feat(workspace): support persistent workspace ordering

packages/client/connection/src/client/fixture.ts

@@ -2408,6 +2408,38 @@ function createFixtureWorld(options: FixtureOptions): FixtureWorld {
         emitHost({ type: 'host/workspace-removed', workspaceId })
         return ok(request, { deleted: true as const })
       },
+      insertBefore: (request) => {
+        const { workspaceId, beforeWorkspaceId } = request.payload
+        const source = workspaces.findIndex(workspace => workspace.workspaceId === workspaceId)
+        const anchor = beforeWorkspaceId === undefined
+          ? workspaces.length
+          : workspaces.findIndex(workspace => workspace.workspaceId === beforeWorkspaceId)
+        const missing = source === -1 ? workspaceId : anchor === -1 ? beforeWorkspaceId : undefined
+        if (missing !== undefined) {
+          return err(request, {
+            code: 'workspace-not-found',
+            message: `no workspace ${missing}`,
+            details: { workspaceId: missing },
+          })
+        }
+        if (beforeWorkspaceId !== workspaceId) {
+          const previousOrder = workspaces.map(candidate => candidate.workspaceId)
+          const [workspace] = workspaces.splice(source, 1)
+          /* v8 ignore next -- source was resolved from the same array immediately above. */
+          if (workspace === undefined) throw new Error(`fixture lost workspace ${workspaceId}`)
+          const at = beforeWorkspaceId === undefined
+            ? workspaces.length
+            : workspaces.findIndex(candidate => candidate.workspaceId === beforeWorkspaceId)
+          workspaces.splice(at, 0, workspace)
+          if (workspaces.some((candidate, index) => candidate.workspaceId !== previousOrder[index])) {
+            emitHost({
+              type: 'host/workspace-order-changed',
+              workspaceIds: workspaces.map(candidate => candidate.workspaceId),
+            })
+          }
+        }
+        return ok(request, { workspaceIds: workspaces.map(candidate => candidate.workspaceId) })
+      },
       insertSessionBefore: (request) => {
         const { workspaceId, sessionId, beforeSessionId } = request.payload
         const workspace = workspaces.find(w => w.workspaceId === workspaceId)
@@ -2949,6 +2981,7 @@ export class FixtureApiClient extends AbstractApiClient {
       case 'workspace.create': return this.api.workspace.create(request)
       case 'workspace.rename': return this.api.workspace.rename(request)
       case 'workspace.delete': return this.api.workspace.delete(request)
+      case 'workspace.insertBefore': return this.api.workspace.insertBefore(request)
       case 'workspace.insertSessionBefore': return this.api.workspace.insertSessionBefore(request)
       case 'workspace.archiveSession': return this.api.workspace.archiveSession(request)
       case 'command.list': return this.api.commands.list(request)

packages/client/runtime/src/client/contract/workspaces.ts

@@ -68,6 +68,12 @@ export interface IWorkspaces {
    * @param workspaceId - target workspace.
    */
   delete(workspaceId: WorkspaceId): Promise<void>
+  /**
+   * Move a Workspace within the registry display order.
+   * @param workspaceId - Workspace to move.
+   * @param beforeWorkspaceId - Anchor workspace; omitted appends.
+   */
+  insertBefore(workspaceId: WorkspaceId, beforeWorkspaceId?: WorkspaceId): Promise<void>
   /**
    * Move an accounted session within/into a Workspace's ordered list.
    * @param workspaceId - target workspace.

packages/client/runtime/src/client/workspaces/manager.ts

@@ -4,7 +4,6 @@ import type {
   HostFrame, IApiClient, RpcError, RpcRequest, RpcResult, SessionId, WorkspaceId, WorkspaceView,
 } from '@deepseek-ai/dsh-client-connection/client'
 import { transportError } from '@deepseek-ai/dsh-host-apiproxy/api'
-import { mergeOrderedBaseline } from '../ordered-baseline.ts'
 import { Notifier } from '../sessions/notifier.ts'
 import { Workspace, type WorkspaceCreateInput } from './workspace.ts'
 
