Merge remote-tracking branch 'origin/master' into mergebot/pr711

# Conflicts:
#	apps/cli/README.i18n.yaml
#	apps/cli/README.md
#	apps/cli/README.zh.md
#	apps/cli/cordis.yml
#	apps/cli/package.json
#	docs/config-catalog.md
#	packages/client/runtime/README.i18n.yaml
#	packages/client/runtime/src/client/contract/sessions.ts
#	packages/client/test-runtime/src/sessions.ts
#	packages/client/ui-workspace/README.i18n.yaml
#	packages/client/ui-workspace/README.md
#	packages/client/ui-workspace/README.zh.md
#	packages/client/ui-workspace/src/client/WorkspaceBrowser.tsx
#	packages/client/ui-workspace/src/client/tree.ts
#	packages/client/ui-workspace/tests/apply.spec.ts
#	packages/client/ui-workspace/tests/tree.spec.ts
#	packages/host/apiproxy/README.i18n.yaml
#	packages/host/apiproxy/src/api-proxy.ts
#	packages/host/apiproxy/src/api/index.ts
#	packages/host/apiproxy/tests/client-handler.spec.ts
#	packages/host/apiproxy/tests/rpc-schemas.spec.ts
#	pnpm-lock.yaml

packages/host/apiproxy/src/api-proxy.ts

@@ -9,11 +9,12 @@ import { join } from 'node:path'
 import type { Context } from 'cordis'
 import { installAgentLlmTarget } from '@deepseek-ai/dsh-agent'
 import type {
-  Agent, AgentLlmTarget, AgentLlmTargetRef, AgentStatus, InboxPlacement,
+  Agent, AgentLlmTarget, AgentLlmTargetRef, AgentStatus, InboxItem, InboxItemId,
 } from '@deepseek-ai/dsh-agent'
 import { createUserMessage, ReasoningEffortId } from '@deepseek-ai/dsh-llm'
 import { errorChain } from '@deepseek-ai/dsh-llm'
-import type { MessageId, MessageSource } from '@deepseek-ai/dsh-llm'
+import type { MessageSource } from '@deepseek-ai/dsh-llm'
+import { isAppendSurfaceEvent, lastActivityTime } from '@deepseek-ai/dsh-session'
 import type { Session, SessionEvent, SessionHeader, SessionId, UserMessage } from '@deepseek-ai/dsh-session'
 import type { SessionPersistence } from '@deepseek-ai/dsh-session-persistence'
 import { SessionQueryError, type SessionSearchCursor } from '@deepseek-ai/dsh-session-query'
@@ -71,7 +72,7 @@ const SESSION_SEARCH_PROVIDER_CALL_LIMIT = 100
 /** Bound cold-log stat fan-out and settle each started batch before cancellation returns. */
 const COLD_SUMMARY_BATCH_SIZE = 16
 
-/** Surface message event types (the pagination counting unit). */
+/** Conversation message event types (the pagination counting unit). */
 const MESSAGE_TYPES = new Set(['user/message', 'assistant/message', 'steering/message'])
 
 /** Read live abort state across awaits without treating it as synchronously immutable. */
@@ -80,10 +81,14 @@ function isAborted(signal: AbortSignal): boolean {
 }
 
 /**
- * Message-boundary pagination: count maxMessages surface messages backwards from
- * the window tail; the cut is the starting seq of the oldest message group
- * (chunks group via sourceEventSeqs — never cut mid-message). The tail page
- * naturally includes the in-progress partial.
+ * Message-boundary pagination: count maxMessages append-origin messages
+ * backwards from the window tail. Replacement copies never entered the
+ * conversation a reader sees — they restate a shadowed range for the model
+ * alone — so they consume no quota; the page stays one contiguous raw range,
+ * which keeps a compaction's log-only provenance on the same page as its
+ * replacement. The cut is the starting seq of the oldest message group (chunks
+ * group via sourceEventSeqs — never cut mid-message). The tail page naturally
+ * includes the in-progress partial.
  */
 function paginate(
   events: readonly SessionEvent[],
@@ -95,7 +100,7 @@ function paginate(
   let cut = 0
   for (let i = window.length - 1; i >= 0; i--) {
     const event = window[i] as SessionEvent
-    if (!MESSAGE_TYPES.has(event.type)) continue
+    if (!MESSAGE_TYPES.has(event.type) || !isAppendSurfaceEvent(event)) continue
     count++
     const sources = (event as { sourceEventSeqs?: number[] }).sourceEventSeqs
     const groupStart = sources !== undefined && sources.length > 0 ? Math.min(event.seq, ...sources) : event.seq
@@ -181,7 +186,9 @@ function sessionBlank(session: Session): boolean {
 function summarize(session: Session, running: boolean): SessionSummary {
   return {
     sessionId: session.id,
-    updatedAt: session.events.at(-1)?.time ?? session.header.createdAt,
+    // Excludes end-seed: a resumed-but-untouched session
+    // must not sort as freshly worked in.
+    updatedAt: lastActivityTime(session.events) ?? session.header.createdAt,
     running,
     blank: sessionBlank(session),
     ...session.header.parentSession === undefined ? {} : { parentSessionId: session.header.parentSession },
@@ -532,46 +539,106 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
   })
 
