fix(workspace): unify pin IDs and preserve complete session order

packages/api/workspace-controller/README.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write packages/api/workspace-controller/README.md
-README.md: ccf07bfb61ad005d516928ad27145148a62ddf19
-README.zh.md: b96f49e92696cef2475458f4b51c764063aa32f9
+README.md: 46556b0105bb5186cf27b56faee4127b358eac9b
+README.zh.md: 9d210c10486a71772cf6c0a10480b734fa992441

packages/api/workspace-controller/README.md

@@ -22,9 +22,9 @@ English | [中文](README.zh.md)
 <a id="use-this-package"></a>
 ## Use this package
 
-The Host controller serializes mutations whose correctness depends on current registry state and throws `RemoteError` with a stable `workspace/*` or `directory-picker/*` code for expected failures. Its `follow()` stream synchronously attaches to durable Workspace changes, emits one complete baseline first, then emits ordered `upsert`, `remove`, `order`, and `archived` increments. A reconnect starts another generation with a replacement baseline, so consumers do not depend on receiving every increment while disconnected.
+The Host controller serializes mutations whose correctness depends on current registry state and throws `RemoteError` with a stable error code for expected failures. Its `follow()` stream synchronously attaches to durable Workspace changes, emits one complete baseline first, then emits ordered `upsert`, `remove`, `order`, `archived`, and `pinned` increments. Archive and pin sets are Session id arrays, with the most recently pinned id first in the pin array. A reconnect starts another generation with a replacement baseline, so consumers do not depend on receiving every increment while disconnected.
 
-The Client entry provides `ClientWorkspaceModel` and `createWorkspaceStateStream()`. The model owns Workspace rows, registry order, archived Session ids, unary mutation echoes, and stream/unary race resolution. A newer Host row wins by `updatedAt`; a committed stream order outranks an older unary response; a removed Workspace id cannot be resurrected by delayed data. The package exposes framework-neutral snapshots and subscriptions, leaving navigation policy and React hooks to the UI owner.
+The Client entry provides `ClientWorkspaceModel` and `createWorkspaceStateStream()`. The model owns Workspace rows, registry order, archived and pinned Session identities, unary mutation echoes, and stream/unary race resolution. A newer Host row wins by `updatedAt`; a committed stream order outranks an older unary response; a removed Workspace id cannot be resurrected by delayed data. Pin snapshots change only when their identities or order change. The package exposes framework-neutral snapshots and subscriptions, leaving navigation policy and React hooks to the UI owner.
 
 -----
 

packages/api/workspace-controller/README.zh.md

@@ -22,9 +22,9 @@ kind: "package-reference"
 <a id="use-this-package"></a>
 ## 使用本包
 
-Host 控制器会串行执行正确性取决于当前注册表状态的变更，并为预期失败抛出带有稳定 `workspace/*` 或 `directory-picker/*` 错误码的 `RemoteError`。它的 `follow()` 流会同步订阅持久 Workspace 变更，先发出一份完整 baseline，再按顺序发出 `upsert`、`remove`、`order` 和 `archived` 增量。重连会以替换 baseline 开始新一代，因此消费方不依赖收到断线期间的每个增量。
+Host 控制器会串行执行正确性取决于当前注册表状态的变更，并为预期失败抛出带有稳定错误码的 `RemoteError`。它的 `follow()` 流会同步订阅持久 Workspace 变更，先发出一份完整 baseline，再按顺序发出 `upsert`、`remove`、`order`、`archived` 和 `pinned` 增量。归档与置顶集合都是会话 id 数组，置顶数组把最近置顶的 id 放在前面。重连会以替换 baseline 开始新一代，因此消费方不依赖收到断线期间的每个增量。
 
-Client 入口提供 `ClientWorkspaceModel` 和 `createWorkspaceStateStream()`。该模型拥有 Workspace 行、registry 顺序、已归档 Session id、一元变更回显，以及流与一元调用的竞态处理。较新的 Host 行按 `updatedAt` 获胜；已提交的流顺序优先于较旧的一元响应；已经移除的 Workspace id 不会被延迟数据复活。该包公开与框架无关的快照和订阅，把导航策略与 React 钩子留给 UI owner。
+Client 入口提供 `ClientWorkspaceModel` 和 `createWorkspaceStateStream()`。该模型拥有 Workspace 行、registry 顺序、归档与置顶会话身份、一元变更回显，以及流与一元调用的竞态处理。较新的 Host 行按 `updatedAt` 获胜；已提交的流顺序优先于较旧的一元响应；已经移除的 Workspace id 不会被延迟数据复活。置顶快照仅在会话身份或顺序变化时更新。该包公开与框架无关的快照和订阅，把导航策略与 React 钩子留给 UI owner。
 
