diff --git a/apps/server/src/app.ts b/apps/server/src/app.ts
index 96758aa79..231aaeffe 100644
--- a/apps/server/src/app.ts
+++ b/apps/server/src/app.ts
@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT license.
 
-import { existsSync, unlinkSync } from 'node:fs';
+import { unlinkSync } from 'node:fs';
 import { tmpdir } from 'node:os';
 import { join } from 'node:path';
 
@@ -25,13 +25,10 @@ import {
   externalAgentRuntimeConfigRoutes,
   getExternalAgentRuntimeConfig,
   getAgentProfileRegistry,
-  getSupervisedAgentletId,
   installAcpProfileCachePort,
   mountAgenetes,
   resolveDaemonEntry,
 } from './modules/agent/acp/index.js';
-import { buildLegacyCommandProfiles } from './modules/agent/acp/legacy-profile-migration.js';
-import { listProfiles as listLegacyAcpProfiles } from './modules/agent/acp/profile-store.js';
 import { initializeAgentDefaults } from './modules/agent/agent-defaults.js';
 import agentDefaultsRoutes from './modules/agent/agent-defaults.route.js';
 import agentRoutes from './modules/agent/agent.route.js';
@@ -317,15 +314,7 @@ const agentletGateway = mountAgenetes(app, {
   profiles: {
     storageDir: join(getDataDir(), 'agent-profiles'),
     legacyStorageDir: join(getDataDir(), 'agent-team'),
-    legacyCommandProfiles: existsSync(
-      join(getDataDir(), 'agent-profiles', 'registry.json'),
-    )
-      ? []
-      : buildLegacyCommandProfiles(
-          listLegacyAcpProfiles(),
-          getSupervisedAgentletId(),
-          process.cwd(),
-        ),
+    legacyCommandProfiles: [],
   },
 });
 let unregisterHarnessDiscovery: (() => void) | undefined;
diff --git a/apps/server/src/modules/agent/acp/agent-cli.route.test.ts b/apps/server/src/modules/agent/acp/agent-cli.route.test.ts
index a02f85b31..a8b3aae5c 100644
--- a/apps/server/src/modules/agent/acp/agent-cli.route.test.ts
+++ b/apps/server/src/modules/agent/acp/agent-cli.route.test.ts
@@ -12,8 +12,10 @@ import type { FastifyInstance } from 'fastify';
 const mocks = vi.hoisted(() => ({ getProfile: vi.fn(), discover: vi.fn() }));
 vi.mock('@agenetes/agentlet-host', () => ({
   getAgentProfileRegistry: () => ({ getProfile: mocks.getProfile }),
-  getSupervisedAgentletId: () => 'supervised',
-  getAgentletGateway: () => ({ discoverHarnesses: mocks.discover }),
+  getAgentletGateway: () => ({
+    getAgentlet: () => ({ status: 'connected' }),
+    discoverHarnesses: mocks.discover,
+  }),
 }));
 
 let app: FastifyInstance | undefined;
@@ -52,7 +54,7 @@ describe('ACP agent CLI route', () => {
 
     const response = await app.inject({
       method: 'GET',
-      url: '/api/acp/agent-cli',
+      url: '/api/acp/agent-cli?agentletId=machine-a',
     });
 
     expect(response.statusCode).toBe(200);
@@ -72,7 +74,7 @@ describe('ACP agent CLI route', () => {
 
     const response = await app.inject({
       method: 'GET',
-      url: '/api/acp/agent-cli',
+      url: '/api/acp/agent-cli?agentletId=machine-a',
       remoteAddress: '192.0.2.10',
     });
 
@@ -92,7 +94,7 @@ describe('ACP agent CLI route', () => {
 
     const response = await app.inject({
       method: 'GET',
-      url: '/api/acp/agent-cli',
+      url: '/api/acp/agent-cli?agentletId=machine-a',
       remoteAddress: '192.0.2.10',
     });
 
@@ -108,7 +110,9 @@ describe('ACP agent CLI route', () => {
       ),
       { prefix: '/api/acp' },
     );
-    const response = await app.inject('/api/acp/agent-cli');
+    const response = await app.inject(
+      '/api/acp/agent-cli?agentletId=machine-a',
+    );
     expect(response.statusCode).toBe(503);
     expect(response.json().code).toBe('harness_discovery_unavailable');
     expect(response.json()).not.toHaveProperty('agents');
diff --git a/apps/server/src/modules/agent/acp/agent-cli.route.ts b/apps/server/src/modules/agent/acp/agent-cli.route.ts
index 116e1915a..24d053434 100644
--- a/apps/server/src/modules/agent/acp/agent-cli.route.ts
+++ b/apps/server/src/modules/agent/acp/agent-cli.route.ts
@@ -17,7 +17,6 @@
 
 import {
   getAgentletGateway,
-  getSupervisedAgentletId,
   getAgentProfileRegistry,
 } from '@agenetes/agentlet-host';
 import {
@@ -36,19 +35,25 @@ import type {
 } from '@huabu/shared';
 import type { FastifyPluginAsync } from 'fastify';
 
