd5jh3x4wskflxm0000gn/T/acp-snap-cwd-vdJYjz","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783600631838,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783600631838,"data":{"content":[{"type":"text","text":"Use the workflow tool exactly once, with args omitted, meta set to { \"name\": \"snapshot-flow\", \"description\": \"one child for the snapshot\" }, and this EXACT script body (copy it verbatim):\nphase('Run')\nconst reply = await agent('Reply with exactly the word WF_CHILD_OK and nothing else.')\nreturn { reply }\nAfter the workflow returns, reply with the single word WORKFLOW_DONE and stop. Do not use any other tool."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783600631839,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"228b7b82-84ed-49b7-a567-981c03b28c77","createdAt":1783352113760,"cwd":"/tmp/acp-snap-cwd-aN2GRR"}
+{"type":"session","version":0,"id":"228b7b82-84ed-49b7-a567-981c03b28c77","createdAt":1783352113760,"cwd":"/tmp/acp-snap-cwd-aN2GRR","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352113765,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352113765,"data":{"content":[{"type":"text","text":"Reply with exactly the word: ONE. No tools."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352113767,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}"}
+{"type":"session","version":0,"id":"{{sessionId}}","createdAt":0,"cwd":"{{cwd}}","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":0,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":0,"data":{"content":[{"type":"text","text":"Use the read tool twice in the same assistant message: read a.txt and b.txt. Then reply DONE."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":0,"data":{"turn":1,"step":1}}
@@ -1,4 +1,4 @@
-{"type":"session","version":0,"id":"b0f1f758-dcf0-474e-851d-e62c11ec0a09","createdAt":1783352057652,"cwd":"/tmp/acp-snap-cwd-AYilT7"}
+{"type":"session","version":0,"id":"b0f1f758-dcf0-474e-851d-e62c11ec0a09","createdAt":1783352057652,"cwd":"/tmp/acp-snap-cwd-AYilT7","delegationDepth":0}
 {"type":"turn/start","seq":0,"time":1783352057655,"data":{"turn":1,"trigger":{"kind":"message","source":{"kind":"user"}}}}
 {"type":"user/message","seq":1,"time":1783352057655,"data":{"content":[{"type":"text","text":"Use the todo_write tool to record a plan with exactly three todos: \"read the code\" (in_progress), \"write the fix\" (pending), \"run the tests\" (pending). Send all three in one todo_write call. Then reply with the single word DONE and stop."}],"source":{"kind":"user"}},"surfaceOp":"append"}
 {"type":"step/start","seq":2,"time":1783352057657,"data":{"turn":1,"step":1}}
@@ -367,7 +367,7 @@ export const SERVICE_API: readonly ServiceApiEntry[] = [
    methods: [
      {
        signature: 'create(id?: SessionId, options?: CreateSessionOptions): Session',
-        jsDoc: '/**\n * Create a session owned by the calling fiber: disposing that fiber stops\n * event notification and removes the session from the store. `options.seed`\n * populates the session with a copy of those events (replay/fork);\n * `options.meta` attaches creation metadata (validated absolute `cwd`,\n * `parentSession` lineage) as the immutable {@link SessionHeader} (the store\n * fills `version`/`id`/`createdAt`).\n *\n * For an agent whose session must be torn down IN ORDER with its loop (so the\n * loop\'s final flush is captured before the store attachment ends), do NOT use this\n * — fold the session lifecycle into the agent\'s own effect via\n * {@link prepare} + {@link enter} + {@link announce} (see\n * `dsh-agent-loop`\'s creation transaction).\n *\n * @param id - the session id; omitted, the store mints `session-<n>`.\n * @param options - seed events and/or creation metadata for the header.\n * @returns the live session, already entered and announced.\n * @throws if a session with `id` already exists, metadata is not a plain\n *   lossless-JSON record with valid scalar fields, or `meta.cwd` is a\n *   non-absolute path (storage backends key directories off it).\n */',