@@ -30,6 +29,7 @@ export interface WorkspaceListSnapshot {
 type WorkspaceDelta =
   | { type: 'upsert'; workspace: WorkspaceView }
   | { type: 'remove'; workspaceId: WorkspaceId }
+  | { type: 'order'; workspaceIds: readonly WorkspaceId[] }
 
 /** Workspace object cluster driven by one list baseline and changed-frame upserts. */
 export class WorkspaceManager {
@@ -51,6 +51,10 @@ export class WorkspaceManager {
    * mirror of replaying refreshFrames over the item baseline.
    */
   private archivedSupersedesRefresh = false
+  /** Latest local reorder request; only its unary echo may install order. */
+  private orderRequestGeneration = 0
+  /** Increments on order frames so a later remote commit outranks an older unary echo. */
+  private orderFrameGeneration = 0
   /**
    * Ids this process has seen removed, kept for the connection's lifetime so
    * a late changed frame or a stale baseline row cannot resurrect a deleted
@@ -72,16 +76,15 @@ export class WorkspaceManager {
 
   /**
    * Refresh from workspace.list. The first successful response establishes
-   * Host order; later responses update membership and values without moving
-   * identities already visible to the client. Frames arriving during the RPC
-   * are replayed over its response.
+   * Host order; later responses re-establish the durable order so reconnects
+   * adopt reorders committed while this client was offline. Frames arriving
+   * during the RPC are replayed over its response.
    * @returns the shared in-flight refresh.
    */
   refresh(): Promise<void> {
     if (this.inflight !== null) return this.inflight
     this.state = 'loading'
     this.error = null
-    const established = this.itemViews()
     const frames: WorkspaceDelta[] = []
     this.refreshFrames = frames
     this.notifier.markDirty()
@@ -89,9 +92,7 @@ export class WorkspaceManager {
       try {
         const { result } = await this.api.workspace.list({})
         if (result.ok) {
-          let items = this.phase === 'pending'
-            ? result.value.items
-            : mergeOrderedBaseline(established, result.value.items, workspace => workspace.workspaceId)
+          let items = result.value.items
           items = items.filter(workspace => !this.removedIds.has(workspace.workspaceId))
           for (const delta of frames) items = applyWorkspaceDelta(items, delta)
           this.installViews(items)
@@ -157,6 +158,35 @@ export class WorkspaceManager {
     return result
   }
 
+  /**
+   * Move a Workspace within the registry display order and install the full
+   * returned order without waiting for the Host frame.
+   * @param workspaceId - Workspace to move.
+   * @param beforeWorkspaceId - Anchor workspace; omitted appends.
+   * @returns the wire result.
+   */
+  async insertBefore(
+    workspaceId: WorkspaceId,
+    beforeWorkspaceId?: WorkspaceId,
+  ): Promise<RpcResult<{ workspaceIds: WorkspaceId[] }>> {
+    const requestGeneration = ++this.orderRequestGeneration
+    const frameGeneration = this.orderFrameGeneration
+    const previousOrder = this.itemViews().map(workspace => workspace.workspaceId)
+    this.installOrder(insertIdBefore(previousOrder, workspaceId, beforeWorkspaceId))
+    const { result } = await this.api.workspace.insertBefore({
+      workspaceId,
+      ...beforeWorkspaceId === undefined ? {} : { beforeWorkspaceId },
+    })
+    if (result.ok && requestGeneration === this.orderRequestGeneration
+      && frameGeneration === this.orderFrameGeneration) {
+      this.installOrder(result.value.workspaceIds)
+    } else if (!result.ok && requestGeneration === this.orderRequestGeneration
+      && frameGeneration === this.orderFrameGeneration) {
+      this.installOrder(previousOrder)
+    }
+    return result
+  }
+
   /**
    * Move a session within its Workspace's manual order, then publish the
    * returned snapshot without waiting for the changed frame.
@@ -198,6 +228,10 @@ export class WorkspaceManager {
   handleHostEnvelope(envelope: RpcRequest<HostFrame>): void {
     if (envelope.payload.type === 'host/workspace-changed') this.upsert(envelope.payload.workspace)
     else if (envelope.payload.type === 'host/workspace-removed') this.remove(envelope.payload.workspaceId)
+    else if (envelope.payload.type === 'host/workspace-order-changed') {
+      this.orderFrameGeneration++
+      this.installOrder(envelope.payload.workspaceIds)
+    }
     else if (envelope.payload.type === 'host/archived-sessions-changed') {
       this.installArchived(envelope.payload.archivedSessionIds)
     }
@@ -249,6 +283,21 @@ export class WorkspaceManager {
     this.notifier.markDirty()
   }
 