 -----
 

packages/api/workspace-controller/src/client/index.ts

@@ -17,7 +17,7 @@ export type {
 } from './model.ts'
 export { WorkspaceController, WorkspaceCreateError } from './service.ts'
 export type { IWorkspaces, WorkspaceSource } from './service.ts'
-export type { WorkspaceId, WorkspacePinnedSession, WorkspaceView } from '../types.ts'
+export type { WorkspaceId, WorkspaceView } from '../types.ts'
 
 type WorkspaceBaselineFrame = Extract<WorkspaceFollowFrame, { type: 'baseline' }>
 
@@ -108,7 +108,7 @@ function acceptIncrement(accept: WorkspaceFollowSink, frame: WorkspaceFollowIncr
       accept.replaceArchived(frame.archivedSessionIds)
       return
     case 'pinned':
-      accept.replacePinned(frame.pinnedSessions)
+      accept.replacePinned(frame.pinnedSessionIds)
       return
     /* v8 ignore next -- the generated Remote codec validates this closed union */
     default:

packages/api/workspace-controller/src/client/model.ts

@@ -34,7 +34,7 @@ export interface WorkspaceSnapshot {
   /** Complete registry-global archive set in Host order. */
   readonly archivedSessionIds: WorkspaceArchiveValue['archivedSessionIds']
   /** Complete registry-global pin set, most recently pinned first. */
-  readonly pinnedSessions: WorkspacePinValue['pinnedSessions']
+  readonly pinnedSessionIds: WorkspacePinValue['pinnedSessionIds']
   readonly state: 'idle' | 'loading' | 'error'
   readonly phase: WorkspaceListPhase
   readonly error: RemoteFailure | null
@@ -53,7 +53,7 @@ export interface WorkspaceFollowSink {
   /** Replace the complete archived Session set. */
   replaceArchived(sessionIds: WorkspaceArchiveValue['archivedSessionIds']): void
   /** Replace the complete pinned Session set. */
-  replacePinned(pinnedSessions: WorkspacePinValue['pinnedSessions']): void
+  replacePinned(pinnedSessionIds: WorkspacePinValue['pinnedSessionIds']): void
 }
 
 /**
@@ -62,7 +62,7 @@ export interface WorkspaceFollowSink {
 export class ClientWorkspaceModel implements WorkspaceFollowSink {
   private items: readonly WorkspaceView[] = []
   private archivedSessionIds: WorkspaceArchiveValue['archivedSessionIds'] = []
-  private pinnedSessions: WorkspacePinValue['pinnedSessions'] = []
+  private pinnedSessionIds: WorkspacePinValue['pinnedSessionIds'] = []
   private state: WorkspaceSnapshot['state'] = 'loading'
   private phase: WorkspaceListPhase = 'pending'
   private error: RemoteFailure | null = null
@@ -185,7 +185,7 @@ export class ClientWorkspaceModel implements WorkspaceFollowSink {
       this.installArchived(result.value.archivedSessionIds)
       // The Host drops an archived session's pin in the same durable write;
       // mirror that locally so no frame shows the row both archived and pinned.
-      this.installPinned(this.pinnedSessions.filter(entry => entry.sessionId !== sessionId))
+      this.installPinned(this.pinnedSessionIds.filter(id => id !== sessionId))
     }
     return result
   }
@@ -219,7 +219,7 @@ export class ClientWorkspaceModel implements WorkspaceFollowSink {
     const requestSeq = ++this.pinRequestSeq
     const result = await this.remote.pinSession({ sessionId })
     if (result.ok && requestSeq === this.pinRequestSeq) {
-      this.installPinned(result.value.pinnedSessions)
+      this.installPinned(result.value.pinnedSessionIds)
     }
     return result
   }
@@ -236,7 +236,7 @@ export class ClientWorkspaceModel implements WorkspaceFollowSink {
     const requestSeq = ++this.pinRequestSeq
     const result = await this.remote.unpinSession({ sessionId })
     if (result.ok && requestSeq === this.pinRequestSeq) {
-      this.installPinned(result.value.pinnedSessions)
+      this.installPinned(result.value.pinnedSessionIds)
     }
     return result
   }
@@ -251,7 +251,7 @@ export class ClientWorkspaceModel implements WorkspaceFollowSink {
     this.pinRequestSeq++
     this.installViews(baseline.items)
     this.installArchived(baseline.archivedSessionIds)
-    this.installPinned(baseline.pinnedSessions)
+    this.installPinned(baseline.pinnedSessionIds)
     this.state = 'idle'
     this.phase = 'ready'
     this.error = null
@@ -285,11 +285,11 @@ export class ClientWorkspaceModel implements WorkspaceFollowSink {
 
