fix(swarm): restore the lead's team task list when a session is resumed

CHANGELOG.md

@@ -8,6 +8,7 @@ All notable changes to DreamCoder will be documented in this file.
 
 - Confirmation dialogs keep long workspace paths inside their bounds, so Cancel and Enable remain visible when enabling bypass permissions (#226). Thanks @imshah-id.
 - Images attached from uploads, paste or the built-in browser are kept unchanged within the client limits and resized or compressed when they exceed 2000×2000 pixels or 3.75 MB; a re-encoded image is named after its new type. An image the app cannot decode is attached as it is when it is within 3.75 MB. A file that cannot be attached is named in a message, and the other files picked or dropped with it are still attached. Sent images now use compact thumbnails that still open in the gallery (#218). Thanks @henricop.
+- A lead session that is resumed after a restart keeps using its team's task list (#216). The lead looked for tasks in a list named after its session, so `TaskList` returned nothing and new tasks went to a different list than the one the teammates read. The lead now goes back to the team it created when the session is resumed. Thanks @WhitePepperLambSoup.
 
 ## [0.8.0] — 2026-11-01
 

src/cli/print.ts

@@ -344,6 +344,7 @@ import {
   markMessagesAsRead,
   isShutdownApproved,
 } from '../utils/teammateMailbox.js'
+import { restoreLeaderTeamNameOnResume } from '../utils/swarm/reconnection.js'
 import { removeTeammateFromTeamFile } from '../utils/swarm/teamHelpers.js'
 import { unassignTeammateTasks } from '../utils/tasks.js'
 import { getRunningTasks } from '../utils/task/framework.js'
@@ -735,6 +736,10 @@ export async function runHeadless(
     return
   }
 
+  if (options.continue || options.resume) {
+    restoreLeaderTeamNameOnResume()
+  }
+
   // Handle --rewind-files: restore filesystem and exit immediately
   if (options.rewindFiles) {
     // File history snapshots are only created for user messages,