+  /** Reorder known Workspace objects by a complete Host id sequence. */
+  private installOrder(workspaceIds: readonly WorkspaceId[]): void {
+    this.refreshFrames?.push({ type: 'order', workspaceIds })
+    const rank = new Map(workspaceIds.map((id, index) => [id, index]))
+    const items = [...this.items].sort((left, right) => {
+      const leftId = left.getSnapshot().view?.workspaceId
+      const rightId = right.getSnapshot().view?.workspaceId
+      return (leftId === undefined ? Number.MAX_SAFE_INTEGER : rank.get(leftId) ?? Number.MAX_SAFE_INTEGER)
+        - (rightId === undefined ? Number.MAX_SAFE_INTEGER : rank.get(rightId) ?? Number.MAX_SAFE_INTEGER)
+    })
+    if (items.every((item, index) => item === this.items[index])) return
+    this.items = items
+    this.notifier.markDirty()
+  }
+
   /** Upsert one Host view, optionally retaining the local object that materialized it. */
   private upsert(view: WorkspaceView, identity?: Workspace): void {
     if (this.removedIds.has(view.workspaceId)) return
@@ -332,7 +381,26 @@ function upsertWorkspace(items: readonly WorkspaceView[], workspace: WorkspaceVi
 
 /** Replay one ordered delta over a baseline: upsert in place, or drop the removed id. */
 function applyWorkspaceDelta(items: readonly WorkspaceView[], delta: WorkspaceDelta): WorkspaceView[] {
-  return delta.type === 'upsert'
-    ? upsertWorkspace(items, delta.workspace)
-    : items.filter(workspace => workspace.workspaceId !== delta.workspaceId)
+  if (delta.type === 'upsert') return upsertWorkspace(items, delta.workspace)
+  if (delta.type === 'remove') {
+    return items.filter(workspace => workspace.workspaceId !== delta.workspaceId)
+  }
+  const rank = new Map(delta.workspaceIds.map((id, index) => [id, index]))
+  return [...items].sort((left, right) =>
+    (rank.get(left.workspaceId) ?? Number.MAX_SAFE_INTEGER)
+    - (rank.get(right.workspaceId) ?? Number.MAX_SAFE_INTEGER))
+}
+
+/** Move one known id before an optional anchor; unknown ids leave the order unchanged. */
+function insertIdBefore(
+  ids: readonly WorkspaceId[],
+  id: WorkspaceId,
+  beforeId?: WorkspaceId,
+): WorkspaceId[] {
+  if (!ids.includes(id) || (beforeId !== undefined && !ids.includes(beforeId)) || beforeId === id) {
+    return [...ids]
+  }
+  const without = ids.filter(candidate => candidate !== id)
+  const at = beforeId === undefined ? without.length : without.indexOf(beforeId)
+  return [...without.slice(0, at), id, ...without.slice(at)]
 }

packages/client/runtime/src/client/workspaces/service.ts

@@ -265,6 +265,16 @@ export class WorkspacesService implements IWorkspaces {
     if (!result.ok) throw new Error(`workspace delete failed: ${result.error.code}: ${result.error.message}`)
   }
 