-async function detectAgentClis(profileId?: string): Promise<AcpAgentCliInfo[]> {
+async function detectAgentClis(target: {
+  profileId?: string;
+  agentletId?: string;
+}): Promise<AcpAgentCliInfo[]> {
   const gateway = getAgentletGateway();
   if (!gateway) throw new Error('Agentlet Gateway is not ready');
-  const profile = profileId
-    ? getAgentProfileRegistry()?.getProfile(profileId)
+  const profile = target.profileId
+    ? getAgentProfileRegistry()?.getProfile(target.profileId)
     : undefined;
-  if (profileId && !profile) throw new Error('Agent Profile is unavailable');
-  const result = await gateway.discoverHarnesses(
-    profile?.agentletId ?? getSupervisedAgentletId(),
-    {
-      prepareWorkspaces: false,
-    },
-  );
+  if (target.profileId && !profile)
+    throw new Error('Agent Profile is unavailable');
+  const agentletId = profile?.agentletId ?? target.agentletId;
+  if (!agentletId) throw new Error('Agentlet target is required');
+  const connection = gateway.getAgentlet(agentletId);
+  if (connection?.status !== 'connected')
+    throw new Error('Agentlet is not connected');
+  const result = await gateway.discoverHarnesses(agentletId, {
+    prepareWorkspaces: false,
+  });
   if (result.harnesses.some((entry) => entry.id === CUSTOM_COMMAND_WRAPPER_ID))
     return result.harnesses;
   return [
@@ -96,7 +101,7 @@ export function createAcpAgentCliRoutes(
               message: 'Agent Profile is unavailable',
             });
           }
-          return { agents: await detect(parsed.data.profileId) };
+          return { agents: await detect(parsed.data) };
         } catch (error) {
           request.log.warn(
             { err: error },
diff --git a/apps/server/src/modules/agent/acp/daemon-auth.test.ts b/apps/server/src/modules/agent/acp/daemon-auth.test.ts
index 7fad62a5c..975015cea 100644
--- a/apps/server/src/modules/agent/acp/daemon-auth.test.ts
+++ b/apps/server/src/modules/agent/acp/daemon-auth.test.ts
@@ -32,7 +32,7 @@ function makeAgentletHello(): AgentletHelloParams {
     agentletId: 'test:agentlet',
     agentletProfile: {
       bridge: { name: 'agentlet', version: '1.0.0' },
-      machine: { hostname: 'test', platform: 'linux' },
+      machine: { hostname: 'test', platform: 'linux', arch: 'x64' },
       capabilities: { autoRestart: true, bufferLimit: 1000 },
     },
   };
diff --git a/apps/server/src/modules/agent/acp/index.ts b/apps/server/src/modules/agent/acp/index.ts
index 45b29ac2e..e2d0430e9 100644
--- a/apps/server/src/modules/agent/acp/index.ts
+++ b/apps/server/src/modules/agent/acp/index.ts
@@ -4,7 +4,6 @@
 export {
   mountAgenetes,
   getAgentProfileRegistry,
-  getSupervisedAgentletId,
   ACP_UPGRADE_PATH,
 } from '@agenetes/agentlet-host';
 export type {
diff --git a/apps/server/src/modules/agent/acp/legacy-profile-migration.test.ts b/apps/server/src/modules/agent/acp/legacy-profile-migration.test.ts
deleted file mode 100644
index 2b8afabb5..000000000
--- a/apps/server/src/modules/agent/acp/legacy-profile-migration.test.ts
+++ /dev/null
@@ -1,75 +0,0 @@
-// Copyright (c) Microsoft Corporation.
-// Licensed under the MIT license.
-
-import { describe, expect, it } from 'vitest';
-
-import { buildLegacyCommandProfiles } from './legacy-profile-migration.js';
-
-import type { AcpAgentProfile } from '@huabu/shared';
-
-function makeProfile(
-  overrides: Partial<AcpAgentProfile> = {},
-): AcpAgentProfile {
-  return {
-    id: 'legacy-profile',
-    displayName: 'Legacy Profile',
-    cliId: 'copilot',
-    command: 'copilot --acp',
-    cwd: '/workspace',
-    autoRestart: true,
-    createdAt: 1,
-    updatedAt: 1,
-    ...overrides,
-  };
-}
-
-describe('buildLegacyCommandProfiles', () => {
-  it('preserves ordinary profile identity and launch fields', () => {
-    expect(
-      buildLegacyCommandProfiles(
-        [makeProfile()],
-        'local-agentlet',
-        '/server-cwd',
-      ),
-    ).toEqual([
-      {
-        id: 'legacy-profile',
-        alias: 'Legacy Profile',
-        agentletId: 'local-agentlet',
-        command: 'copilot --acp',
-        workingDirPath: '/workspace',
-        metadata: { cliId: 'copilot' },
-      },
-    ]);
-  });
-
-  it('uses the inherited host directory when an old profile omitted cwd', () => {
-    const [profile] = buildLegacyCommandProfiles(
-      [makeProfile({ cwd: undefined })],
-      'local-agentlet',
-      '/server-cwd',
-    );
-
-    expect(profile?.workingDirPath).toBe('/server-cwd');
-  });
-
-  it('leaves legacy Agent Team records unmigrated', () => {
-    expect(
-      buildLegacyCommandProfiles(
-        [makeProfile({ id: 'team', cliId: 'agent-team' })],
-        'local-agentlet',
-        '/server-cwd',
-      ),
-    ).toEqual([]);
-  });
-
-  it('fails explicitly for an ordinary record without a command', () => {
-    expect(() =>
-      buildLegacyCommandProfiles(
-        [makeProfile({ command: undefined })],
-        'local-agentlet',
-        '/server-cwd',
-      ),
-    ).toThrow("Legacy command Profile 'legacy-profile' has no command");
-  });
-});
diff --git a/apps/server/src/modules/agent/acp/legacy-profile-migration.ts b/apps/server/src/modules/agent/acp/legacy-profile-migration.ts
deleted file mode 100644
index 474278013..000000000
--- a/apps/server/src/modules/agent/acp/legacy-profile-migration.ts
+++ /dev/null
@@ -1,34 +0,0 @@
-// Copyright (c) Microsoft Corporation.
-// Licensed under the MIT license.
-
-import type { CreateAcpCommandProfileInput } from '@agenetes/agent-profile';
-import type { AcpAgentProfile } from '@huabu/shared';
-
-/**
- * Convert spawnable legacy ACP profiles into unified command Profiles.
- *
- * Older records may omit `cwd`; the old launcher then inherited the host
- * process directory, so migration makes that implicit behavior explicit.
- */
-export function buildLegacyCommandProfiles(
-  profiles: AcpAgentProfile[],
-  agentletId: string,
-  defaultWorkingDir: string,
-): CreateAcpCommandProfileInput[] {
-  return profiles.flatMap((profile) => {
-    if (profile.cliId === 'agent-team') return [];
-    if (!profile.command?.trim()) {
-      throw new Error(`Legacy command Profile '${profile.id}' has no command`);
-    }
-    return [
-      {
-        id: profile.id,
-        alias: profile.displayName,
-        agentletId,
-        command: profile.command,
-        workingDirPath: profile.cwd ?? defaultWorkingDir,
-        metadata: { cliId: profile.cliId },
-      },
-    ];
-  });
-}
diff --git a/apps/server/src/modules/agent/acp/profile-store.test.ts b/apps/server/src/modules/agent/acp/profile-store.test.ts
deleted file mode 100644
index cc70c2b81..000000000
--- a/apps/server/src/modules/agent/acp/profile-store.test.ts
+++ /dev/null
@@ -1,74 +0,0 @@
-// Copyright (c) Microsoft Corporation.
-// Licensed under the MIT license.
-
-import { mkdtempSync, readFileSync, rmSync, writeFileSync } from 'node:fs';
-import { tmpdir } from 'node:os';
-import { join } from 'node:path';
-
-import { afterEach, beforeEach, describe, expect, it } from 'vitest';
-
-import { listProfiles } from './profile-store.js';
-
-let directory: string;
-let previousDataDir: string | undefined;
-
-const commandProfile = {
-  id: 'command',
-  displayName: 'Copilot',
-  cliId: 'copilot',
-  command: 'copilot --acp',
-  cwd: '/workspace',
-  autoRestart: true,
-  createdAt: 1,
-  updatedAt: 1,
-};
-
-beforeEach(() => {
-  directory = mkdtempSync(join(tmpdir(), 'huabu-legacy-profiles-'));
-  previousDataDir = process.env.HUABU_DATA_DIR;
-  process.env.HUABU_DATA_DIR = directory;
-});
-
-afterEach(() => {
-  if (previousDataDir === undefined) delete process.env.HUABU_DATA_DIR;
-  else process.env.HUABU_DATA_DIR = previousDataDir;
-  rmSync(directory, { recursive: true, force: true });
-});
-
-describe('read-only legacy Profile import source', () => {
-  it('returns no records for an absent file', () => {
-    expect(listProfiles()).toEqual([]);
-  });
-
-  it('reads ordinary Profiles without rewriting retired Team data', () => {
-    const file = join(directory, 'agent-profiles.json');
-    const original = JSON.stringify({
-      schemaVersion: 1,
-      profiles: [
-        commandProfile,
-        {
-          id: 'retired-team',
-          cliId: 'agent-team',
-          agentTeam: { agentDir: '/team' },
-        },
-        { ...commandProfile, id: 'team-disguised-as-command', agentTeam: {} },
-      ],
-    });
-    writeFileSync(file, original);
-    expect(listProfiles()).toEqual([commandProfile]);
-    expect(readFileSync(file, 'utf8')).toBe(original);
-  });
-
-  it.each([
-    '{"profiles": []}',
-    '{"schemaVersion": 999, "profiles": []}',
-    '{"schemaVersion": 1, "profiles": [{}]}',
-    '{invalid',
-  ])(
-    'rejects corrupt or unsupported data rather than silently losing it',
-    (text) => {
-      writeFileSync(join(directory, 'agent-profiles.json'), text);
-      expect(() => listProfiles()).toThrow();
-    },
-  );
-});
diff --git a/apps/server/src/modules/agent/acp/profile-store.ts b/apps/server/src/modules/agent/acp/profile-store.ts
deleted file mode 100644
index 21437bc56..000000000
--- a/apps/server/src/modules/agent/acp/profile-store.ts
+++ /dev/null
@@ -1,64 +0,0 @@
-// Copyright (c) Microsoft Corporation.
-// Licensed under the MIT license.
-
-import { readFileSync } from 'node:fs';
-import { join } from 'node:path';
-
-import { acpAgentProfileSchema } from '@huabu/shared';
-
-import { getDataDir } from '../../../data-dir.js';
-import { logger } from '../../../utils/logger.js';
-
-import type { AcpAgentProfile } from '@huabu/shared';
-
-/** Read the pre-registry command data once during migration; never rewrite it. */
-export function listProfiles(): AcpAgentProfile[] {
-  let text: string;
-  try {
-    text = readFileSync(join(getDataDir(), 'agent-profiles.json'), 'utf8');
-  } catch (error) {
-    if (error instanceof Error && 'code' in error && error.code === 'ENOENT') {
-      return [];
-    }
-    throw error;
-  }
-  const file: unknown = JSON.parse(text);
-  if (
-    !file ||
-    typeof file !== 'object' ||
-    !('schemaVersion' in file) ||
-    file.schemaVersion !== 1 ||
-    !('profiles' in file) ||
-    !Array.isArray(file.profiles)
-  ) {
-    throw new Error('Unsupported legacy command Profile file');
-  }
-
-  const profiles: AcpAgentProfile[] = [];
-  let retired = 0;
-  for (const raw of file.profiles) {
-    if (
-      raw &&
-      typeof raw === 'object' &&
-      (raw.cliId === 'agent-team' ||
-        Object.prototype.hasOwnProperty.call(raw, 'agentTeam'))
-    ) {
-      retired += 1;
-      continue;
-    }
-    const parsed = acpAgentProfileSchema.safeParse(raw);
-    if (!parsed.success) {
-      throw new Error(
-        `Invalid legacy command Profile: ${parsed.error.message}`,
-      );
-    }
-    profiles.push(parsed.data);
-  }
-  if (retired) {
-    logger.warn(
-      { retired },
-      '[acp] legacy Agent Team records retained as data only',
-    );
-  }
-  return profiles.sort((left, right) => left.createdAt - right.createdAt);
-}
diff --git a/apps/server/src/modules/agent/acp/profiles.route.test.ts b/apps/server/src/modules/agent/acp/profiles.route.test.ts
index bd206adb8..dab86c012 100644
--- a/apps/server/src/modules/agent/acp/profiles.route.test.ts
+++ b/apps/server/src/modules/agent/acp/profiles.route.test.ts
@@ -20,6 +20,7 @@ const mocks = vi.hoisted(() => ({
   initializeDefaults: vi.fn(),
   discoverHarnesses: vi.fn(),
   buildHarnessLaunch: vi.fn(),
+  connectedIds: new Set(['machine-a', 'remote-machine']),
 }));
 