   /**
    * Replace the pinned Session set from the current follow generation.
-   * @param pinnedSessions - complete Host-confirmed pin set, most recently pinned first.
+   * @param pinnedSessionIds - complete Host-confirmed pin set, most recently pinned first.
    */
-  replacePinned(pinnedSessions: WorkspacePinValue['pinnedSessions']): void {
+  replacePinned(pinnedSessionIds: WorkspacePinValue['pinnedSessionIds']): void {
     this.pinRequestSeq++
-    this.installPinned(pinnedSessions)
+    this.installPinned(pinnedSessionIds)
   }
 
   /** Keep the last complete projection visible while a lost carrier reconnects. */
@@ -333,7 +333,7 @@ export class ClientWorkspaceModel implements WorkspaceFollowSink {
     return {
       items: this.items,
       archivedSessionIds: this.archivedSessionIds,
-      pinnedSessions: this.pinnedSessions,
+      pinnedSessionIds: this.pinnedSessionIds,
       state: this.state,
       phase: this.phase,
       error: this.error,
@@ -347,11 +347,10 @@ export class ClientWorkspaceModel implements WorkspaceFollowSink {
     this.invalidate()
   }
 
-  private installPinned(pinnedSessions: WorkspacePinValue['pinnedSessions']): void {
-    if (pinnedSessions.length === this.pinnedSessions.length
-      && pinnedSessions.every((entry, index) => entry.sessionId === this.pinnedSessions[index]?.sessionId
-        && entry.pinnedAt === this.pinnedSessions[index]?.pinnedAt)) return
-    this.pinnedSessions = [...pinnedSessions]
+  private installPinned(pinnedSessionIds: WorkspacePinValue['pinnedSessionIds']): void {
+    if (pinnedSessionIds.length === this.pinnedSessionIds.length
+      && pinnedSessionIds.every((id, index) => id === this.pinnedSessionIds[index])) return
+    this.pinnedSessionIds = [...pinnedSessionIds]
     this.invalidate()
   }
 

packages/api/workspace-controller/src/client/service.ts

@@ -73,7 +73,7 @@ export interface IWorkspaces {
    */
   pinSession(sessionId: SessionId): Promise<void>
   /**
-   * Unpin a Session back to its natural list position.
+   * Remove a Session's pin without changing its saved Session order.
    * @param sessionId - Session to unpin.
    */
   unpinSession(sessionId: SessionId): Promise<void>

packages/api/workspace-controller/src/commands.ts

@@ -10,7 +10,7 @@ import {
   WorkspaceUnknownSessionError,
 } from '@deepseek-ai/dsh-workspace'
 import { RemoteError, remoteErrorOf } from '@deepseek-ai/dsh-typert-protocol'
-import { pinnedSessionViews, workspaceView } from './feed.ts'
+import { workspaceView } from './feed.ts'
 import type {
   WorkspaceArchiveSessionRequest,
   WorkspaceArchiveValue,
@@ -194,7 +194,7 @@ export class WorkspaceCommands {
       }
       throw error
     }
-    return { pinnedSessions: pinnedSessionViews(this.ctx.workspaceRegistry.pinnedSessions) }
+    return { pinnedSessionIds: [...this.ctx.workspaceRegistry.pinnedSessionIds] }
   }
 
   /**
@@ -206,7 +206,7 @@ export class WorkspaceCommands {
    */
   async unpinSession(request: WorkspaceUnpinSessionRequest): Promise<WorkspacePinValue> {
     await this.ctx.workspaceRegistry.unpinSession(request.sessionId)
-    return { pinnedSessions: pinnedSessionViews(this.ctx.workspaceRegistry.pinnedSessions) }
+    return { pinnedSessionIds: [...this.ctx.workspaceRegistry.pinnedSessionIds] }
   }
 