src/utils/swarm/reconnection.test.ts

@@ -0,0 +1,140 @@
+import { afterEach, beforeEach, describe, expect, it } from 'bun:test'
+import * as fs from 'node:fs/promises'
+import * as os from 'node:os'
+import * as path from 'node:path'
+import { getSessionId } from '../../bootstrap/state.js'
+import {
+  clearLeaderTeamName,
+  createTask,
+  getTaskListId,
+  listTasks,
+  type Task,
+} from '../tasks.js'
+import {
+  restoreLeaderTeamName,
+  restoreLeaderTeamNameOnResume,
+} from './reconnection.js'
+
+const configDirAtLoad = process.env.DREAMCODER_CONFIG_DIR
+const userTypeAtLoad = process.env.USER_TYPE
+const agentTeamsAtLoad = process.env.CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS
+let tmpDir: string
+
+function restoreEnv(name: string, value: string | undefined): void {
+  if (value === undefined) delete process.env[name]
+  else process.env[name] = value
+}
+
+const pendingTask = (subject: string): Omit<Task, 'id'> => ({
+  subject,
+  description: '',
+  status: 'pending',
+  blocks: [],
+  blockedBy: [],
+})
+
+async function writeTeam(
+  name: string,
+  leadSessionId: string,
+  createdAt = 1,
+): Promise<void> {
+  const teamDir = path.join(tmpDir, 'teams', name)
+  await fs.mkdir(teamDir, { recursive: true })
+  await fs.writeFile(
+    path.join(teamDir, 'config.json'),
+    JSON.stringify({
+      name,
+      createdAt,
+      leadAgentId: `team-lead@${name}`,
+      leadSessionId,
+      members: [],
+    }),
+  )
+}
+
+beforeEach(async () => {
+  tmpDir = await fs.mkdtemp(path.join(os.tmpdir(), 'reconnection-'))
+  process.env.DREAMCODER_CONFIG_DIR = tmpDir
+})
+
+afterEach(async () => {
+  clearLeaderTeamName()
+  process.env.DREAMCODER_CONFIG_DIR = configDirAtLoad
+  await fs.rm(tmpDir, { recursive: true, force: true })
+})
+
+describe('restoreLeaderTeamName', () => {
+  it('points the lead back at the team it created before a restart', async () => {
+    await writeTeam('keep-test', getSessionId())
+    await createTask('keep-test', pendingTask('Write the intro'))
+    expect(getTaskListId()).toBe(getSessionId())
+
+    restoreLeaderTeamName()
+
+    expect(getTaskListId()).toBe('keep-test')
+    const tasks = await listTasks(getTaskListId())
+    expect(tasks.map(task => task.subject)).toEqual(['Write the intro'])
+  })
+
+  it('ignores teams led by another session', async () => {
+    await writeTeam('someone-elses', 'another-session')
+
+    restoreLeaderTeamName()
+
+    expect(getTaskListId()).toBe(getSessionId())
+  })
+
+  it('uses the newest team when the session led more than one', async () => {
+    await writeTeam('older', getSessionId(), 1)
+    await writeTeam('newer', getSessionId(), 2)
+
+    restoreLeaderTeamName()
+
+    expect(getTaskListId()).toBe('newer')
+  })
+
+  it('does nothing when no team has been created', () => {
+    restoreLeaderTeamName()
+
+    expect(getTaskListId()).toBe(getSessionId())
+  })
+})
+
+describe('restoreLeaderTeamNameOnResume', () => {
+  beforeEach(() => {
+    delete process.env.USER_TYPE
+    delete process.env.CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS
+  })
+
+  afterEach(() => {
+    restoreEnv('USER_TYPE', userTypeAtLoad)
+    restoreEnv('CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS', agentTeamsAtLoad)
+  })
+
+  it('restores the team name when agent teams are enabled', async () => {
+    process.env.CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS = '1'
+    await writeTeam('keep-test', getSessionId())
+
+    restoreLeaderTeamNameOnResume()
+
+    expect(getTaskListId()).toBe('keep-test')
+  })
+
+  it('restores nothing when agent teams are disabled', async () => {
+    await writeTeam('keep-test', getSessionId())
+
+    restoreLeaderTeamNameOnResume()
+
+    expect(getTaskListId()).toBe(getSessionId())
+  })
+
+  it('does not take over the team of the session it was forked from', async () => {
+    process.env.CLAUDE_CODE_EXPERIMENTAL_AGENT_TEAMS = '1'
+    await writeTeam('original-team', 'original-session')
+    expect(getSessionId()).not.toBe('original-session')
+
+    restoreLeaderTeamNameOnResume()
+
+    expect(getTaskListId()).toBe(getSessionId())
+  })
+})

src/utils/swarm/reconnection.ts

@@ -6,9 +6,15 @@
  * - Resumed sessions: Initialize from teamName/agentName stored in the transcript
  */
 
+import { readdirSync } from 'fs'
+import { getSessionId } from '../../bootstrap/state.js'
 import type { AppState } from '../../state/AppState.js'
+import { isAgentSwarmsEnabled } from '../agentSwarmsEnabled.js'
 import { logForDebugging } from '../debug.js'
+import { getTeamsDir } from '../envUtils.js'
+import { errorMessage, getErrnoCode } from '../errors.js'
 import { logError } from '../log.js'
+import { setLeaderTeamName } from '../tasks.js'
 import { getDynamicTeamContext } from '../teammate.js'
 import { getTeamFilePath, readTeamFile } from './teamHelpers.js'
 
@@ -65,6 +71,37 @@ export function computeInitialTeamContext():
   }
 }
 
+export function restoreLeaderTeamName(): void {
+  let teamNames: string[]
+  try {
+    teamNames = readdirSync(getTeamsDir())
+  } catch (e) {
+    if (getErrnoCode(e) !== 'ENOENT') {
+      logForDebugging(`[Reconnection] Failed to list teams: ${errorMessage(e)}`)
+    }
+    return
+  }
+
+  const sessionId = getSessionId()
+  let newest: { name: string; createdAt: number } | undefined
+  for (const name of teamNames) {
+    const teamFile = readTeamFile(name)
+    if (teamFile?.leadSessionId !== sessionId) continue
+    if (!newest || teamFile.createdAt > newest.createdAt) {
+      newest = { name, createdAt: teamFile.createdAt }
+    }
+  }
+
+  if (newest) {
+    setLeaderTeamName(newest.name)
+  }
+}
+
+export function restoreLeaderTeamNameOnResume(): void {
+  if (!isAgentSwarmsEnabled()) return
+  restoreLeaderTeamName()
+}
+
 /**
  * Initialize teammate context from a resumed session.
  *