 vi.mock('../agent-defaults.js', () => ({
@@ -32,10 +33,23 @@ vi.mock('@agenetes/agentlet-host', () => ({
   getDaemonSupervisor: () => ({
     getStatus: () => ({ online: true, restartAttempt: 0 }),
   }),
-  getSupervisedAgentletId: () => 'machine-a',
   getAgentletGateway: () => ({
     discoverHarnesses: mocks.discoverHarnesses,
     buildHarnessLaunch: mocks.buildHarnessLaunch,
+    getAgentlets: () =>
+      [...mocks.connectedIds].map((agentletId) => ({
+        agentletId,
+        status: 'connected',
+        connectedAt: new Date('2026-01-01T00:00:00.000Z'),
+        agentletProfile: {
+          bridge: { name: 'agentlet', version: '1.0.0' },
+          machine: {
+            hostname: `${agentletId}-host`,
+            platform: 'linux',
+            arch: 'x64',
+          },
+        },
+      })),
   }),
 }));
 
@@ -92,7 +106,12 @@ describe('ordinary Profile catalog routes', () => {
     const response = await server.inject({
       method: 'POST',
       url: '/api/acp/profiles',
-      payload: { alias: 'Typed', workingDirPath: '/work', launch },
+      payload: {
+        alias: 'Typed',
+        agentletId: 'machine-a',
+        workingDirPath: '/work',
+        launch,
+      },
     });
     expect(response.statusCode).toBe(200);
     expect(mocks.discoverHarnesses).toHaveBeenCalledWith('machine-a', {
@@ -122,6 +141,7 @@ describe('ordinary Profile catalog routes', () => {
         url: '/api/acp/profiles',
         payload: {
           alias: 'Typed',
+          agentletId: 'machine-a',
           workingDirPath: '/work',
           launch: { kind: 'acp-harness', harnessId: 'copilot' },
         },
@@ -139,6 +159,7 @@ describe('ordinary Profile catalog routes', () => {
       url: '/api/acp/profiles',
       payload: {
         alias: 'Copilot',
+        agentletId: 'machine-a',
         workingDirPath: '/work/project',
         launch: commandProfile.launch,
         metadata: { cliId: 'copilot' },
@@ -166,6 +187,16 @@ describe('ordinary Profile catalog routes', () => {
     expect(response.json()).toMatchObject({
       profiles: [commandProfile],
       selectableProfileIds: ['command-1'],
+      connectedDevices: [
+        expect.objectContaining({
+          agentletId: 'machine-a',
+          profileCount: 1,
+        }),
+        expect.objectContaining({
+          agentletId: 'remote-machine',
+          profileCount: 0,
+        }),
+      ],
     });
     expect(mocks.registry.createProfile).not.toHaveBeenCalled();
     expect(mocks.initializeDefaults).not.toHaveBeenCalled();
@@ -179,6 +210,7 @@ describe('ordinary Profile catalog routes', () => {
       url: '/api/acp/profiles',
       payload: {
         alias: 'Forged',
+        agentletId: 'machine-a',
         workingDirPath: '/work',
         launch: commandProfile.launch,
         customData: { discoveredAgent: source },
@@ -419,7 +451,10 @@ describe('ordinary Profile catalog routes', () => {
     const response = await server.inject({
       method: 'POST',
       url: '/api/acp/profile-launch-preview',
-      payload: { launch: commandProfile.launch },
+      payload: {
+        agentletId: 'machine-a',
+        launch: commandProfile.launch,
+      },
     });
     expect(response.statusCode).toBe(503);
     expect(response.json().code).toBe('harness_preview_unavailable');
diff --git a/apps/server/src/modules/agent/acp/profiles.route.ts b/apps/server/src/modules/agent/acp/profiles.route.ts
index cf06c373d..9e4fe6d3d 100644
--- a/apps/server/src/modules/agent/acp/profiles.route.ts
+++ b/apps/server/src/modules/agent/acp/profiles.route.ts
@@ -29,7 +29,6 @@ import {
   getAgentProfileRegistry,
   getAgentletGateway,
   getDaemonSupervisor,
-  getSupervisedAgentletId,
 } from '@agenetes/agentlet-host';
 
 import {
@@ -50,6 +49,7 @@ import {
   initializeAgentDefaults,
 } from '../agent-defaults.js';
 
+import type { AgentletConnection } from '@agenetes/agentlet-host';
 import type {
   AcpProfileMutationResponse,
   AcpProfilesListResponse,
@@ -68,6 +68,16 @@ function denyRemote(request: FastifyRequest, reply: FastifyReply): boolean {
   return true;
 }
 
+function getConnectedAgentlets(): AgentletConnection[] {
+  return getAgentletGateway()?.getAgentlets({ status: 'connected' }) ?? [];
+}
+
+function isAgentletConnected(agentletId: string): boolean {
+  return getConnectedAgentlets().some(
+    (connection) => connection.agentletId === agentletId,
+  );
+}
+
 async function validateHarnessLaunch(
   launch: AgentProfileView['launch'],
   agentletId: string,
@@ -146,10 +156,16 @@ const acpProfilesRoutes: FastifyPluginAsync = async (app) => {
       try {
         const gateway = getAgentletGateway();
         if (!gateway) throw new Error('Agentlet Gateway is not ready');
-        return await gateway.buildHarnessLaunch(
-          profile?.agentletId ?? getSupervisedAgentletId(),
-          { launch: parsed.data.launch },
-        );
+        const agentletId = profile?.agentletId ?? parsed.data.agentletId;
+        if (!agentletId || !isAgentletConnected(agentletId)) {
+          return reply.status(409).send({
+            code: 'agentlet_unavailable',
+            message: 'The selected Agentlet is not connected.',
+          });
+        }
+        return await gateway.buildHarnessLaunch(agentletId, {
+          launch: parsed.data.launch,
+        });
       } catch (error) {
         request.log.warn({ err: error }, 'Profile launch preview failed');
         return reply.status(503).send({
@@ -172,9 +188,46 @@ const acpProfilesRoutes: FastifyPluginAsync = async (app) => {
           code: 'profile_registry_unavailable',
         });
       }
+      const profiles = registry.listProfiles();
+      const connected = getConnectedAgentlets();
+      const connectedIds = new Set(
+        connected.map((connection) => connection.agentletId),
+      );
+      const profileCounts = new Map<string, number>();
+      for (const profile of profiles) {
+        profileCounts.set(
+          profile.agentletId,
+          (profileCounts.get(profile.agentletId) ?? 0) + 1,
+        );
+      }
+      const connectedDevices = connected
+        .map((connection) => ({
+          agentletId: connection.agentletId,
+          ...(connection.agentletProfile?.machine?.hostname
+            ? { hostname: connection.agentletProfile.machine.hostname }
+            : {}),
+          ...(connection.agentletProfile?.machine?.platform
+            ? { platform: connection.agentletProfile.machine.platform }
+            : {}),
+          ...(connection.agentletProfile?.machine?.arch
+            ? { arch: connection.agentletProfile.machine.arch }
+            : {}),
+          version: connection.agentletProfile?.bridge.version ?? 'unknown',
+          connectedAt: connection.connectedAt.toISOString(),
+          profileCount: profileCounts.get(connection.agentletId) ?? 0,
+        }))
+        .sort(
+          (left, right) =>
+            (left.hostname ?? left.agentletId).localeCompare(
+              right.hostname ?? right.agentletId,
+            ) || left.agentletId.localeCompare(right.agentletId),
+        );
       return {
-        profiles: registry.listProfiles(),
-        selectableProfileIds: registry.listSelectableProfileIds(),
+        profiles,
+        selectableProfileIds: profiles
+          .filter((profile) => connectedIds.has(profile.agentletId))
+          .map((profile) => profile.id),
+        connectedDevices,
         agentlet: getDaemonSupervisor().getStatus(),
         agentDefaults: getAgentDefaults(),
       };
@@ -206,7 +259,13 @@ const acpProfilesRoutes: FastifyPluginAsync = async (app) => {
           code: 'profile_registry_unavailable',
         });
       }
-      const agentletId = getSupervisedAgentletId();
+      const agentletId = parsed.data.agentletId;
+      if (!isAgentletConnected(agentletId)) {
+        return reply.status(409).send({
+          code: 'agentlet_unavailable',
+          message: 'The selected Agentlet is not connected.',
+        });
+      }
       const launch = parsed.data.launch;
       if (!(await validateHarnessLaunch(launch, agentletId, request, reply)))
         return;
diff --git a/apps/server/src/modules/agent/acp/service.ts b/apps/server/src/modules/agent/acp/service.ts
index 24d5fae3f..62a6d0194 100644
--- a/apps/server/src/modules/agent/acp/service.ts
+++ b/apps/server/src/modules/agent/acp/service.ts
@@ -22,10 +22,8 @@
 
 import { randomUUID } from 'node:crypto';
 