+        jsDoc: '/**\n * Create a session owned by the calling fiber: disposing that fiber stops\n * event notification and removes the session from the store. `options.seed`\n * populates the session with a copy of those events (replay/fork);\n * `options.meta` attaches creation metadata (validated absolute `cwd`, seed\n * and parent lineage, and delegation depth) as the immutable\n * {@link SessionHeader} (the store fills `version`/`id`/`createdAt`).\n *\n * For an agent whose session must be torn down IN ORDER with its loop (so the\n * loop\'s final flush is captured before the store attachment ends), do NOT use this\n * — fold the session lifecycle into the agent\'s own effect via\n * {@link prepare} + {@link enter} + {@link announce} (see\n * `dsh-agent-loop`\'s creation transaction).\n *\n * @param id - the session id; omitted, the store mints `session-<n>`.\n * @param options - seed events and/or creation metadata for the header.\n * @returns the live session, already entered and announced.\n * @throws if a session with `id` already exists, metadata is not a plain\n *   lossless-JSON record with valid scalar fields, or `meta.cwd` is a\n *   non-absolute path (storage backends key directories off it).\n */',
      },
      {
        signature: 'prepare(id?: SessionId, options?: CreateSessionOptions): Session',
@@ -1093,11 +1093,11 @@ export const TYPE_API: readonly TypeApiEntry[] = [
  },
  {
    name: 'CreateAgentOptions',
-    declaration: 'export interface CreateAgentOptions {\n    readonly sessionId: SessionId;\n    readonly meta?: {\n        readonly cwd?: string;\n        readonly parentSession?: SessionId;\n        readonly seedLength?: number;\n    };\n    readonly seed?: readonly SessionEvent[];\n    readonly agentOptions?: AgentOptions;\n    readonly signal?: AbortSignal;\n    readonly setup?: (agentCtx: Context) => Promise<void> | void;\n}',
+    declaration: 'export interface CreateAgentOptions {\n    readonly sessionId: SessionId;\n    readonly meta?: {\n        readonly cwd?: string;\n        readonly parentSession?: SessionId;\n        readonly seedLength?: number;\n        readonly delegationDepth?: number;\n    };\n    readonly seed?: readonly SessionEvent[];\n    readonly agentOptions?: AgentOptions;\n    readonly signal?: AbortSignal;\n    readonly setup?: (agentCtx: Context) => Promise<void> | void;\n}',
  },
  {
    name: 'CreateSessionOptions',
-    declaration: 'export interface CreateSessionOptions {\n    readonly seed?: readonly SessionEvent[];\n    readonly meta?: {\n        readonly cwd?: string;\n        readonly parentSession?: SessionId;\n        readonly createdAt?: number;\n        readonly seedLength?: number;\n    };\n}',
+    declaration: 'export interface CreateSessionOptions {\n    readonly seed?: readonly SessionEvent[];\n    readonly meta?: {\n        readonly cwd?: string;\n        readonly parentSession?: SessionId;\n        readonly createdAt?: number;\n        readonly seedLength?: number;\n        readonly delegationDepth?: number;\n    };\n}',
  },
  {
    name: 'DiffCallView',
@@ -1321,7 +1321,7 @@ export const TYPE_API: readonly TypeApiEntry[] = [
  },
  {
    name: 'SessionHeader',
-    declaration: 'export interface SessionHeader {\n    readonly version: number;\n    readonly id: SessionId;\n    readonly createdAt: number;\n    readonly cwd?: string;\n    readonly parentSession?: SessionId;\n    readonly seedLength?: number;\n}',
+    declaration: 'export interface SessionHeader {\n    readonly version: number;\n    readonly id: SessionId;\n    readonly createdAt: number;\n    readonly cwd?: string;\n    readonly parentSession?: SessionId;\n    readonly seedLength?: number;\n    readonly delegationDepth?: number;\n}',