   private requireWorkspace(workspaceId: WorkspaceId): Workspace {

packages/api/workspace-controller/src/feed.ts

@@ -3,7 +3,7 @@
 import type { Context } from '@deepseek-ai/cordis'
 import { Deque } from '@deepseek-ai/dsh-deque'
 import type { DomainChanged } from '@deepseek-ai/dsh-storage-domain'
-import type { PinnedSession, Workspace, WorkspaceRecord } from '@deepseek-ai/dsh-workspace'
+import type { Workspace, WorkspaceRecord } from '@deepseek-ai/dsh-workspace'
 import {
   workspaceDomainState,
   workspaceRecord,
@@ -12,7 +12,6 @@ import {
 import type {
   WorkspaceBaseline,
   WorkspaceFollowFrame,
-  WorkspacePinnedSession,
   WorkspaceView,
 } from './types.ts'
 
@@ -44,19 +43,6 @@ function changedWorkspaceView(workspaceId: string, value: unknown): WorkspaceVie
   }
 }
 
-/**
- * Project registry pin entries into their Remote values.
- * @param entries - authoritative registry pin entries.
- * @returns detached pin projections for Remote consumers.
- */
-export function pinnedSessionViews(entries: readonly PinnedSession[]): WorkspacePinnedSession[] {
-  return entries.map(entry => ({ sessionId: entry.id, pinnedAt: entry.pinnedAt }))
-}
-
-/** One comparable key per pin entry; pinnedAt participates so a re-pin at a new instant publishes. */
-const pinKeys = (entries: readonly PinnedSession[]): string[] =>
-  entries.map(entry => `${entry.id}@${entry.pinnedAt}`)
-
 /** Owns Workspace domain observation and all active follow generations. */
 export class WorkspaceFeed {
   private readonly followers = new Set<WorkspaceFollower>()
@@ -71,7 +57,7 @@ export class WorkspaceFeed {
     this.knownIds = new Set(baseline.map(workspace => String(workspace.id)))
     this.order = baseline.map(workspace => String(workspace.id))
     this.archived = ctx.workspaceRegistry.archivedSessionIds.map(String)
-    this.pinned = pinKeys(ctx.workspaceRegistry.pinnedSessions)
+    this.pinned = ctx.workspaceRegistry.pinnedSessionIds.map(String)
     ctx.on('domain/changed', (change: DomainChanged) => { this.changed(change) })
     ctx.effect(() => () => {
       for (const follower of this.followers) follower.close()
@@ -87,7 +73,7 @@ export class WorkspaceFeed {
     return {
       items: this.ctx.workspaceRegistry.list().map(workspaceView),
       archivedSessionIds: [...this.ctx.workspaceRegistry.archivedSessionIds],
-      pinnedSessions: pinnedSessionViews(this.ctx.workspaceRegistry.pinnedSessions),
+      pinnedSessionIds: [...this.ctx.workspaceRegistry.pinnedSessionIds],
     }
   }
 
@@ -132,10 +118,10 @@ export class WorkspaceFeed {
         this.archived = nextArchived
         this.publish({ type: 'archived', archivedSessionIds: [...state.archivedSessionIds] })
       }
-      const nextPinned = pinKeys(state.pinnedSessions)
+      const nextPinned = state.pinnedSessionIds.map(String)
       if (!sameStrings(this.pinned, nextPinned)) {
         this.pinned = nextPinned
-        this.publish({ type: 'pinned', pinnedSessions: pinnedSessionViews(state.pinnedSessions) })
+        this.publish({ type: 'pinned', pinnedSessionIds: [...state.pinnedSessionIds] })
       }
       return
     }

packages/api/workspace-controller/src/index.ts

@@ -134,7 +134,7 @@ export class WorkspaceController extends TypertRemoteService {
   }
 
   /**
-   * Return one pinned Session to its natural list position.
+   * Remove one Session's pin without changing its saved Session order.
    * @param request - Session identity to unpin.
    * @returns the complete resulting pin set, most recently pinned first.
    */

packages/api/workspace-controller/src/types.ts

@@ -119,20 +119,14 @@ export interface WorkspacePinSessionRequest {
   readonly sessionId: SessionId
 }
 
-/** Session requested for unpinning back to its natural list position. */
+/** Session requested for removal from the pin set. */
 export interface WorkspaceUnpinSessionRequest {
   readonly sessionId: SessionId
 }
 
-/** One pinned Session entry: the Session and the epoch-millisecond instant it was pinned at. */
-export interface WorkspacePinnedSession {
-  readonly sessionId: SessionId
-  readonly pinnedAt: number
-}
-
 /** Complete pinned Session set after a mutation, most recently pinned first. */
 export interface WorkspacePinValue {
-  readonly pinnedSessions: readonly WorkspacePinnedSession[]
+  readonly pinnedSessionIds: readonly SessionId[]
 }
 