-import {
-  getAgentProfileRegistry,
-  getSupervisedAgentletId,
-} from '@agenetes/agentlet-host';
+import { AcpServiceError } from '@agenetes/acp-driver';
+import { getAgentProfileRegistry } from '@agenetes/agentlet-host';
 
 import { renderExternalAgentInputs } from './preprocessor.js';
 import { getProfileSessionPreferences } from './profile-session-preferences.js';
@@ -183,18 +181,18 @@ export function buildAcpWorkloadSpec(
   const { binding, threadId } = opts;
   const canvasId = opts.canvasId ?? '';
   const profile = resolveProfileSnapshot(binding.profileId);
-  let agentletId: string;
-  let cwd: string | undefined;
-  let recipe: AcpBindingRecipe | null;
-  if (profile) {
-    agentletId = profile.agentletId;
-    cwd = profile.workingDirPath;
-    recipe = recipeFromProfileSnapshot(profile, binding.alias);
-  } else {
-    agentletId = getSupervisedAgentletId();
-    cwd = opts.cwd;
-    recipe = resolveBindingRecipe(binding.profileId);
+  if (!profile) {
+    throw new AcpServiceError(
+      'profile_missing',
+      `Agent Profile '${binding.profileId}' is unavailable.`,
+    );
   }
+  const agentletId = profile.agentletId;
+  let cwd: string | undefined = profile.workingDirPath;
+  let recipe: AcpBindingRecipe | null = recipeFromProfileSnapshot(
+    profile,
+    binding.alias,
+  );
 
   const workingDirPath = opts.launchOverrides?.workingDirPath;
   cwd = workingDirPath ?? cwd;
diff --git a/apps/server/src/modules/agent/acp/service.workload-spec.test.ts b/apps/server/src/modules/agent/acp/service.workload-spec.test.ts
index 732e764eb..0434f5611 100644
--- a/apps/server/src/modules/agent/acp/service.workload-spec.test.ts
+++ b/apps/server/src/modules/agent/acp/service.workload-spec.test.ts
@@ -20,7 +20,6 @@ vi.mock('@agenetes/agentlet-host', () => ({
   getAgentProfileRegistry: () => ({
     getProfile: () => mocks.profile,
   }),
-  getSupervisedAgentletId: () => 'supervised-agentlet',
 }));
 
 vi.mock('../agenetes/drivers.js', () => ({
@@ -137,4 +136,14 @@ describe('buildAcpWorkloadSpec', () => {
       'Node constraints',
     ]);
   });
+
+  it('rejects a missing Profile instead of inventing a placement', () => {
+    expect(() =>
+      buildAcpWorkloadSpec({
+        binding: { profileId: 'missing', alias: 'Missing' },
+        threadId: 'thread-a',
+        canvasId: 'canvas-a',
+      }),
+    ).toThrow("Agent Profile 'missing' is unavailable.");
+  });
 });
diff --git a/apps/server/src/modules/agent/acp/threads.route.cached-meta.test.ts b/apps/server/src/modules/agent/acp/threads.route.cached-meta.test.ts
index c8fdf0d8a..66dfbc803 100644
--- a/apps/server/src/modules/agent/acp/threads.route.cached-meta.test.ts
+++ b/apps/server/src/modules/agent/acp/threads.route.cached-meta.test.ts
@@ -29,10 +29,6 @@ vi.mock('@agenetes/acp-driver', () => ({
   },
 }));
 
-vi.mock('@agenetes/agentlet-host', () => ({
-  getSupervisedAgentletId: () => 'agentlet-supervised',
-}));
-
 vi.mock('./external-agent-realization.js', () => ({
   externalAgentRealization: { realize: vi.fn(), ensureSession: vi.fn() },
   realizationHttpError: () => ({
@@ -139,7 +135,7 @@ describe('ACP cached-meta across awaited persistence', () => {
     });
   });
 
-  it('falls back to the supervised agentlet for a thread with no record', async () => {
+  it('does not invent a placement for a thread with no record', async () => {
     mocks.live.set('agentlet-supervised\u0000thread-1', {
       availableCommands: [],
       commandsUpdatedAt: 3,
@@ -160,11 +156,7 @@ describe('ACP cached-meta across awaited persistence', () => {
       url: CACHED_META_URL,
     });
 
-    expect(response.json()).toMatchObject({
-      source: 'thread',
-      commandsUpdatedAt: 3,
-      sessionMeta: { updatedAt: 4 },
-    });
+    expect(response.json()).toMatchObject({ source: 'none' });
   });
 
   it('answers a dormant thread from the metadata its record kept', async () => {
diff --git a/apps/server/src/modules/agent/acp/threads.route.test.ts b/apps/server/src/modules/agent/acp/threads.route.test.ts
index 0a1f91c1b..4f9549346 100644
--- a/apps/server/src/modules/agent/acp/threads.route.test.ts
+++ b/apps/server/src/modules/agent/acp/threads.route.test.ts
@@ -19,10 +19,6 @@ vi.mock('@agenetes/acp-driver', () => ({
   acpSessionRegistry: { get: () => mocks.live },
 }));
 
-vi.mock('@agenetes/agentlet-host', () => ({
-  getSupervisedAgentletId: () => 'agentlet-1',
-}));
-
 vi.mock('./external-agent-realization.js', () => ({
   externalAgentRealization: {
     realize: mocks.realize,
diff --git a/apps/server/src/modules/agent/acp/threads.route.ts b/apps/server/src/modules/agent/acp/threads.route.ts
index 58947fc60..df778ecb0 100644
--- a/apps/server/src/modules/agent/acp/threads.route.ts
+++ b/apps/server/src/modules/agent/acp/threads.route.ts
@@ -2,7 +2,6 @@
 // Licensed under the MIT license.
 
 import { acpSessionRegistry } from '@agenetes/acp-driver';
-import { getSupervisedAgentletId } from '@agenetes/agentlet-host';
 
 import {
   acpPermissionDecisionSchema,
@@ -140,7 +139,7 @@ export async function awaitSchemaQuiescence(
 async function resolveThreadAgentletId(
   threadId: string,
   canvasId?: string,
-): Promise<string> {
+): Promise<string | undefined> {
   if (canvasId) {
     const record = await agenetes.record(
       canvasAcpNamespace(canvasId),
@@ -155,7 +154,7 @@ async function resolveThreadAgentletId(
       return (driverSpec as { agentletId: string }).agentletId;
     }
   }
-  return getSupervisedAgentletId();
+  return undefined;
 }
 
 /**
@@ -285,7 +284,9 @@ const acpThreadsRoutes: FastifyPluginAsync = async (app) => {
     }
     const { canvasId, profileId } = parsed.data;
     const agentletId = await resolveThreadAgentletId(threadId, canvasId);
-    const live = acpSessionRegistry.get(agentletId, threadId);
+    const live = agentletId
+      ? acpSessionRegistry.get(agentletId, threadId)
+      : undefined;
     if (live) {
       return {
         source: 'thread',
diff --git a/apps/server/src/modules/agent/selectable-agent-profile.test.ts b/apps/server/src/modules/agent/selectable-agent-profile.test.ts
index d2976c00e..0f649404f 100644
--- a/apps/server/src/modules/agent/selectable-agent-profile.test.ts
+++ b/apps/server/src/modules/agent/selectable-agent-profile.test.ts
@@ -1,13 +1,34 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT license.
 
-import { describe, expect, it } from 'vitest';
+import { afterEach, describe, expect, it, vi } from 'vitest';
+
+const host = vi.hoisted(() => ({
+  profiles: [] as Array<{ id: string; alias: string; agentletId: string }>,
+  connectedIds: [] as string[],
+}));
+
+vi.mock('@agenetes/agentlet-host', () => ({
+  getAgentProfileRegistry: () => ({
+    getProfile: (profileId: string) =>
+      host.profiles.find((profile) => profile.id === profileId),
+    listProfiles: () => host.profiles,
+  }),
+  getAgentletGateway: () => ({
+    getAgentlets: () => host.connectedIds.map((agentletId) => ({ agentletId })),
+  }),
+}));
 
 import {
   listAvailableAgentProfiles,
   requireAvailableAgentProfile,
 } from './selectable-agent-profile.js';
 
+afterEach(() => {
+  host.profiles = [];
+  host.connectedIds = [];
+});
+
 describe('listAvailableAgentProfiles', () => {
   it('prepends Huabu and projects available Profile identities', () => {
     const profiles = new Map([
@@ -41,6 +62,19 @@ describe('listAvailableAgentProfiles', () => {
     ]);
   });
 
+  it('projects only Profiles on currently connected Agentlets by default', () => {
+    host.profiles = [
+      { id: 'online', alias: 'Online', agentletId: 'device-a' },
+      { id: 'offline', alias: 'Offline', agentletId: 'device-b' },
+    ];
+    host.connectedIds = ['device-a'];
+
+    expect(listAvailableAgentProfiles()).toEqual([
+      { id: 'huabu', alias: 'Built-In Pi' },
+      { id: 'online', alias: 'Online', default: true },
+    ]);
+  });
+
   it('accepts the Huabu Profile without an external registry', () => {
     expect(() => requireAvailableAgentProfile('huabu', null)).not.toThrow();
   });
diff --git a/apps/server/src/modules/agent/selectable-agent-profile.ts b/apps/server/src/modules/agent/selectable-agent-profile.ts
index aabc27e89..8b69df24e 100644
--- a/apps/server/src/modules/agent/selectable-agent-profile.ts
+++ b/apps/server/src/modules/agent/selectable-agent-profile.ts
@@ -1,7 +1,10 @@
 // Copyright (c) Microsoft Corporation.
 // Licensed under the MIT license.
 