  },
  {
    name: 'SessionId',
@@ -620,12 +620,7 @@ export class AgentLoop extends Service implements AgentFactory {
      transaction.assertActive()
      const session = this.runtime.ctx.sessions.prepare(options.resumeSessionId, {
        seed: loaded.events,
-        meta: {
-          createdAt: loaded.meta.createdAt,
-          ...loaded.meta.cwd === undefined ? {} : { cwd: loaded.meta.cwd },
-          ...loaded.meta.parentSession === undefined ? {} : { parentSession: loaded.meta.parentSession },
-          ...loaded.meta.seedLength === undefined ? {} : { seedLength: loaded.meta.seedLength },
-        },
+        meta: loaded.meta,
      })
      const agent = transaction.prepare(agentOptions, session, this.maxParallelToolCalls)
      await transaction.waitFor(options.setup?.(agent.ctx))
@@ -411,7 +411,7 @@ describe('the session-persistence Agent Note: AgentLoop factory create/resume',
    await ctx.fiber.dispose()
  })

-  it('resume of a forked session preserves the parentSession lineage and seed boundary in the header', async () => {
+  it('resume of a forked session preserves the lineage, seed boundary, and delegation depth in the header', async () => {
    // Lifecycle 1: persist a FORKED session (carries parentSession + seedLength
    // in its header) by creating it with a complete-turn seed — the write path
    // materializes the fork (header + seed) on disk.
@@ -423,7 +423,7 @@ describe('the session-persistence Agent Note: AgentLoop factory create/resume',
    const { ctx: ctx1, root } = await persistentHarness(adapter1)
    const forked = ctx1.sessions.create(SessionId('forked-sess'), {
      seed,
-      meta: { cwd: '/w', parentSession: SessionId('parent-sess'), seedLength: seed.length },
+      meta: { cwd: '/w', parentSession: SessionId('parent-sess'), seedLength: seed.length, delegationDepth: 1 },
    })
    await ctx1.parallel('session/flush', forked)
    await ctx1.fiber.dispose()
@@ -447,6 +447,9 @@ describe('the session-persistence Agent Note: AgentLoop factory create/resume',
    expect(a2.session.header.parentSession).toBe('parent-sess')
    expect(a2.session.header.cwd).toBe('/w')
    expect(a2.session.header.seedLength).toBe(seed.length)
+    // The recursion budget survives resume — a dropped depth would let a
+    // resumed child delegate as if it were top-level.
+    expect(a2.session.header.delegationDepth).toBe(1)
    await ctx2.fiber.dispose()
  })

@@ -46,15 +46,21 @@ export interface CreateAgentOptions {
  readonly sessionId: SessionId
  /**
   * Session creation metadata: validated absolute `cwd`, `parentSession`
-   * fork lineage, and the `seedLength` seed boundary. Mirrors the
-   * `cwd`/`parentSession`/`seedLength` fields of
+   * fork lineage, the `seedLength` seed boundary, and the `delegationDepth`
+   * recursion budget. Mirrors the
+   * `cwd`/`parentSession`/`seedLength`/`delegationDepth` fields of
   * {@link CreateSessionOptions.meta} in dsh-session (the internal-only
   * `createdAt`, used when reconstructing a persisted session, is deliberately
   * excluded — a factory caller never sets it). This is durable session data,
   * so the session boundary validates and snapshots it before asynchronous
   * setup begins.
   */
-  readonly meta?: { readonly cwd?: string; readonly parentSession?: SessionId; readonly seedLength?: number }
+  readonly meta?: {
+    readonly cwd?: string
+    readonly parentSession?: SessionId
+    readonly seedLength?: number
+    readonly delegationDepth?: number
+  }
  /**
   * Seed events to reconstruct the child session's log from (the fork lineage
   * primitive). When present, the factory creates the session with this event
--- a/Show More
+++ b/Show More