   /**
-   * Per-session inbox occurrence mirror serving the mux-open queue snapshot
+   * Per-session queued-occurrence mirror serving the mux-open queue snapshot
    * (the same refresh-recovery baseline as pending questions). Each terminal
-   * inbox event retires one matching occurrence, so repeated sends of the same
+   * queue event retires one matching occurrence, so repeated sends of the same
    * identified message remain visible until every occurrence is claimed.
    */
-  const queuedMirror = new Map<SessionId, { message: UserMessage; steering: boolean }[]>()
+  const queuedMirror = new Map<SessionId, InboxItem[]>()
+  type UnseenQueueEvent =
+    | { readonly kind: 'update'; readonly item: InboxItem }
+    | { readonly kind: 'terminal' }
+  const unseenQueueEvents = new Map<SessionId, Map<InboxItemId, UnseenQueueEvent>>()
+  const rememberUnseen = (sessionId: SessionId, itemId: InboxItemId, event: UnseenQueueEvent): void => {
+    let events = unseenQueueEvents.get(sessionId)
+    if (events === undefined) {
+      events = new Map()
+      unseenQueueEvents.set(sessionId, events)
+    }
+    events.set(itemId, event)
+    // Only synchronous re-entrancy may deliver a mutation before its outer
+    // enqueue observer. Drop unmatched protocol-invalid observations instead
+    // of retaining process-local ids indefinitely.
+    queueMicrotask(() => {
+      const current = unseenQueueEvents.get(sessionId)
+      if (current?.get(itemId) !== event) return
+      current.delete(itemId)
+      if (current.size === 0) unseenQueueEvents.delete(sessionId)
+    })
+  }
+  const takeUnseen = (sessionId: SessionId, itemId: InboxItemId): UnseenQueueEvent | undefined => {
+    const events = unseenQueueEvents.get(sessionId)
+    const event = events?.get(itemId)
+    if (event === undefined) return undefined
+    events?.delete(itemId)
+    if (events?.size === 0) unseenQueueEvents.delete(sessionId)
+    return event
+  }
+  const publishQueue = (sessionId: SessionId): void => {
+    const items = queuedMirror.get(sessionId) ?? []
+    broadcast({
+      type: 'session/queue',
+      sessionId,
+      items: items.map(item => ({
+        id: item.id,
+        message: item.message,
+      })),
+    })
+  }
   ctx.effect(() => {
-    const retire = (agent: Agent, id: MessageId, placement?: InboxPlacement): void => {
+    const retire = (agent: Agent, item: InboxItem): boolean => {
       const entries = queuedMirror.get(agent.id)
-      if (entries === undefined) return
-      const index = entries.findIndex(entry =>
-        entry.message.id === id
-        && (placement === undefined || entry.steering === (placement === 'steering')))
-      if (index !== -1) entries.splice(index, 1)
+      if (entries === undefined) {
+        rememberUnseen(agent.id, item.id, { kind: 'terminal' })
+        return false
+      }
+      const index = entries.findIndex(entry => entry.id === item.id)
+      if (index === -1) {
+        rememberUnseen(agent.id, item.id, { kind: 'terminal' })
+        return false
+      }
+      entries.splice(index, 1)
       if (entries.length === 0) queuedMirror.delete(agent.id)
+      return true
     }
     const disposers = [
-      ctx.on('agent/inbox/enqueue', (agent: Agent, message: UserMessage, placement) => {
+      ctx.on('agent/inbox/enqueue', (agent: Agent, item: InboxItem) => {
+        if (item.placement !== 'queued') return
+        const unseen = takeUnseen(agent.id, item.id)
+        if (unseen?.kind === 'terminal') return
         let entries = queuedMirror.get(agent.id)
         if (entries === undefined) {
           entries = []
           queuedMirror.set(agent.id, entries)
         }
-        const steering = placement === 'steering'
-        entries.push({ message, steering })
-        broadcast({
-          type: 'session/queued',
-          sessionId: agent.id,
-          message,
-          steering,
-        })
+        entries.push(unseen?.kind === 'update' ? unseen.item : item)
+        publishQueue(agent.id)
       }),
-      ctx.on('agent/inbox/dequeue', (agent: Agent, message: UserMessage, placement) => {
-        retire(agent, message.id, placement)
+      ctx.on('agent/inbox/update', (agent: Agent, item: InboxItem) => {
+        const entries = queuedMirror.get(agent.id)
+        if (entries === undefined) {
+          rememberUnseen(agent.id, item.id, { kind: 'update', item })
+          return
+        }
+        const index = entries.findIndex(entry => entry.id === item.id)
+        if (index === -1) {
+          rememberUnseen(agent.id, item.id, { kind: 'update', item })
+          return
+        }
+        entries.splice(index, 1, item)
+        publishQueue(agent.id)
       }),
-      ctx.on('agent/inbox/discard', (agent: Agent, messages: UserMessage[]) => {
-        for (const message of messages) retire(agent, message.id)
+      ctx.on('agent/inbox/dequeue', (agent: Agent, item: InboxItem) => {
+        if (retire(agent, item)) publishQueue(agent.id)
+      }),
+      ctx.on('agent/inbox/discard', (agent: Agent, items: InboxItem[]) => {
+        let changed = false
+        for (const item of items) changed = retire(agent, item) || changed
+        if (changed) publishQueue(agent.id)
       }),
       ctx.on('session/disposed', (session: Session) => {
         queuedMirror.delete(session.id)
+        unseenQueueEvents.delete(session.id)
       }),
     ]
     return () => { for (const dispose of disposers) dispose() }
@@ -1268,6 +1335,75 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
         }
       },
 