 /** Complete reconnect baseline for Workspace browser state. */
@@ -140,7 +134,7 @@ export interface WorkspaceBaseline {
   readonly items: readonly WorkspaceView[]
   readonly archivedSessionIds: readonly SessionId[]
   /** Registry-global pin set, most recently pinned first. */
-  readonly pinnedSessions: readonly WorkspacePinnedSession[]
+  readonly pinnedSessionIds: readonly SessionId[]
 }
 
 /** One ordered Workspace change after a generation's baseline. */
@@ -149,7 +143,7 @@ export type WorkspaceFollowIncrement =
   | { readonly type: 'remove'; readonly workspaceId: WorkspaceId }
   | { readonly type: 'order'; readonly workspaceIds: readonly WorkspaceId[] }
   | { readonly type: 'archived'; readonly archivedSessionIds: readonly SessionId[] }
-  | { readonly type: 'pinned'; readonly pinnedSessions: readonly WorkspacePinnedSession[] }
+  | { readonly type: 'pinned'; readonly pinnedSessionIds: readonly SessionId[] }
 
 /** Workspace state stream; every generation starts with exactly one baseline. */
 export type WorkspaceFollowFrame =

packages/api/workspace-controller/tests/model.client.spec.ts

@@ -20,7 +20,6 @@ import type {
   WorkspaceUnpinSessionRequest,
   WorkspaceValue,
   WorkspaceId,
-  WorkspacePinnedSession,
   WorkspaceView,
 } from '../src/types.ts'
 import { RemoteError, type RemoteFailure, type RemoteResult } from '@deepseek-ai/dsh-typert-protocol'
@@ -28,9 +27,6 @@ import type { SessionId } from '@deepseek-ai/dsh-session/types'
 
 const sid = (id: string): SessionId => id as SessionId
 const wid = (id: string): WorkspaceId => id as WorkspaceId
-const pin = (id: string, pinnedAt = 1): WorkspacePinnedSession => ({ sessionId: sid(id), pinnedAt })
-const pinnedIds = (entries: readonly WorkspacePinnedSession[]): string[] =>
-  entries.map(entry => String(entry.sessionId))
 
 function workspace(
   id: string,
@@ -99,11 +95,11 @@ class FakeWorkspaceRemote implements WorkspaceRemote {
   onPinSession: (
     request: WorkspacePinSessionRequest,
   ) => Promise<RemoteResult<WorkspacePinValue>> = request =>
-    Promise.resolve(remoteOk({ pinnedSessions: [{ sessionId: request.sessionId, pinnedAt: 1 }] }))
+    Promise.resolve(remoteOk({ pinnedSessionIds: [request.sessionId] }))
   onUnpinSession: (
     _request: WorkspaceUnpinSessionRequest,
   ) => Promise<RemoteResult<WorkspacePinValue>> = () =>
-    Promise.resolve(remoteOk({ pinnedSessions: [] }))
+    Promise.resolve(remoteOk({ pinnedSessionIds: [] }))
 
   create(request: WorkspaceCreateRequest): Promise<RemoteResult<WorkspaceCreateValue>> {
     this.record('create', request)
@@ -165,9 +161,9 @@ function baseline(
   model: ClientWorkspaceModel,
   items: readonly WorkspaceView[] = [],
   archivedSessionIds: readonly SessionId[] = [],
-  pinnedSessions: readonly WorkspacePinnedSession[] = [],
+  pinnedSessionIds: readonly SessionId[] = [],
 ): void {
-  model.replaceBaseline({ items, archivedSessionIds, pinnedSessions })
+  model.replaceBaseline({ items, archivedSessionIds, pinnedSessionIds })
 }
 
 describe('ClientWorkspaceModel', () => {
@@ -422,38 +418,36 @@ describe('ClientWorkspaceModel', () => {
   it('applies pin mutation echoes and leaves failed results unchanged', async () => {
     const remote = new FakeWorkspaceRemote()
     const model = modelFor(remote)
-    baseline(model, [], [], [pin('kept')])
+    baseline(model, [], [], [sid('kept')])
 