-import { getAgentProfileRegistry } from '@agenetes/agentlet-host';
+import {
+  getAgentProfileRegistry,
+  getAgentletGateway,
+} from '@agenetes/agentlet-host';
 
 import { HUABU_AGENT_PROFILE_ID } from '@huabu/shared';
 
@@ -18,6 +21,25 @@ interface AgentProfileRegistryPort {
   listSelectableProfileIds(): string[];
 }
 
+function getConnectedProfileRegistry(): AgentProfileRegistryPort | null {
+  const registry = getAgentProfileRegistry();
+  if (!registry) return null;
+  return {
+    getProfile: (profileId) => registry.getProfile(profileId),
+    listSelectableProfileIds: () => {
+      const connectedIds = new Set(
+        (getAgentletGateway()?.getAgentlets({ status: 'connected' }) ?? []).map(
+          (connection) => connection.agentletId,
+        ),
+      );
+      return registry
+        .listProfiles()
+        .filter((profile) => connectedIds.has(profile.agentletId))
+        .map((profile) => profile.id);
+    },
+  };
+}
+
 export interface AvailableAgentProfileSummary {
   id: string;
   alias: string;
@@ -36,7 +58,7 @@ export class SelectableAgentProfileError extends Error {
 
 export function requireSelectableAgentProfile(
   profileId: string,
-  registry: AgentProfileRegistryPort | null = getAgentProfileRegistry(),
+  registry: AgentProfileRegistryPort | null = getConnectedProfileRegistry(),
 ): SelectableAgentProfile {
   if (!registry) {
     throw new SelectableAgentProfileError(
@@ -60,20 +82,20 @@ export function requireSelectableAgentProfile(
 
 export function requireAvailableAgentProfile(
   profileId: string,
-  registry: AgentProfileRegistryPort | null = getAgentProfileRegistry(),
+  registry: AgentProfileRegistryPort | null = getConnectedProfileRegistry(),
 ): void {
   if (profileId === HUABU_AGENT_PROFILE_ID) return;
   requireSelectableAgentProfile(profileId, registry);
 }
 
 export function getFirstSelectableAgentProfileId(
-  registry: AgentProfileRegistryPort | null = getAgentProfileRegistry(),
+  registry: AgentProfileRegistryPort | null = getConnectedProfileRegistry(),
 ): string | null {
   return registry?.listSelectableProfileIds()[0] ?? null;
 }
 
 export function listAvailableAgentProfiles(
-  registry: AgentProfileRegistryPort | null = getAgentProfileRegistry(),
+  registry: AgentProfileRegistryPort | null = getConnectedProfileRegistry(),
 ): AvailableAgentProfileSummary[] {
   const defaultProfileId = getFirstSelectableAgentProfileId(registry);
   const huabu = {
diff --git a/apps/web/src/api/_routes.ts b/apps/web/src/api/_routes.ts
index b14e52c9b..2cabc6501 100644
--- a/apps/web/src/api/_routes.ts
+++ b/apps/web/src/api/_routes.ts
@@ -149,8 +149,12 @@ export const routes = {
   agentChangeReviewConfig: '/agent-change-review/config',
 
   // ── ACP (external agent bridge) ───────────────────────────────────
-  acpAgentCli: (profileId?: string) =>
-    `/acp/agent-cli${profileId ? `?profileId=${enc(profileId)}` : ''}`,
+  acpAgentCli: (target: { profileId?: string; agentletId?: string }) => {
+    const params = target.profileId
+      ? `profileId=${enc(target.profileId)}`
+      : `agentletId=${enc(target.agentletId ?? '')}`;
+    return `/acp/agent-cli?${params}`;
+  },
   // Profiles (loopback-only) — user-managed spawn recipes.
   acpProfiles: '/acp/profiles',
   acpProfileLaunchPreview: '/acp/profile-launch-preview',
diff --git a/apps/web/src/api/acp.test.ts b/apps/web/src/api/acp.test.ts
index 26697c41d..a4841ea6d 100644
--- a/apps/web/src/api/acp.test.ts
+++ b/apps/web/src/api/acp.test.ts
@@ -18,19 +18,19 @@ describe('ACP Profile editing API', () => {
   it('routes discovery to the saved Profile and encodes its identity', async () => {
     const fetch = vi.fn().mockResolvedValue(new Response('{"agents":[]}'));
     vi.stubGlobal('fetch', fetch);
-    await listAcpAgentClis('remote/#1');
+    await listAcpAgentClis({ profileId: 'remote/#1' });
     expect(fetch).toHaveBeenCalledWith(
       expect.stringMatching(/\/api\/acp\/agent-cli\?profileId=remote%2F%231$/),
       expect.any(Object),
     );
   });
 
-  it('uses supervised-daemon discovery for creation', async () => {
+  it('routes creation discovery to the selected Agentlet', async () => {
     const fetch = vi.fn().mockResolvedValue(new Response('{"agents":[]}'));
     vi.stubGlobal('fetch', fetch);
-    await listAcpAgentClis();
+    await listAcpAgentClis({ agentletId: 'device/#1' });
     expect(fetch).toHaveBeenCalledWith(
-      expect.stringMatching(/\/api\/acp\/agent-cli$/),
+      expect.stringMatching(/\/api\/acp\/agent-cli\?agentletId=device%2F%231$/),
       expect.any(Object),
     );
   });
diff --git a/apps/web/src/api/acp.ts b/apps/web/src/api/acp.ts
index 4b56cb1c9..f8965f44f 100644
--- a/apps/web/src/api/acp.ts
+++ b/apps/web/src/api/acp.ts
@@ -29,6 +29,7 @@ import { routes } from './_routes';
 
 import type {
   AcpAgentCliListResponse,
+  AcpAgentCliQuery,
   AcpAgentletStatus,
   AcpAgentletStatusResponse,
   AcpPermissionDecisionRequest,
@@ -55,6 +56,7 @@ import type {
 } from '@huabu/shared';
 
 export type {
+  AcpAgentCliQuery,
   AcpAgentCliInfo,
   AcpAgentCliListResponse,
   AcpAgentProfile,
@@ -84,6 +86,7 @@ export type {
   ConnectionTokenConfig,
   ConnectionTokenUpdate,
   AgentletConnectionCommandResponse,
+  ConnectedAgentletDevice,
   WarmAcpSessionRequest,
   WarmAcpSessionResponse,
 } from '@huabu/shared';
@@ -91,12 +94,12 @@ export type {
 // ── Agent CLI detection ──────────────────────────────────────────────
 
 /**
- * Read the supervised daemon's catalogue, or the saved Profile's target daemon.
+ * Read the explicitly selected Agentlet's catalogue.
  */
 export async function listAcpAgentClis(
-  profileId?: string,
+  target: AcpAgentCliQuery,
 ): Promise<AcpAgentCliListResponse> {
-  return apiFetch<AcpAgentCliListResponse>(routes.acpAgentCli(profileId), {
+  return apiFetch<AcpAgentCliListResponse>(routes.acpAgentCli(target), {
     fallbackMessage: 'Failed to detect installed agent CLIs',
   });
 }
@@ -111,7 +114,7 @@ export async function listAcpProfiles(): Promise<AcpProfilesListResponse> {
 }
 