+  /**
+   * Move a Workspace within the durable registry display order.
+   * @param workspaceId - Workspace to move.
+   * @param beforeWorkspaceId - Anchor workspace; omitted appends.
+   */
+  async insertBefore(workspaceId: WorkspaceId, beforeWorkspaceId?: WorkspaceId): Promise<void> {
+    const result = await this.manager.insertBefore(workspaceId, beforeWorkspaceId)
+    if (!result.ok) throw new Error(`workspace reorder failed: ${result.error.code}: ${result.error.message}`)
+  }
+
   /**
    * Archive a session into the registry-global set. Clearing an archived
    * current selection is the projection sweep's job (one rule for the local

packages/client/test-runtime/src/workspaces.ts

@@ -172,6 +172,16 @@ export class TestWorkspaces implements IWorkspaces {
     await (this.stubs.get('delete')?.(workspaceId) as Promise<void> | undefined)
   }
 
+  /**
+   * Move a Workspace in display order (recorded; default no-op).
+   * @param workspaceId - Workspace to move.
+   * @param beforeWorkspaceId - Anchor; omitted appends.
+   */
+  async insertBefore(workspaceId: WorkspaceId, beforeWorkspaceId?: WorkspaceId): Promise<void> {
+    this.calls.push({ method: 'insertBefore', args: [workspaceId, beforeWorkspaceId] })
+    await (this.stubs.get('insertBefore')?.(workspaceId, beforeWorkspaceId) as Promise<void> | undefined)
+  }
+
   /**
    * Move an accounted session (recorded). The default echoes a minimal view.
    * @param workspaceId - target workspace.

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

@@ -25,7 +25,7 @@ import { isUserInvocable } from '@deepseek-ai/dsh-skill'
 import type { Workspace, WorkspaceRecord } from '@deepseek-ai/dsh-workspace'
 import {
   workspaceDomainState, workspaceRecord, WorkspaceId as brandWorkspaceId,
-  WorkspaceMoveInvalidError, WorkspaceUnknownSessionError,
+  WorkspaceMoveInvalidError, WorkspaceOrderInvalidError, WorkspaceUnknownSessionError,
 } from '@deepseek-ai/dsh-workspace'
 // Type-only: brings the `ctx.tools` Context merge into this program (viewFor reads presenters).
 import {
@@ -2671,6 +2671,20 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
         return ok(request, { deleted: true as const })
       },
 
+      async insertBefore(request) {
+        const { workspaceId, beforeWorkspaceId } = request.payload
+        try {
+          const workspaceIds = await ctx.workspace.insertBefore(
+            brandWorkspaceId(workspaceId),
+            beforeWorkspaceId === undefined ? undefined : brandWorkspaceId(beforeWorkspaceId),
+          )
+          return ok(request, { workspaceIds: [...workspaceIds] })
+        } catch (error: unknown) {
+          if (!(error instanceof WorkspaceOrderInvalidError)) throw error
+          return workspaceNotFound(request, error.workspaceId)
+        }
+      },
+
       async insertSessionBefore(request) {
         const { payload } = request
         const workspace = ctx.workspace.get(brandWorkspaceId(payload.workspaceId))
@@ -3370,6 +3384,7 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
         const committedWorkspaceIds = new Set(
           ctx.workspace.list().map(workspace => String(workspace.id)),
         )
+        let committedWorkspaceOrder = ctx.workspace.list().map(workspace => workspaceView(workspace).workspaceId)
         // Frame-dedup baseline, same posture as committedWorkspaceIds: the
         // stream opens against the current set; workspace.list re-baselines
         // reconnecting clients, so only later changes need frames.
@@ -3401,6 +3416,9 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
             if (change.table === '') {
               if (change.operation !== 'put') return
               const state = workspaceDomainState.parse(change.value)
+              const orderChanged = state.workspaceIds.length === committedWorkspaceOrder.length
+                && state.workspaceIds.every(workspaceId => committedWorkspaceIds.has(String(workspaceId)))
+                && state.workspaceIds.some((workspaceId, index) => workspaceId !== committedWorkspaceOrder[index])
               for (const workspaceId of state.workspaceIds) {
                 if (committedWorkspaceIds.has(workspaceId)) continue
                 const workspace = ctx.workspace.get(workspaceId)
@@ -3410,6 +3428,13 @@ export function createApiProxy(ctx: Context, defaults: ApiProxyDefaults): ApiPro
                 committedWorkspaceIds.add(workspaceId)
                 queue.push(frame({ type: 'host/workspace-changed', workspace: workspaceView(workspace) }))
               }
+              committedWorkspaceOrder = [...state.workspaceIds]
+              if (orderChanged) {
+                queue.push(frame({
+                  type: 'host/workspace-order-changed',
+                  workspaceIds: [...state.workspaceIds],
+                }))
+              }
               if (state.archivedSessionIds.length !== archivedSessionIds.length
                 || state.archivedSessionIds.some((id, index) => id !== archivedSessionIds[index])) {
                 archivedSessionIds = state.archivedSessionIds