     remote.onPinSession = () => Promise.resolve(workspaceError(
       new RemoteError('session/not-found', 'missing', { sessionId: sid('missing') }),
     ))
     await expect(model.pinSession(sid('missing'))).resolves.toMatchObject({ ok: false })
-    expect(pinnedIds(model.getSnapshot().pinnedSessions)).toEqual(['kept'])
+    expect(model.getSnapshot().pinnedSessionIds).toEqual(['kept'])
     remote.onPinSession = request => Promise.resolve(remoteOk({
-      pinnedSessions: [{ sessionId: request.sessionId, pinnedAt: 2 }, pin('kept')],
+      pinnedSessionIds: [request.sessionId, sid('kept')],
     }))
     await expect(model.pinSession(sid('fresh'))).resolves.toMatchObject({ ok: true })
-    expect(pinnedIds(model.getSnapshot().pinnedSessions)).toEqual(['fresh', 'kept'])
+    expect(model.getSnapshot().pinnedSessionIds).toEqual(['fresh', 'kept'])
     expect(remote.calls).toContainEqual({ method: 'pinSession', request: { sessionId: 'fresh' } })
 
     remote.onUnpinSession = () => Promise.resolve(workspaceError(
       new RemoteError('gateway/internal', 'wire down', {}),
     ))
     await expect(model.unpinSession(sid('fresh'))).resolves.toMatchObject({ ok: false })
-    expect(pinnedIds(model.getSnapshot().pinnedSessions)).toEqual(['fresh', 'kept'])
-    remote.onUnpinSession = () => Promise.resolve(remoteOk({ pinnedSessions: [pin('kept')] }))
+    expect(model.getSnapshot().pinnedSessionIds).toEqual(['fresh', 'kept'])
+    remote.onUnpinSession = () => Promise.resolve(remoteOk({ pinnedSessionIds: [sid('kept')] }))
     await expect(model.unpinSession(sid('fresh'))).resolves.toMatchObject({ ok: true })
-    expect(pinnedIds(model.getSnapshot().pinnedSessions)).toEqual(['kept'])
+    expect(model.getSnapshot().pinnedSessionIds).toEqual(['kept'])
     expect(remote.calls).toContainEqual({ method: 'unpinSession', request: { sessionId: 'fresh' } })
 
-    // A pushed set identical to the local one publishes no new snapshot; the
-    // same member re-pinned at a new instant does.
     const before = model.getSnapshot()
-    model.replacePinned([pin('kept')])
+    model.replacePinned([sid('kept')])
     expect(model.getSnapshot()).toBe(before)
-    model.replacePinned([pin('kept', 9)])
+    model.replacePinned([sid('other')])
     expect(model.getSnapshot()).not.toBe(before)
-    expect(model.getSnapshot().pinnedSessions).toEqual([pin('kept', 9)])
+    expect(model.getSnapshot().pinnedSessionIds).toEqual([sid('other')])
   })
 
   it('keeps the latest pin reply when overlapping requests settle out of order', async () => {
@@ -466,36 +460,36 @@ describe('ClientWorkspaceModel', () => {
 
     const first = model.pinSession(sid('first'))
     const second = model.pinSession(sid('second'))
-    secondGate.resolve(remoteOk({ pinnedSessions: [pin('second', 2), pin('first')] }))
+    secondGate.resolve(remoteOk({ pinnedSessionIds: [sid('second'), sid('first')] }))
     await expect(second).resolves.toMatchObject({ ok: true })
-    expect(pinnedIds(model.getSnapshot().pinnedSessions)).toEqual(['second', 'first'])
-    firstGate.resolve(remoteOk({ pinnedSessions: [pin('first')] }))
+    expect(model.getSnapshot().pinnedSessionIds).toEqual(['second', 'first'])
+    firstGate.resolve(remoteOk({ pinnedSessionIds: [sid('first')] }))
     await expect(first).resolves.toMatchObject({ ok: true })
-    expect(pinnedIds(model.getSnapshot().pinnedSessions)).toEqual(['second', 'first'])
+    expect(model.getSnapshot().pinnedSessionIds).toEqual(['second', 'first'])
   })
 
   it('keeps a pushed pin set when an unpin reply lands later', async () => {
     const remote = new FakeWorkspaceRemote()
     const model = modelFor(remote)
-    baseline(model, [], [], [pin('first')])
+    baseline(model, [], [], [sid('first')])
     const gate = deferred<RemoteResult<WorkspacePinValue>>()
     remote.onUnpinSession = () => gate.promise
 