+      async fork(request) {
+        const { sessionId, atSeq } = request.payload
+        const found = await agentFor(sessionId)
+        if ('error' in found) return err(request, found.error)
+        const source = found.agent.session
+        const events = source.events
+        // An in-log anchor belongs to the turn containing it and must never
+        // clip backward to an earlier completed turn. Omitted and past-end
+        // anchors retain the last-completed-turn shortcut.
+        const lastSeq = events.at(-1)?.seq ?? -1
+        const anchoredBoundary = atSeq === undefined
+          ? undefined
+          : events.find(e => e.type === 'turn/end' && e.seq >= atSeq)
+        const boundary = anchoredBoundary
+          ?? (atSeq === undefined || atSeq > lastSeq
+            ? events.findLast(e => e.type === 'turn/end')
+            : undefined)
+        if (boundary === undefined) {
+          return err(request, {
+            code: 'fork-unavailable',
+            message: atSeq !== undefined && atSeq <= lastSeq
+              ? `session "${sessionId}" has not completed the turn containing event ${String(atSeq)}`
+              : `session "${sessionId}" has no completed turn to fork from`,
+            details: { sessionId },
+          })
+        }
+        // Extend the cut through trailing out-of-band appends (session/title,
+        // injections) up to the next turn/start: they are standalone events, so
+        // the seed stays balanced, and the child inherits a title generated
+        // right after the boundary turn.
+        let cut = boundary.seq + 1
+        while (cut < events.length && events[cut]?.type !== 'turn/start') cut++
+        const childId = `session-${randomUUID()}` as SessionId
+        try {
+          await ctx.agents.create({
+            sessionId: childId,
+            seed: events.slice(0, cut),
+            meta: {
+              ...source.header.cwd === undefined ? {} : { cwd: source.header.cwd },
+              parentSession: source.id,
+              seedLength: cut,
+            },
+            agentOptions,
+            setup: installTarget,
+          })
+        } catch (error: unknown) {
+          return err(request, {
+            code: 'internal',
+            message: `failed to fork session "${sessionId}": ${String(error)}`,
+            details: {},
+          })
+        }
+        // Keep the child in the source's Workspace so the list nests it under
+        // its parent; the child is already published if the attach fails.
+        const workspace = ctx.workspace.list().find(w => w.sessionIds.includes(source.id))
+        if (workspace !== undefined) {
+          try {
+            await workspace.attachSession(childId)
+          } catch (error: unknown) {
+            return err(request, {
+              code: 'workspace-attach-failed',
+              message: `session "${childId}" was forked but could not attach to workspace "${workspace.id}": ${String(error)}`,
+              details: { sessionId: childId, workspaceId: workspace.id },
+            })
+          }
+        }
+        return ok(request, { sessionId: childId })
+      },
+
       async prompt(request) {
         const { sessionId, mode, content } = request.payload
         const found = await agentFor(sessionId)
@@ -1286,6 +1422,19 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
         return ok(request, { accepted: true as const })
       },
 