 /**
- * Create a command Profile on the local agentlet. The server allocates its id.
+ * Create a command Profile on its explicitly selected Agentlet.
  */
 export async function createAcpProfile(
   payload: CreateAcpProfileBody,
diff --git a/apps/web/src/components/Settings/agent-profiles/AgentProfileEditor.test.tsx b/apps/web/src/components/Settings/agent-profiles/AgentProfileEditor.test.tsx
index 0140a3aaf..fc388e428 100644
--- a/apps/web/src/components/Settings/agent-profiles/AgentProfileEditor.test.tsx
+++ b/apps/web/src/components/Settings/agent-profiles/AgentProfileEditor.test.tsx
@@ -62,12 +62,18 @@ vi.mock('@/components/Common/Select', () => ({
     value,
     options,
     onChange,
+    ariaLabel,
   }: {
     value: string;
     options: { value: string; label: string; disabled?: boolean }[];
     onChange: (value: string) => void;
+    ariaLabel?: string;
   }) => (
-    <select value={value} onChange={(event) => onChange(event.target.value)}>
+    <select
+      aria-label={ariaLabel}
+      value={value}
+      onChange={(event) => onChange(event.target.value)}
+    >
       <option value="">Loading</option>
       {options.map((option) => (
         <option
@@ -156,6 +162,19 @@ function renderEditor(
           : ({ mode: 'create' } as const))}
         detectedClis={clis}
         detectionLoaded={loaded}
+        connectedDevices={[
+          {
+            agentletId: editing?.agentletId ?? 'device-1',
+            hostname: 'Test device',
+            platform: 'linux',
+            arch: 'x64',
+            version: '1.0.0',
+            connectedAt: '2026-01-01T00:00:00.000Z',
+            profileCount: 0,
+          },
+        ]}
+        agentletId={editing?.agentletId ?? 'device-1'}
+        onAgentletChange={vi.fn()}
         onClose={onClose}
         onSaved={onSaved}
       />,
@@ -188,7 +207,9 @@ async function settlePreview() {
   });
 }
 function chooseCustom() {
-  const select = container?.querySelector('select');
+  const select = container?.querySelector<HTMLSelectElement>(
+    'select[aria-label="settings.agent"]',
+  );
   act(() => {
     if (select) select.value = 'custom';
     select?.dispatchEvent(new Event('change', { bubbles: true }));
@@ -268,7 +289,9 @@ describe('AgentProfileEditor', () => {
 
   it('lists known wrappers with unsupported choices disabled and one Custom option', () => {
     renderEditor();
-    const select = container?.querySelector('select');
+    const select = container?.querySelector<HTMLSelectElement>(
+      'select[aria-label="settings.agent"]',
+    );
     expect(select?.value).toBe('copilot');
     expect(
       [...(select?.options ?? [])].filter(
@@ -293,6 +316,7 @@ describe('AgentProfileEditor', () => {
     expect(saveButton()?.disabled).toBe(true);
     await settlePreview();
     expect(api.preview).toHaveBeenCalledWith({
+      agentletId: 'device-1',
       launch: {
         kind: 'acp-harness',
         harnessId: 'copilot',
@@ -308,6 +332,7 @@ describe('AgentProfileEditor', () => {
     await act(async () => saveButton()?.click());
     expect(api.create).toHaveBeenCalledWith({
       alias: 'GitHub Copilot (project)',
+      agentletId: 'device-1',
       workingDirPath: 'C:\\work\\project',
       launch: {
         kind: 'acp-harness',
@@ -382,7 +407,11 @@ describe('AgentProfileEditor', () => {
       undefined,
       agents.map((agent) => ({ ...agent, launchPreviewVersion: undefined })),
     );
-    expect(container?.querySelector('select')?.value).toBe('custom');
+    expect(
+      container?.querySelector<HTMLSelectElement>(
+        'select[aria-label="settings.agent"]',
+      )?.value,
+    ).toBe('custom');
     expect(container?.textContent).toContain(
       'settings.structuredLaunchUnavailable',
     );
diff --git a/apps/web/src/components/Settings/agent-profiles/AgentProfileEditor.tsx b/apps/web/src/components/Settings/agent-profiles/AgentProfileEditor.tsx
index 9a7abcdb1..6ffbc3816 100644
--- a/apps/web/src/components/Settings/agent-profiles/AgentProfileEditor.tsx
+++ b/apps/web/src/components/Settings/agent-profiles/AgentProfileEditor.tsx
@@ -3,11 +3,18 @@
 
 import { CommandProfileForm } from './CommandProfileForm';
 
-import type { AcpAgentCliInfo, AgentProfileView } from '@huabu/shared';
+import type {
+  AcpAgentCliInfo,
+  AgentProfileView,
+  ConnectedAgentletDevice,
+} from '@huabu/shared';
 
 type AgentProfileEditorProps = {
   detectedClis: AcpAgentCliInfo[];
   detectionLoaded: boolean;
+  connectedDevices: ConnectedAgentletDevice[];
+  agentletId: string;
+  onAgentletChange: (agentletId: string) => void;
   onClose: () => void;
   onSaved: () => Promise<void>;
 } & ({ mode: 'create' } | { mode: 'edit-command'; profile: AgentProfileView });
@@ -23,6 +30,9 @@ export function AgentProfileEditor(props: AgentProfileEditorProps) {
       editing={props.mode === 'create' ? null : props.profile}
       detectedClis={props.detectedClis}
       detectionLoaded={props.detectionLoaded}
+      connectedDevices={props.connectedDevices}
+      agentletId={props.agentletId}
+      onAgentletChange={props.onAgentletChange}
       onClose={props.onClose}
       onSaved={props.onSaved}
     />
diff --git a/apps/web/src/components/Settings/agent-profiles/CommandProfileForm.tsx b/apps/web/src/components/Settings/agent-profiles/CommandProfileForm.tsx
index 7955e606f..752e2d8f2 100644
--- a/apps/web/src/components/Settings/agent-profiles/CommandProfileForm.tsx
+++ b/apps/web/src/components/Settings/agent-profiles/CommandProfileForm.tsx
@@ -25,12 +25,19 @@ import { ProfileEditActions } from './ProfileEditActions';
 import { ReadOnlyField } from './ReadOnlyField';
 import { useProfileLaunchPreview } from './useProfileLaunchPreview';
 
-import type { AcpAgentCliInfo, AgentProfileView } from '@huabu/shared';
+import type {
+  AcpAgentCliInfo,
+  AgentProfileView,
+  ConnectedAgentletDevice,
+} from '@huabu/shared';
 
 interface CommandProfileFormProps {
   editing: AgentProfileView | null;
   detectedClis: AcpAgentCliInfo[];
   detectionLoaded: boolean;
+  connectedDevices: ConnectedAgentletDevice[];
+  agentletId: string;
+  onAgentletChange: (agentletId: string) => void;
   onClose: () => void;
   onSaved: () => Promise<void>;
 }
@@ -73,6 +80,9 @@ export function CommandProfileForm({
   editing,
   detectedClis,
   detectionLoaded,
+  connectedDevices,
+  agentletId,
+  onAgentletChange,
   onClose,
   onSaved,
 }: CommandProfileFormProps) {
@@ -156,7 +166,10 @@ export function CommandProfileForm({
           };
   const preview = useProfileLaunchPreview(
     !custom && structuredSupported
-      ? { launch, ...(editing ? { profileId: editing.id } : {}) }
+      ? {
+          launch,
+          ...(editing ? { profileId: editing.id } : { agentletId }),
+        }
       : null,
   );
   const executionChanged = launchChanged || cwdChanged;
@@ -169,7 +182,12 @@ export function CommandProfileForm({
           !preview.plan ||
           !!preview.error ||
           (launchChanged && !approvalSupported && !!editing)));
-  const saveDisabled = saving || !cliId || invalidExecution;
+  const saveDisabled =
+    saving ||
+    !cliId ||
+    !agentletId ||
+    (!editing && !connectedDevices.length) ||
+    invalidExecution;
   const knownControlsDisabled =
     saving || !structuredSupported || !!preview.error;
   const options = [
@@ -198,6 +216,7 @@ export function CommandProfileForm({
       } else {
         await createAcpProfile({
           alias: displayName.trim() || defaultName,
+          agentletId,
           workingDirPath: cwd.trim(),
           launch,
           metadata: { cliId },
@@ -226,6 +245,27 @@ export function CommandProfileForm({
 