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

@@ -83,6 +83,7 @@ export const hostFrameSchema = z.discriminatedUnion('type', [
   z.object({ type: z.literal('host/agent-error'), sessionId: sessionIdSchema, message: z.string() }),
   z.object({ type: z.literal('host/workspace-changed'), workspace: workspaceViewSchema }),
   z.object({ type: z.literal('host/workspace-removed'), workspaceId: workspaceIdSchema }),
+  z.object({ type: z.literal('host/workspace-order-changed'), workspaceIds: z.array(workspaceIdSchema) }),
   z.object({ type: z.literal('host/archived-sessions-changed'), archivedSessionIds: z.array(sessionIdSchema) }),
   z.object({ type: z.literal('host/commands-changed') }),
   z.object({ type: z.literal('host/session-preset-changed'), sessionId: sessionIdSchema, agentPreset: z.string() }),

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

@@ -119,7 +119,8 @@ export type MuxFrame =
  * workspace mutation (create/attach/order change — the client upserts, while
  * `workspace.list` provides the reconnect baseline); workspace-removed is the
  * committed registration-deletion increment and never implies directory or
- * session-log deletion; archived-sessions-changed pushes the full registry
+ * session-log deletion; workspace-order-changed pushes the complete durable
+ * registry order after a reorder; archived-sessions-changed pushes the full registry
  * archive set after every durable change (same full-snapshot posture as
  * workspace-changed — `workspace.list` re-baselines it on reconnect).
  */
@@ -139,6 +140,7 @@ export type HostFrame =
   | { type: 'host/agent-error'; sessionId: SessionId; message: string }
   | { type: 'host/workspace-changed'; workspace: WorkspaceView }
   | { type: 'host/workspace-removed'; workspaceId: WorkspaceView['workspaceId'] }
+  | { type: 'host/workspace-order-changed'; workspaceIds: WorkspaceView['workspaceId'][] }
   | { type: 'host/archived-sessions-changed'; archivedSessionIds: SessionId[] }
   /**
    * The command registry changed (`commands/change` passthrough). Pure

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

@@ -48,6 +48,7 @@ export interface RpcMethodMap {
   'workspace.create': WorkspaceApi['create']
   'workspace.rename': WorkspaceApi['rename']
   'workspace.delete': WorkspaceApi['delete']
+  'workspace.insertBefore': WorkspaceApi['insertBefore']
   'workspace.insertSessionBefore': WorkspaceApi['insertSessionBefore']
   'workspace.archiveSession': WorkspaceApi['archiveSession']
   'command.list': CommandsApi['list']