+      updateQueue(request) {
+        const { sessionId, itemId, action } = request.payload
+        const agent = ctx.agents.get(sessionId)
+        if (agent === undefined || agent.updateInbox(itemId, action) === 'not-found') {
+          return Promise.resolve(err(request, {
+            code: 'queue-item-not-found',
+            message: 'queued item is no longer pending',
+            details: { itemId },
+          }))
+        }
+        return Promise.resolve(ok(request, { accepted: true as const }))
+      },
+
       cancel(request) {
         const { sessionId } = request.payload
         const agent = ctx.agents.get(sessionId)
@@ -1681,15 +1830,15 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
         // Queue snapshot baseline (pendingQuestions precedent): frames replayed
         // in arrival order per session; a reconnecting client rebuilds its
         // queue view from these alone.
-        for (const [sessionId, entries] of queuedMirror) {
-          for (const entry of entries) {
-            queue.push(frame({
-              type: 'session/queued',
-              sessionId,
-              message: entry.message,
-              steering: entry.steering,
-            }))
-          }
+        for (const [sessionId, items] of queuedMirror) {
+          queue.push(frame({
+            type: 'session/queue',
+            sessionId,
+            items: items.map(item => ({
+              id: item.id,
+              message: item.message,
+            })),
+          }))
         }
         // Per-session open-call table for result-view pairing. Bounded by the
         // per-turn call count: entries clear on turn/end; a table miss (stream

packages/host/apiproxy/src/api/events.schema.ts

@@ -10,7 +10,9 @@ import type { HostFrame, MuxFrame } from './events.ts'
 import type { Wire } from './rpc.schema.ts'
 import { rpcErrorSchema, rpcIdSchema } from './rpc.schema.ts'
 import { approvalRequestIdSchema } from './approvals.schema.ts'
-import { contentBlockSchema, sessionEventSchema, sessionIdSchema, toolEventViewSchema } from './sessions.schema.ts'
+import {
+  contentBlockSchema, inboxItemIdSchema, sessionEventSchema, sessionIdSchema, toolEventViewSchema,
+} from './sessions.schema.ts'
 import { workspaceIdSchema, workspaceViewSchema } from './workspace.schema.ts'
 
 /** Question shape validated strictly against core dsh-user-interaction. */
@@ -21,6 +23,11 @@ export const askUserQuestionItemSchema = z.object({
   detail: z.string().optional(),
   options: z.array(z.object({ label: z.string(), description: z.string().optional() })).optional(),
   multiSelect: z.boolean().optional(),
+  // Presentation intent: a tagged union on the wire, so an unknown tag is a
+  // rejected frame rather than a silently generic render.
+  intent: z.discriminatedUnion('kind', [
+    z.object({ kind: z.literal('plan-review'), approve: z.string() }),
+  ]).optional(),
 }) satisfies z.ZodType<Wire<AskUserQuestionItem>>
 
 /** Unified message envelope carried by transient queue frames. */
@@ -42,7 +49,14 @@ export const muxFrameSchema = z.discriminatedUnion('type', [
   // and must fail loud here, not reach the composer.
   z.object({ type: z.literal('question/requested'), sessionId: sessionIdSchema, questions: z.array(askUserQuestionItemSchema).min(1) }),
   z.object({ type: z.literal('question/resolved'), sessionId: sessionIdSchema, questionRpcId: rpcIdSchema, outcome: z.union([z.literal('answered'), z.literal('cancelled')]) }),
-  z.object({ type: z.literal('session/queued'), sessionId: sessionIdSchema, message: messageSchema, steering: z.boolean() }),
+  z.object({
+    type: z.literal('session/queue'),
+    sessionId: sessionIdSchema,
+    items: z.array(z.object({
+      id: inboxItemIdSchema,
+      message: messageSchema,
+    })),
+  }),
   // value stays wide: it already passed its unit's own schema on the host,
   // and deep-validating here would import every domain's schema into the carrier.
   z.object({ type: z.literal('session/projection'), sessionId: sessionIdSchema, key: z.string().min(1), value: z.unknown(), seq: z.number().int().nonnegative() }),

packages/host/apiproxy/src/api/events.ts

@@ -9,6 +9,7 @@
 import type { AskUserQuestionItem } from '@deepseek-ai/dsh-user-interaction/types'
 import type { ApprovalOutcome, ApprovalRequestId } from '@deepseek-ai/dsh-user-approval/types'
 import type { Message } from '@deepseek-ai/dsh-llm/types'
+import type { InboxItemId } from '@deepseek-ai/dsh-agent/brand'
 import type { CallId } from '@deepseek-ai/dsh-llm/brand'
 import type { SessionEvent, SessionId } from '@deepseek-ai/dsh-session/types'
 import type { ToolCallView, ToolResultView } from '@deepseek-ai/dsh-tools/presentation'
@@ -31,6 +32,14 @@ export type ToolEventView =
   | { for: 'call'; view: ToolCallView }
   | { for: 'result'; view: ToolResultView }
 