   return (
     <div className="divide-edge-default flex flex-col divide-y">
+      <SettingRow title={t('settings.profileMachine')}>
+        <SettingControl>
+          {editing ? (
+            <ReadOnlyField value={editing.agentletId} mono />
+          ) : (
+            <Select
+              value={agentletId}
+              onChange={onAgentletChange}
+              options={connectedDevices.map((device) => ({
+                value: device.agentletId,
+                label: device.hostname ?? device.agentletId,
+                description: device.agentletId,
+              }))}
+              placeholder={t('settings.noConnectedDevices')}
+              ariaLabel={t('settings.profileMachine')}
+              disabled={saving || connectedDevices.length === 0}
+              className="w-full"
+            />
+          )}
+        </SettingControl>
+      </SettingRow>
       <SettingRow title={t('settings.agent')}>
         <SettingControl>
           {editing ? (
@@ -246,13 +286,6 @@ export function CommandProfileForm({
           )}
         </SettingControl>
       </SettingRow>
-      {editing ? (
-        <SettingRow title={t('settings.profileMachine')}>
-          <SettingControl>
-            <ReadOnlyField value={editing.agentletId} mono />
-          </SettingControl>
-        </SettingRow>
-      ) : null}
       {custom ? (
         <SettingRow
           labelFor={commandId}
diff --git a/apps/web/src/components/Settings/agent-profiles/ExternalAgentsSettings.test.tsx b/apps/web/src/components/Settings/agent-profiles/ExternalAgentsSettings.test.tsx
index f7a321325..4a63c9ef1 100644
--- a/apps/web/src/components/Settings/agent-profiles/ExternalAgentsSettings.test.tsx
+++ b/apps/web/src/components/Settings/agent-profiles/ExternalAgentsSettings.test.tsx
@@ -141,11 +141,23 @@ beforeEach(() => {
   apiMocks.list.mockImplementation(async () => ({
     profiles: [...profiles],
     selectableProfileIds: [],
+    connectedDevices: [
+      {
+        agentletId: 'local',
+        hostname: 'Local machine',
+        platform: 'linux',
+        arch: 'x64',
+        version: '1.0.0',
+        connectedAt: '2026-01-01T00:00:00.000Z',
+        profileCount: 1,
+      },
+    ],
     agentlet: null,
   }));
   useAcpProfilesStore.setState({
     profiles: [],
     selectableProfileIds: [],
+    connectedDevices: [],
     agentlet: null,
     loaded: true,
     loading: false,
@@ -222,7 +234,9 @@ describe('ExternalAgentsSettings', () => {
     });
     await renderSettings();
     await click('settings.editProfile');
-    expect(apiMocks.detection).toHaveBeenLastCalledWith(true, profile.id);
+    expect(apiMocks.detection).toHaveBeenLastCalledWith(true, {
+      profileId: profile.id,
+    });
     input('input[aria-label="settings.displayName"]', 'Renamed');
     await click('settings.saveChanges');
 
diff --git a/apps/web/src/components/Settings/agent-profiles/ExternalAgentsSettings.tsx b/apps/web/src/components/Settings/agent-profiles/ExternalAgentsSettings.tsx
index 92f7ca0af..3ff6d1f34 100644
--- a/apps/web/src/components/Settings/agent-profiles/ExternalAgentsSettings.tsx
+++ b/apps/web/src/components/Settings/agent-profiles/ExternalAgentsSettings.tsx
@@ -30,7 +30,7 @@ import type { AgentIconValue } from '@/components/Common/AgentIcon';
 import type { AgentProfileView } from '@huabu/shared';
 
 type EditorState =
-  | { kind: 'create' }
+  | { kind: 'create'; agentletId: string }
   | { kind: 'edit-command'; profile: AgentProfileView };
 
 interface PendingDelete {
@@ -52,6 +52,12 @@ export function ExternalAgentsSettings({
 }: ExternalAgentsSettingsProps) {
   const { t } = useTranslation();
   const profiles = useAcpProfilesStore((state) => state.profiles);
+  const connectedDevices = useAcpProfilesStore(
+    (state) => state.connectedDevices,
+  );
+  const selectableProfileIds = useAcpProfilesStore(
+    (state) => state.selectableProfileIds,
+  );
   const loading = useAcpProfilesStore((state) => state.loading);
   const error = useAcpProfilesStore((state) => state.error);
   const agentlet = useAcpProfilesStore((state) => state.agentlet);
@@ -178,12 +184,20 @@ export function ExternalAgentsSettings({
     [],
   );
 
-  const needsCliNames = profiles.some(
-    (profile) => profile.launch.kind === 'acp-harness',
+  const catalogueProfile = profiles.find(
+    (profile) =>
+      profile.launch.kind === 'acp-harness' &&
+      selectableProfileIds.includes(profile.id),
   );
   const { detectedClis, loaded: detectionLoaded } = useDetectedClis(
-    needsCliNames || editor !== null,
-    editor?.kind === 'edit-command' ? editor.profile.id : undefined,
+    editor !== null || catalogueProfile !== undefined,
+    editor?.kind === 'edit-command'
+      ? { profileId: editor.profile.id }
+      : editor?.kind === 'create'
+        ? { agentletId: editor.agentletId }
+        : catalogueProfile
+          ? { profileId: catalogueProfile.id }
+          : { agentletId: '' },
   );
 
   const saveIcon = useCallback(
@@ -214,15 +228,18 @@ export function ExternalAgentsSettings({
       profile.launch.kind === 'acp-harness'
         ? profile.launch.harnessId
         : 'custom';
-    if (!cliId || cliId === 'custom') {
-      return [
-        t('settings.agentCustomBadge'),
-        profile.launch.kind === 'acp-command'
-          ? profile.launch.command
-          : profile.launch.harnessId,
-      ].join(' · ');
-    }
-    return detectedClis.find((cli) => cli.id === cliId)?.displayName ?? cliId;
+    const description =
+      !cliId || cliId === 'custom'
+        ? [
+            t('settings.agentCustomBadge'),
+            profile.launch.kind === 'acp-command'
+              ? profile.launch.command
+              : profile.launch.harnessId,
+          ].join(' · ')
+        : (detectedClis.find((cli) => cli.id === cliId)?.displayName ?? cliId);
+    return selectableProfileIds.includes(profile.id)
+      ? description
+      : `${description} · ${t('settings.agentUnavailable')}`;
   };
 
   const handleRestart = useCallback(async () => {
@@ -281,6 +298,19 @@ export function ExternalAgentsSettings({
                       })}
                   detectedClis={detectedClis}
                   detectionLoaded={detectionLoaded}
+                  connectedDevices={connectedDevices}
+                  agentletId={
+                    editor.kind === 'create'
+                      ? editor.agentletId
+                      : editor.profile.agentletId
+                  }
+                  onAgentletChange={(agentletId) =>
+                    setEditor((current) =>
+                      current?.kind === 'create'
+                        ? { ...current, agentletId }
+                        : current,
+                    )
+                  }
                   onClose={closeEditor}
                   onSaved={refresh}
                 />
@@ -290,6 +320,36 @@ export function ExternalAgentsSettings({
           </div>
         ) : (
           <div key="list" ref={activeViewRef}>
+            <SettingSection title={t('settings.connectedDevices')}>
+              {connectedDevices.length === 0 ? (
+                <SettingRow
+                  title={t('settings.noConnectedDevices')}
+                  description={t('settings.noConnectedDevicesDescription')}
+                >
+                  <span />
+                </SettingRow>
+              ) : (
+                connectedDevices.map((device) => (
+                  <SettingRow
+                    key={device.agentletId}
+                    title={device.hostname ?? device.agentletId}
+                    description={[
+                      [device.platform, device.arch].filter(Boolean).join(' '),
+                      t('settings.deviceProfileCount', {
+                        count: device.profileCount,
+                      }),
+                      device.agentletId,
+                    ]
+                      .filter(Boolean)
+                      .join(' · ')}
+                  >
+                    <span className="text-fg-subtle text-xs">
+                      {device.version}
+                    </span>
+                  </SettingRow>
+                ))
+              )}
+            </SettingSection>
             <SettingSection title={t('settings.agentProfiles')}>
               {loading ? (
                 <SettingRow title={t('settings.loadingAgents')}>
@@ -359,7 +419,12 @@ export function ExternalAgentsSettings({
                       size="sm"
                       ref={restoreTriggerFocus('create')}
                       data-editor-trigger="create"
-                      onClick={() => openEditor({ kind: 'create' }, 'create')}
+                      onClick={() => {
+                        const agentletId = connectedDevices[0]?.agentletId;
+                        if (agentletId)
+                          openEditor({ kind: 'create', agentletId }, 'create');
+                      }}
+                      disabled={connectedDevices.length === 0}
                     >
                       <Plus size={12} />
                       <span>{t('settings.addAgent')}</span>
diff --git a/apps/web/src/components/Settings/agent-profiles/useDetectedClis.test.tsx b/apps/web/src/components/Settings/agent-profiles/useDetectedClis.test.tsx
index 91a73aa06..b58d816b8 100644
--- a/apps/web/src/components/Settings/agent-profiles/useDetectedClis.test.tsx
+++ b/apps/web/src/components/Settings/agent-profiles/useDetectedClis.test.tsx
@@ -40,7 +40,10 @@ function Harness({
   enabled: boolean;
   profileId?: string;
 }) {
-  const { detectedClis, loaded } = useDetectedClis(enabled, profileId);
+  const { detectedClis, loaded } = useDetectedClis(
+    enabled,
+    profileId ? { profileId } : { agentletId: 'local-device' },
+  );
   return (
     <span>
       {loaded ? 'loaded' : 'idle'}:{detectedClis.length}
@@ -166,14 +169,12 @@ describe('useDetectedClis', () => {
     );
     await act(async () => resolveOld?.({ agents: [detectedAgent] }));
 