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

@@ -66,6 +66,17 @@ export const workspaceDeleteValueSchema = z.object({
   deleted: z.literal(true),
 }) satisfies z.ZodType<Wire<ResponseValue<'workspace.delete'>>>
 
+/** workspace.insertBefore request payload (anchor omitted = append to end). */
+export const workspaceInsertBeforeRequestSchema = z.object({
+  workspaceId: workspaceIdSchema,
+  beforeWorkspaceId: workspaceIdSchema.optional(),
+}) satisfies z.ZodType<Wire<RequestPayload<'workspace.insertBefore'>>>
+
+/** workspace.insertBefore response value: the complete durable display order. */
+export const workspaceInsertBeforeValueSchema = z.object({
+  workspaceIds: z.array(workspaceIdSchema),
+}) satisfies z.ZodType<Wire<ResponseValue<'workspace.insertBefore'>>>
+
 /** workspace.insertSessionBefore request payload (anchor omitted = append to end). */
 export const workspaceInsertSessionBeforeRequestSchema = z.object({
   workspaceId: workspaceIdSchema,

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

@@ -73,6 +73,15 @@ export interface WorkspaceApi {
   delete(request: RpcRequest<{ workspaceId: WorkspaceId }>):
   Promise<RpcResponse<{ deleted: true }>>
 
+  /**
+   * Moves one Workspace within the registry display order,
+   * DOM-insertBefore-like. An omitted anchor appends to the end.
+   */
+  insertBefore(request: RpcRequest<{
+    workspaceId: WorkspaceId
+    beforeWorkspaceId?: WorkspaceId
+  }>): Promise<RpcResponse<{ workspaceIds: WorkspaceId[] }>>
+
   /**
    * Moves an accounted session within its workspace's manual order,
    * DOM-insertBefore-like: with `beforeSessionId` the session is inserted

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

@@ -35,6 +35,7 @@ import {
   workspaceArchiveSessionValueSchema,
   workspaceCreateValueSchema,
   workspaceDeleteValueSchema,
+  workspaceInsertBeforeValueSchema,
   workspaceInsertSessionBeforeValueSchema,
   workspaceListValueSchema,
   workspaceRenameValueSchema,
@@ -117,6 +118,7 @@ export interface IApiClient {
     create(payload: RequestPayload<'workspace.create'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.create'>>>
     rename(payload: RequestPayload<'workspace.rename'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.rename'>>>
     delete(payload: RequestPayload<'workspace.delete'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.delete'>>>
+    insertBefore(payload: RequestPayload<'workspace.insertBefore'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.insertBefore'>>>
     insertSessionBefore(payload: RequestPayload<'workspace.insertSessionBefore'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.insertSessionBefore'>>>
     archiveSession(payload: RequestPayload<'workspace.archiveSession'>, signal?: AbortSignal): Promise<RpcResponse<ResponseValue<'workspace.archiveSession'>>>
   }
@@ -198,6 +200,7 @@ const UNARY_VALUE_SCHEMAS: { [K in keyof RpcMethodMap]: z.ZodType<Wire<ResponseV
   'workspace.create': workspaceCreateValueSchema,
   'workspace.rename': workspaceRenameValueSchema,
   'workspace.delete': workspaceDeleteValueSchema,
+  'workspace.insertBefore': workspaceInsertBeforeValueSchema,
   'workspace.insertSessionBefore': workspaceInsertSessionBeforeValueSchema,
   'workspace.archiveSession': workspaceArchiveSessionValueSchema,
   'command.list': commandListValueSchema,
@@ -452,6 +455,7 @@ export abstract class AbstractApiClient implements IApiClient {
     create: (payload, signal) => this.callUnary('workspace.create', payload, signal),
     rename: (payload, signal) => this.callUnary('workspace.rename', payload, signal),
     delete: (payload, signal) => this.callUnary('workspace.delete', payload, signal),
+    insertBefore: (payload, signal) => this.callUnary('workspace.insertBefore', payload, signal),
     insertSessionBefore: (payload, signal) => this.callUnary('workspace.insertSessionBefore', payload, signal),
     archiveSession: (payload, signal) => this.callUnary('workspace.archiveSession', payload, signal),
   }