+/** One pending queued occurrence in an authoritative queue snapshot. */
+export interface QueuedInboxItem {
+  /** Agent-owned occurrence identity used by queue mutations. */
+  id: InboxItemId
+  /** Complete pending message; it is not durable until the Agent claims it. */
+  message: Message
+}
+
 /** Streaming face of the contract: the two SSE stream openers (mux + host). */
 export interface EventsApi {
   /**
@@ -62,18 +71,13 @@ export type MuxFrame =
   | { type: 'question/requested'; sessionId: SessionId; questions: AskUserQuestionItem[] }
   | { type: 'question/resolved'; sessionId: SessionId; questionRpcId: RpcId; outcome: 'answered' | 'cancelled' }
   /**
-   * A message entered the addressed agent's inbox. A queued message is not
-   * model-visible, so there is no session event to carry it; this transient
-   * frame is the only wire signal. On stream open the
-   * host replays the current queue snapshot for every attached session (same
-   * refresh-recovery baseline as pending questions); queue clearing on cancel
-   * has no dedicated frame — clients fold it from the status flip.
-   * `steering` is the host's acceptance-time queue classification and remains
-   * authoritative in reconnect snapshots. `message.source` carries the prompt's rpcId
-   * when the message came over this wire (the client's provisional-echo
-   * reconciliation key).
+   * Complete transient queue state after every enqueue, mutation, claim, or
+   * discard. Pending work is not model-visible and therefore has no durable
+   * session event; the whole snapshot makes edit, deletion, cancel, and
+   * reconnect converge through one authoritative signal. Pending steering is
+   * outside this Web queue projection.
    */
-  | { type: 'session/queued'; sessionId: SessionId; message: Message; steering: boolean }
+  | { type: 'session/queue'; sessionId: SessionId; items: QueuedInboxItem[] }
   /**
    * One projection unit's finished value changed (session-projection RFC).
    * Live push state, never logged — replay recomputes on the host (the

packages/host/apiproxy/src/api/index.ts

@@ -29,14 +29,14 @@ export interface ApiProxy {
 // ---- Domain interfaces and payload entities ----
 export type {
   HistoryEntry, ModelCatalogFailure, ModelCatalogModel, ModelProviderGroup, ModelReasoning,
-  ModelReasoningEffort, ModelTarget, SessionModels, SessionProjectionsBlock, SessionSearchItem,
+  ModelReasoningEffort, ModelTarget, QueueAction, SessionModels, SessionProjectionsBlock, SessionSearchItem,
   SessionsApi, SessionSummary,
 } from './sessions.ts'
 export type { DirectoryEntry, DirectoryListing, HostApi } from './host.ts'
 export type { WorkspaceApi, WorkspaceId, WorkspaceView } from './workspace.ts'
 export type { CommandsApi, CommandDescriptor } from './commands.ts'
 export type { SkillsApi, SkillEntry } from './skills.ts'
-export type { EventsApi, MuxFrame, HostFrame, ToolCallView, ToolEventView, ToolResultView } from './events.ts'
+export type { EventsApi, MuxFrame, HostFrame, QueuedInboxItem, ToolCallView, ToolEventView, ToolResultView } from './events.ts'
 export type { GoalsApi, GoalId, GoalRef } from './goals.ts'
 export type { ApprovalResponsePayload } from './approvals.ts'
 export type { QuestionResponsePayload } from './questions.ts'
@@ -57,6 +57,7 @@ export type {
 // ---- Errors and ids ----
 export { RpcId, transportError } from './rpc.ts'
 export type { RpcError, RpcErrorCode, RpcErrorDetailsMap, RpcResult } from './rpc.ts'
+export type { InboxItemId } from '@deepseek-ai/dsh-agent/brand'
 
 // ---- Fixed session-search product bounds ----
 export {

packages/host/apiproxy/src/api/rpc-map.ts

@@ -25,7 +25,9 @@ export interface RpcMethodMap {
   'session.models': SessionsApi['models']
   'session.selectModel': SessionsApi['selectModel']
   'session.rename': SessionsApi['rename']
+  'session.fork': SessionsApi['fork']
   'session.prompt': SessionsApi['prompt']
+  'session.updateQueue': SessionsApi['updateQueue']
   'session.cancel': SessionsApi['cancel']
   'host.describe': HostApi['describe']
   'host.pickDirectory': HostApi['pickDirectory']