     const pending = model.unpinSession(sid('first'))
-    model.replacePinned([pin('first'), pin('second', 2)])
-    gate.resolve(remoteOk({ pinnedSessions: [] }))
+    model.replacePinned([sid('first'), sid('second')])
+    gate.resolve(remoteOk({ pinnedSessionIds: [] }))
     await expect(pending).resolves.toMatchObject({ ok: true })
-    expect(pinnedIds(model.getSnapshot().pinnedSessions)).toEqual(['first', 'second'])
+    expect(model.getSnapshot().pinnedSessionIds).toEqual(['first', 'second'])
   })
 
   it('mirrors the Host pin drop locally when an archive echo lands', async () => {
     const remote = new FakeWorkspaceRemote()
     const model = modelFor(remote)
-    baseline(model, [], [], [pin('pinned'), pin('kept')])
+    baseline(model, [], [], [sid('pinned'), sid('kept')])
 
     await expect(model.archiveSession(sid('pinned'))).resolves.toMatchObject({ ok: true })
     expect(model.getSnapshot().archivedSessionIds).toEqual(['pinned'])
-    expect(pinnedIds(model.getSnapshot().pinnedSessions)).toEqual(['kept'])
+    expect(model.getSnapshot().pinnedSessionIds).toEqual(['kept'])
   })
 
   it('keeps the newest row and places Workspaces missing from partial orders last', async () => {

packages/api/workspace-controller/tests/remote/workspace.client.ts

@@ -69,7 +69,7 @@ export function workspace(id: string, overrides: Partial<WorkspaceView> = {}): W
 export function baseline(...ids: readonly string[]): WorkspaceBaselineFrame {
   return {
     type: 'baseline',
-    value: { items: ids.map(id => workspace(id)), archivedSessionIds: [], pinnedSessions: [] },
+    value: { items: ids.map(id => workspace(id)), archivedSessionIds: [], pinnedSessionIds: [] },
   }
 }
 
@@ -104,7 +104,7 @@ export const workspaceWorld: RemoteTable = {
     }),
     'workspace/archiveSession': (request: WorkspaceArchiveSessionRequest): RemoteResult<WorkspaceArchiveValue> => ok({ archivedSessionIds: [request.sessionId] }),
     'workspace/unarchiveSession': (_request: WorkspaceUnarchiveSessionRequest): RemoteResult<WorkspaceArchiveValue> => ok({ archivedSessionIds: [] }),
-    'workspace/pinSession': (request: WorkspacePinSessionRequest): RemoteResult<WorkspacePinValue> => ok({ pinnedSessions: [{ sessionId: request.sessionId, pinnedAt: 1 }] }),
-    'workspace/unpinSession': (_request: WorkspaceUnpinSessionRequest): RemoteResult<WorkspacePinValue> => ok({ pinnedSessions: [] }),
+    'workspace/pinSession': (request: WorkspacePinSessionRequest): RemoteResult<WorkspacePinValue> => ok({ pinnedSessionIds: [request.sessionId] }),
+    'workspace/unpinSession': (_request: WorkspaceUnpinSessionRequest): RemoteResult<WorkspacePinValue> => ok({ pinnedSessionIds: [] }),
   },
 }

packages/api/workspace-controller/tests/transport.client.spec.ts

@@ -154,7 +154,7 @@ describe('Workspace state stream', () => {
       { type: 'remove', workspaceId: view.workspaceId },
       { type: 'order', workspaceIds: [view.workspaceId] },
       { type: 'archived', archivedSessionIds: [sid('session-one')] },
-      { type: 'pinned', pinnedSessions: [{ sessionId: sid('session-two'), pinnedAt: 1 }] },
+      { type: 'pinned', pinnedSessionIds: [sid('session-two')] },
     ]
     mock.stream(FOLLOW, openStream([opening, ...increments]))
     const replaceBaseline = vi.fn<WorkspaceFollowSink['replaceBaseline']>()
@@ -177,7 +177,7 @@ describe('Workspace state stream', () => {
     expect(removeView).toHaveBeenCalledWith(view.workspaceId)
     expect(replaceOrder).toHaveBeenCalledWith([view.workspaceId])
     expect(replaceArchived).toHaveBeenCalledWith(['session-one'])
-    expect(replacePinned).toHaveBeenCalledWith([{ sessionId: 'session-two', pinnedAt: 1 }])
+    expect(replacePinned).toHaveBeenCalledWith(['session-two'])
     await stream.dispose()
     expect(streamStates(mock)).toEqual(['cancelled'])
   })
@@ -313,7 +313,7 @@ describe('WorkspaceController', () => {
   it('publishes the model source and exposes successful Workspace commands', async ({ mock, start }) => {
     const { remote, client } = await gatewayClient(mock, start)
     const model = new ClientWorkspaceModel(remote.workspace)
-    model.replaceBaseline({ items: [workspace('one')], archivedSessionIds: [], pinnedSessions: [] })
+    model.replaceBaseline({ items: [workspace('one')], archivedSessionIds: [], pinnedSessionIds: [] })
     const controller = new WorkspaceController(client.ctx, model)
 