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

@@ -38,6 +38,7 @@ import {
   workspaceArchiveSessionRequestSchema,
   workspaceCreateRequestSchema,
   workspaceDeleteRequestSchema,
+  workspaceInsertBeforeRequestSchema,
   workspaceInsertSessionBeforeRequestSchema,
   workspaceListRequestSchema,
   workspaceRenameRequestSchema,
@@ -113,6 +114,7 @@ const UNARY_ROUTES: UnaryRoutes = {
   'workspace.create': { schema: workspaceCreateRequestSchema, invoke: (api, r) => api.workspace.create(r) },
   'workspace.rename': { schema: workspaceRenameRequestSchema, invoke: (api, r) => api.workspace.rename(r) },
   'workspace.delete': { schema: workspaceDeleteRequestSchema, invoke: (api, r) => api.workspace.delete(r) },
+  'workspace.insertBefore': { schema: workspaceInsertBeforeRequestSchema, invoke: (api, r) => api.workspace.insertBefore(r) },
   'workspace.insertSessionBefore': { schema: workspaceInsertSessionBeforeRequestSchema, invoke: (api, r) => api.workspace.insertSessionBefore(r) },
   'workspace.archiveSession': { schema: workspaceArchiveSessionRequestSchema, invoke: (api, r) => api.workspace.archiveSession(r) },
   'command.list': { schema: commandListRequestSchema, invoke: (api, r) => api.commands.list(r) },

packages/workspace/workspace/src/index.ts

@@ -52,6 +52,17 @@ export class WorkspaceUnknownSessionError extends Error {
   }
 }
 
+/** A workspace reorder named a source or anchor absent from the durable registry order. */
+export class WorkspaceOrderInvalidError extends Error {
+  /**
+   * @param workspaceId - Missing source or anchor id.
+   */
+  constructor(readonly workspaceId: WorkspaceId) {
+    super(`cannot reorder unknown workspace '${workspaceId}'`)
+    this.name = 'WorkspaceOrderInvalidError'
+  }
+}
+
 
 declare module '@deepseek-ai/cordis' {
   interface Context {
@@ -189,6 +200,30 @@ export class WorkspaceRegistry extends Service {
     return this.enqueueOperation(() => this.deleteKnown(id))
   }
 
+  /**
+   * Move one workspace within the durable display order, DOM-insertBefore-like.
+   * With an anchor it lands before that workspace; without one it appends.
+   * @param id - Workspace to move.
+   * @param beforeId - Workspace anchor; omitted appends.
+   * @returns the complete committed workspace order.
+   */
+  insertBefore(id: WorkspaceId, beforeId?: WorkspaceId): Promise<readonly WorkspaceId[]> {
+    return this.enqueueOperation(async () => {
+      const state = this.requireState()
+      if (!state.workspaceIds.includes(id)) throw new WorkspaceOrderInvalidError(id)
+      if (beforeId !== undefined && !state.workspaceIds.includes(beforeId)) {
+        throw new WorkspaceOrderInvalidError(beforeId)
+      }
+      if (beforeId === id) return state.workspaceIds
+      const without = state.workspaceIds.filter(workspaceId => workspaceId !== id)
+      const at = beforeId === undefined ? without.length : without.indexOf(beforeId)
+      const workspaceIds = [...without.slice(0, at), id, ...without.slice(at)]
+      if (sameIds(workspaceIds, state.workspaceIds)) return state.workspaceIds
+      await this.setState({ ...state, workspaceIds })
+      return workspaceIds
+    })
+  }
+
   /**
    * The registry-global archive set: sessions hidden from every grouping
    * surface. Archiving never touches workspace accounting — an archived