packages/host/apiproxy/src/api/rpc.schema.ts

@@ -47,9 +47,11 @@ export const rpcErrorSchema: z.ZodType<RpcError> = z.discriminatedUnion('code',
   z.object({ code: z.literal('directory-create-failed'), message: z.string(), details: z.object({ path: z.string() }) }),
   z.object({ code: z.literal('directory-picker-unavailable'), message: z.string(), details: z.object({ capability: z.string() }) }),
   z.object({ code: z.literal('agent-busy'), message: z.string(), details: z.object({ reason: z.string() }) }),
+  z.object({ code: z.literal('queue-item-not-found'), message: z.string(), details: z.object({ itemId: z.string() }) }),
   z.object({ code: z.literal('command-error'), message: z.string(), details: z.object({}) }),
   z.object({ code: z.literal('unknown-command'), message: z.string(), details: z.object({}) }),
   z.object({ code: z.literal('title-invalid'), message: z.string(), details: z.object({ sessionId: z.string() }) }),
+  z.object({ code: z.literal('fork-unavailable'), message: z.string(), details: z.object({ sessionId: z.string() }) }),
   z.object({ code: z.literal('internal'), message: z.string(), details: z.object({}) }),
 ]) as unknown as z.ZodType<RpcError>
 

packages/host/apiproxy/src/api/rpc.ts

@@ -9,6 +9,7 @@ import type { z as zCore } from 'zod'
 type ZodIssue = zCore.core.$ZodIssue
 import type { Branded } from '@deepseek-ai/dsh-brand'
 import type { SessionId } from '@deepseek-ai/dsh-session/types'
+import type { InboxItemId } from '@deepseek-ai/dsh-agent/brand'
 
 /**
  * Message correlation id: the initiator mints it on a request; a response
@@ -44,11 +45,13 @@ export interface RpcErrorDetailsMap {
   'directory-create-failed': { path: string }
   'directory-picker-unavailable': { capability: string }
   'agent-busy': { reason: string }
+  'queue-item-not-found': { itemId: InboxItemId }
   /** A known slash command reported a usage/state error; the message is the command's own text. */
   'command-error': {}
   /** A leading-/ prompt named no registered command; the message names the token. */
   'unknown-command': {}
   'title-invalid': { sessionId: SessionId }
+  'fork-unavailable': { sessionId: SessionId }
   'internal': {}
 }
 

packages/host/apiproxy/src/api/sessions.schema.ts

@@ -7,6 +7,7 @@
 
 import { z } from 'zod'
 import type { SessionEvent, SessionId } from '@deepseek-ai/dsh-session/types'
+import type { InboxItemId } from '@deepseek-ai/dsh-agent/brand'
 import type { RequestPayload, ResponseValue } from './rpc-map.ts'
 import type { Wire } from './rpc.schema.ts'
 import type {
@@ -24,6 +25,9 @@ import {
 /** SessionId: one brand cast after shape validation (the only cast point in this domain). */
 export const sessionIdSchema = z.string().min(1) as unknown as z.ZodType<SessionId>
 
+/** InboxItemId: one brand cast after non-empty string validation. */
+export const inboxItemIdSchema = z.string().min(1) as unknown as z.ZodType<InboxItemId>
+
 /**
  * WorkspaceId: the workspace domain's one brand cast. Hosted here rather
  * than in workspace.schema because session.create references it while
@@ -117,6 +121,17 @@ export const sessionRenameValueSchema = z.object({
   seq: z.number().int().nonnegative(),
 }) satisfies z.ZodType<Wire<ResponseValue<'session.rename'>>>
 
+/** session.fork request payload (atSeq anchors the completed-turn cut). */
+export const sessionForkRequestSchema = z.object({
+  sessionId: sessionIdSchema,
+  atSeq: z.number().int().nonnegative().optional(),
+}) satisfies z.ZodType<Wire<RequestPayload<'session.fork'>>>
+
+/** session.fork response value (the child session id). */
+export const sessionForkValueSchema = z.object({
+  sessionId: sessionIdSchema,
+}) satisfies z.ZodType<Wire<ResponseValue<'session.fork'>>>
+
 /** session.history request payload (beforeSeq/maxMessages page backwards from the window tail). */
 export const sessionHistoryRequestSchema = z.object({
   sessionId: sessionIdSchema,
@@ -246,6 +261,21 @@ export const sessionPromptValueSchema = z.object({
   }).optional(),
 }) satisfies z.ZodType<Wire<ResponseValue<'session.prompt'>>>
 