     expect(controller.list).toBe(model)

packages/api/workspace-controller/tests/workspace-controller.host.spec.ts

@@ -251,7 +251,7 @@ describe('WorkspaceController commands', () => {
     })
 
     await expect(controller.pinSession({ sessionId: session.id }))
-      .resolves.toEqual({ pinnedSessions: [{ sessionId: session.id, pinnedAt: expect.any(Number) }] })
+      .resolves.toEqual({ pinnedSessionIds: [session.id] })
     await expect(controller.pinSession({ sessionId: SessionId('unknown') }))
       .rejects.toMatchObject({ code: 'session/not-found' })
 
@@ -264,10 +264,10 @@ describe('WorkspaceController commands', () => {
       .rejects.toMatchObject({ code: 'gateway/bad-request' })
 
     await expect(controller.unpinSession({ sessionId: session.id }))
-      .resolves.toEqual({ pinnedSessions: [] })
+      .resolves.toEqual({ pinnedSessionIds: [] })
     // Unpin is idempotent: an id that is not pinned is not an error.
     await expect(controller.unpinSession({ sessionId: session.id }))
-      .resolves.toEqual({ pinnedSessions: [] })
+      .resolves.toEqual({ pinnedSessionIds: [] })
   })
 })
 
@@ -290,19 +290,38 @@ describe('WorkspaceController follow', () => {
           initialized: true,
           workspaceIds: ['missing'],
           archivedSessionIds: [],
-          pinnedSessions: [],
+          pinnedSessionIds: [],
         },
       })
     }).toThrow('references missing Workspace "missing"')
   })
 
+  it('starts a fresh feed with existing pins and follows their removal', async () => {
+    const { controller, ctx, root } = await harness()
+    const session = ctx.sessions.create(SessionId('already-pinned'), { meta: { cwd: root } })
+    await controller.pinSession({ sessionId: session.id })
+    const feed = new WorkspaceFeed(ctx)
+    const abort = new AbortController()
+    const iterator = feed.follow(abort.signal)[Symbol.asyncIterator]()
+    try {
+      await expect(nextFrame(iterator)).resolves.toMatchObject({
+        type: 'baseline', value: { pinnedSessionIds: [session.id] },
+      })
+      await controller.unpinSession({ sessionId: session.id })
+      await expect(nextFrame(iterator)).resolves.toEqual({ type: 'pinned', pinnedSessionIds: [] })
+    } finally {
+      abort.abort()
+      await iterator.return?.()
+    }
+  })
+
   it('starts with a complete baseline and emits committed increments in domain order', async () => {
     const { controller, ctx, root } = await harness()
     const abort = new AbortController()
     const iterator = controller.follow(abort.signal)[Symbol.asyncIterator]()
     await expect(nextFrame(iterator)).resolves.toEqual({
       type: 'baseline',
-      value: { items: [], archivedSessionIds: [], pinnedSessions: [] },
+      value: { items: [], archivedSessionIds: [], pinnedSessionIds: [] },
     })
 
     const first = await controller.create({ path: stageDir(root, 'first') })
@@ -347,12 +366,12 @@ describe('WorkspaceController follow', () => {
     })
     await controller.pinSession({ sessionId: session.id })
     await expect(nextFrame(iterator)).resolves.toEqual({
-      type: 'pinned', pinnedSessions: [{ sessionId: session.id, pinnedAt: expect.any(Number) }],
+      type: 'pinned', pinnedSessionIds: [session.id],
     })
     // Unpin rides the same complete-set increment: no new frame type.
     await controller.unpinSession({ sessionId: session.id })
     await expect(nextFrame(iterator)).resolves.toEqual({
-      type: 'pinned', pinnedSessions: [],
+      type: 'pinned', pinnedSessionIds: [],
     })
     await controller.delete({ workspaceId: second.workspace.workspaceId })
     await expect(nextFrame(iterator)).resolves.toEqual({