+/** session.updateQueue request payload. */
+export const sessionUpdateQueueRequestSchema = z.object({
+  sessionId: sessionIdSchema,
+  itemId: inboxItemIdSchema,
+  action: z.discriminatedUnion('kind', [
+    z.object({ kind: z.literal('edit'), content: z.array(contentBlockSchema) }),
+    z.object({ kind: z.literal('remove') }),
+  ]),
+}) as unknown as z.ZodType<RequestPayload<'session.updateQueue'>>
+
+/** session.updateQueue response value. */
+export const sessionUpdateQueueValueSchema = z.object({
+  accepted: z.literal(true),
+}) satisfies z.ZodType<Wire<ResponseValue<'session.updateQueue'>>>
+
 /** session.cancel request payload. */
 export const sessionCancelRequestSchema = z.object({
   sessionId: sessionIdSchema,

packages/host/apiproxy/src/api/sessions.ts

@@ -5,6 +5,7 @@
  */
 
 import type { ContentBlock } from '@deepseek-ai/dsh-llm/types'
+import type { InboxItemId } from '@deepseek-ai/dsh-agent/brand'
 import type { SessionEvent, SessionId } from '@deepseek-ai/dsh-session/types'
 // The pure-type outlet: api/ is browser-importable, and the package root's
 // cordis Context merge (via dsh-agent) must not enter client aggregates.
@@ -124,10 +125,19 @@ export interface SessionModels {
   failures: ModelCatalogFailure[]
 }
 
+/** A client-requested mutation of one still-pending queue item. */
+export type QueueAction =
+  | { kind: 'edit'; content: ContentBlock[] }
+  | { kind: 'remove' }
+
 /** Session list entry (v1 builds no index: list does readdir+stat). */
 export interface SessionSummary {
   sessionId: SessionId
-  /** Persisted file mtime. */
+  /**
+   * Last activity. Attached: the last non-`session/end-seed` event, since a
+   * pickup is not activity. Cold: the log's mtime, or `createdAt` for a backend
+   * with no per-session file (README Known Limitations covers the skew).
+   */
   updatedAt: number
   /** Status of the attached agent; always false for cold (unattached) sessions. */
   running: boolean
@@ -193,9 +203,11 @@ export interface SessionsApi {
   Promise<RpcResponse<{ sessionId: SessionId }>>
 
   /**
-   * Reads a window of history events; page boundaries align to message boundaries: one page =
-   * all raw events owned by a whole number of messages (including their chunk / tool events),
-   * never cut mid-message. The tail page (beforeSeq absent) additionally carries the in-flight
+   * Reads a window of history events; page boundaries align to append-origin message
+   * boundaries: one page = all raw events owned by a whole number of such messages (including
+   * their chunk / tool events), never cut mid-message. Model-only replacement copies consume no
+   * `maxMessages`, so a compaction's provenance stays on the page of its replacement. The tail
+   * page (beforeSeq absent) additionally carries the in-flight
    * partial — chunk events already emitted for the last unfinalized message.
    * Each entry pairs the raw SessionEvent with the host-computed view (tool events whose
    * presenter produced one, evaluated against the registry at pagination time); the client
@@ -243,9 +255,30 @@ export interface SessionsApi {
    * one — carried for future rendering; the state change is the feedback). A usage/state error is an
    * RPC error with code command-error; an unrecognized name is an RPC error with code unknown-command.
    */
+  /**
+   * Forks a new session from a completed-turn prefix of the source. `atSeq`
+   * anchors the cut: the boundary is the first `turn/end` at or after it
+   * (a message's fork button passes the message seq, so the fork includes
+   * that whole turn); a boundary past the log end, or an omitted `atSeq`,
+   * falls back to the source's last completed turn. An in-log anchor whose
+   * turn is still open fails with `fork-unavailable` instead of clipping to
+   * an earlier turn. The child inherits the source cwd, latest logged model
+   * target, workspace attachment, and `parentSessionId` lineage; the seed
+   * prefix carries the source title.
+   */
+  fork(request: RpcRequest<{ sessionId: SessionId; atSeq?: number }>):
+  Promise<RpcResponse<{ sessionId: SessionId }>>
+
+  /** Sends a message. content is core's ContentBlock[] verbatim; mode maps 1:1 — queue→send, steer→steer. */
   prompt(request: RpcRequest<{ sessionId: SessionId; mode: 'queue' | 'steer'; content: ContentBlock[] }>):
   Promise<RpcResponse<{ accepted: true; command?: { kind: 'success'; text?: string } }>>
 
+  /**
+   * Edits or removes one pending queued occurrence.
+   */
+  updateQueue(request: RpcRequest<{ sessionId: SessionId; itemId: InboxItemId; action: QueueAction }>):
+  Promise<RpcResponse<{ accepted: true }>>
+
   /** Stops: clears both FIFOs + aborts the current step (1:1 with agent.cancel). */
   cancel(request: RpcRequest<{ sessionId: SessionId }>): Promise<RpcResponse<{ accepted: true }>>
 

packages/host/apiproxy/src/fetch/client.ts

@@ -20,6 +20,7 @@ import {
 import {
   sessionCancelValueSchema,
   sessionCreateValueSchema,
+  sessionForkValueSchema,
   sessionHistoryValueSchema,
   sessionListValueSchema,
   sessionModelsValueSchema,
@@ -27,6 +28,7 @@ import {
   sessionRenameValueSchema,
   sessionSearchValueSchema,
   sessionSelectModelValueSchema,
+  sessionUpdateQueueValueSchema,
 } from '../api/sessions.schema.ts'
 import {
   workspaceCreateValueSchema,
@@ -70,7 +72,9 @@ export interface IApiClient {
     models(payload: RequestPayload<'session.models'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'session.models'>>>
     selectModel(payload: RequestPayload<'session.selectModel'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'session.selectModel'>>>
     rename(payload: RequestPayload<'session.rename'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'session.rename'>>>
+    fork(payload: RequestPayload<'session.fork'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'session.fork'>>>
     prompt(payload: RequestPayload<'session.prompt'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'session.prompt'>>>
+    updateQueue(payload: RequestPayload<'session.updateQueue'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'session.updateQueue'>>>
     cancel(payload: RequestPayload<'session.cancel'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'session.cancel'>>>
   }
   host: {
@@ -122,7 +126,9 @@ const UNARY_VALUE_SCHEMAS: { [K in keyof RpcMethodMap]: z.ZodType<Wire<ResponseV
   'session.models': sessionModelsValueSchema,
   'session.selectModel': sessionSelectModelValueSchema,
   'session.rename': sessionRenameValueSchema,
+  'session.fork': sessionForkValueSchema,
   'session.prompt': sessionPromptValueSchema,
+  'session.updateQueue': sessionUpdateQueueValueSchema,
   'session.cancel': sessionCancelValueSchema,
   'host.describe': hostDescribeValueSchema,
   'host.pickDirectory': hostPickDirectoryValueSchema,
@@ -335,7 +341,9 @@ export abstract class AbstractApiClient implements IApiClient {
     models: (payload, signal) => this.callUnary('session.models', payload, signal),
     selectModel: (payload, signal) => this.callUnary('session.selectModel', payload, signal),
     rename: (payload, signal) => this.callUnary('session.rename', payload, signal),
+    fork: (payload, signal) => this.callUnary('session.fork', payload, signal),
     prompt: (payload, signal) => this.callUnary('session.prompt', payload, signal),
+    updateQueue: (payload, signal) => this.callUnary('session.updateQueue', payload, signal),
     cancel: (payload, signal) => this.callUnary('session.cancel', payload, signal),
   }
 

packages/host/apiproxy/src/fetch/handler.ts

@@ -17,6 +17,7 @@ import { clientRequestSchema, clientResponseSchema } from '../api/rpc.schema.ts'
 import {
   sessionCancelRequestSchema,
   sessionCreateRequestSchema,
+  sessionForkRequestSchema,
   sessionHistoryRequestSchema,
   sessionListRequestSchema,
   sessionModelsRequestSchema,
@@ -24,6 +25,7 @@ import {
   sessionRenameRequestSchema,
   sessionSearchRequestSchema,
   sessionSelectModelRequestSchema,
+  sessionUpdateQueueRequestSchema,
 } from '../api/sessions.schema.ts'
 import {
   hostCreateDirectoryRequestSchema, hostDescribeRequestSchema,
@@ -73,7 +75,9 @@ const UNARY_ROUTES: UnaryRoutes = {
   'session.models': { schema: sessionModelsRequestSchema, invoke: (api, r) => api.sessions.models(r) },
   'session.selectModel': { schema: sessionSelectModelRequestSchema, invoke: (api, r) => api.sessions.selectModel(r) },
   'session.rename': { schema: sessionRenameRequestSchema, invoke: (api, r) => api.sessions.rename(r) },
+  'session.fork': { schema: sessionForkRequestSchema, invoke: (api, r) => api.sessions.fork(r) },
   'session.prompt': { schema: sessionPromptRequestSchema, invoke: (api, r) => api.sessions.prompt(r) },
+  'session.updateQueue': { schema: sessionUpdateQueueRequestSchema, invoke: (api, r) => api.sessions.updateQueue(r) },
   'session.cancel': { schema: sessionCancelRequestSchema, invoke: (api, r) => api.sessions.cancel(r) },
   'host.describe': { schema: hostDescribeRequestSchema, invoke: (api, r) => api.host.describe(r) },
   'host.pickDirectory': { schema: hostPickDirectoryRequestSchema, invoke: (api, r, signal) => api.host.pickDirectory(r, signal) },