-    expect(apiMocks.listAgentClis).toHaveBeenNthCalledWith(
-      1,
-      'machine-a-profile',
-    );
-    expect(apiMocks.listAgentClis).toHaveBeenNthCalledWith(
-      2,
-      'machine-b-profile',
-    );
+    expect(apiMocks.listAgentClis).toHaveBeenNthCalledWith(1, {
+      profileId: 'machine-a-profile',
+    });
+    expect(apiMocks.listAgentClis).toHaveBeenNthCalledWith(2, {
+      profileId: 'machine-b-profile',
+    });
     expect(container.textContent).toBe('loaded:0');
   });
 
@@ -190,7 +191,9 @@ describe('useDetectedClis', () => {
       root?.render(<Harness enabled profileId="remote-profile" />),
     );
     expect(container.textContent).toBe('loaded:0');
-    expect(apiMocks.listAgentClis).toHaveBeenLastCalledWith('remote-profile');
+    expect(apiMocks.listAgentClis).toHaveBeenLastCalledWith({
+      profileId: 'remote-profile',
+    });
     expect(apiMocks.toast).toHaveBeenCalledWith('Target offline', {
       tone: 'danger',
     });
diff --git a/apps/web/src/components/Settings/agent-profiles/useDetectedClis.ts b/apps/web/src/components/Settings/agent-profiles/useDetectedClis.ts
index 1d4074aef..89c82667e 100644
--- a/apps/web/src/components/Settings/agent-profiles/useDetectedClis.ts
+++ b/apps/web/src/components/Settings/agent-profiles/useDetectedClis.ts
@@ -7,41 +7,42 @@ import { useTranslation } from 'react-i18next';
 import { listAcpAgentClis } from '@/api/acp';
 import { toast } from '@/components/Common/Toast';
 
-import type { AcpAgentCliInfo } from '@huabu/shared';
+import type { AcpAgentCliInfo, AcpAgentCliQuery } from '@huabu/shared';
 
 /** Reads the daemon's catalogue for Settings without a browser discovery cache. */
 export function useDetectedClis(
   enabled = true,
-  profileId?: string,
+  target: AcpAgentCliQuery,
 ): {
   detectedClis: AcpAgentCliInfo[];
   loaded: boolean;
 } {
   const { t } = useTranslation();
   const [snapshot, setSnapshot] = useState<{
-    profileId?: string;
+    key: string;
     detectedClis: AcpAgentCliInfo[];
     loaded: boolean;
-  }>({ profileId, detectedClis: [], loaded: false });
+  }>({ key: JSON.stringify(target), detectedClis: [], loaded: false });
+  const key = JSON.stringify(target);
 
   useEffect(() => {
     if (!enabled) return;
     let generation = 0;
     const load = async () => {
       const current = ++generation;
-      setSnapshot({ profileId, loaded: false, detectedClis: [] });
+      setSnapshot({ key, loaded: false, detectedClis: [] });
       try {
-        const response = await listAcpAgentClis(profileId);
+        const response = await listAcpAgentClis(target);
         if (current === generation) {
           setSnapshot({
-            profileId,
+            key,
             loaded: true,
             detectedClis: response.agents,
           });
         }
       } catch (error) {
         if (current === generation) {
-          setSnapshot({ profileId, loaded: true, detectedClis: [] });
+          setSnapshot({ key, loaded: true, detectedClis: [] });
           toast(
             error instanceof Error
               ? error.message
@@ -58,9 +59,9 @@ export function useDetectedClis(
       generation++;
       window.removeEventListener('workspace-changed', handler);
     };
-  }, [enabled, profileId, t]);
+  }, [enabled, key, t]);
 
-  return snapshot.profileId === profileId
+  return snapshot.key === key
     ? { detectedClis: snapshot.detectedClis, loaded: snapshot.loaded }
     : { detectedClis: [], loaded: false };
 }
diff --git a/apps/web/src/i18n/resources/en/common.json b/apps/web/src/i18n/resources/en/common.json
index 86ed9d305..074a8ffad 100644
--- a/apps/web/src/i18n/resources/en/common.json
+++ b/apps/web/src/i18n/resources/en/common.json
@@ -206,6 +206,12 @@
     "profileCreated": "Profile created",
     "profileUpdated": "Profile updated",
     "profileMachine": "Machine (fixed)",
+    "connectedDevices": "Connected devices",
+    "noConnectedDevices": "No Agentlet devices connected",
+    "noConnectedDevicesDescription": "Connect an Agentlet before creating a Profile.",
+    "deviceProfileCount_one": "{{count}} Profile",
+    "deviceProfileCount_other": "{{count}} Profiles",
+    "agentUnavailable": "Device unavailable",
     "profileLaunchPreviewHint": "Read-only launch plan built by the wrapper on the target machine. Previewing does not start an agent; environment values are not displayed.",
     "profilePreviewLoading": "Preparing launch preview…",
     "profilePreviewUnavailable": "Launch preview unavailable.",
diff --git a/apps/web/src/i18n/resources/zh-CN/common.json b/apps/web/src/i18n/resources/zh-CN/common.json
index 136696567..be029bcc0 100644
--- a/apps/web/src/i18n/resources/zh-CN/common.json
+++ b/apps/web/src/i18n/resources/zh-CN/common.json
@@ -206,6 +206,12 @@
     "profileCreated": "配置已创建",
     "profileUpdated": "配置已更新",
     "profileMachine": "机器（不可更改）",
+    "connectedDevices": "已连接设备",
+    "noConnectedDevices": "没有已连接的 Agentlet 设备",
+    "noConnectedDevicesDescription": "请先连接 Agentlet，再创建配置。",
+    "deviceProfileCount_one": "{{count}} 个配置",
+    "deviceProfileCount_other": "{{count}} 个配置",
+    "agentUnavailable": "设备不可用",
     "profileLaunchPreviewHint": "由目标机器上的封装器生成的只读启动计划。预览不会启动智能体，也不会显示环境变量的值。",
     "profilePreviewLoading": "正在生成启动预览…",
     "profilePreviewUnavailable": "启动预览不可用。",
diff --git a/apps/web/src/store/acpProfilesStore.test.ts b/apps/web/src/store/acpProfilesStore.test.ts
index ec5abeeb4..49932ec3e 100644
--- a/apps/web/src/store/acpProfilesStore.test.ts
+++ b/apps/web/src/store/acpProfilesStore.test.ts
@@ -36,6 +36,7 @@ const profile = {
 const snapshot = {
   profiles: [profile],
   selectableProfileIds: [profile.id],
+  connectedDevices: [],
   agentlet: null,
   agentDefaults: { profileId: 'huabu', functionalModel: 'utility-only' },
 };
@@ -61,6 +62,7 @@ beforeEach(() => {
     error: null,
     profiles: [profile],
     selectableProfileIds: [profile.id],
+    connectedDevices: [],
     agentDefaults: null,
     defaultsError: null,
     recentConversationProfileId: null,
diff --git a/apps/web/src/store/acpProfilesStore.ts b/apps/web/src/store/acpProfilesStore.ts
index 1da23dc0e..694e16c27 100644
--- a/apps/web/src/store/acpProfilesStore.ts
+++ b/apps/web/src/store/acpProfilesStore.ts
@@ -47,7 +47,11 @@ import { getAgentDefaults, updateAgentDefaults } from '@/api/agentDefaults';
 import { toast } from '@/components/Common/Toast';
 import { i18n } from '@/i18n';
 
-import type { AcpAgentletStatus, AgentProfileView } from '@/api/acp';
+import type {
+  AcpAgentletStatus,
+  AgentProfileView,
+  ConnectedAgentletDevice,
+} from '@/api/acp';
 import type {
   AgentBinding,
   AgentDefaults,
@@ -88,6 +92,8 @@ interface AcpProfilesState {
   profiles: AgentProfileView[];
   /** Profile ids that are currently runtime-ready and safe to select. */
   selectableProfileIds: string[];
+  /** Active Agentlet control connections, sorted by the server. */
+  connectedDevices: ConnectedAgentletDevice[];
   /** Latest agentlet snapshot. `null` until the first fetch resolves. */
   agentlet: AcpAgentletStatus | null;
   /** Absent on older servers; never infer a default from list ordering. */
@@ -121,6 +127,7 @@ interface AcpProfilesState {
 export const useAcpProfilesStore = create<AcpProfilesState>()((set, get) => ({
   profiles: [],
   selectableProfileIds: [],
+  connectedDevices: [],
   agentlet: null,
   agentDefaults: null,
   defaultsError: null,
@@ -229,6 +236,7 @@ export const useAcpProfilesStore = create<AcpProfilesState>()((set, get) => ({
         set({
           profiles: res.profiles,
           selectableProfileIds: res.selectableProfileIds,
+          connectedDevices: res.connectedDevices,
           agentlet: res.agentlet,
           ...(revision === defaultsRevision
             ? { agentDefaults: res.agentDefaults ?? null, defaultsError: null }
diff --git a/docs/architecture/agent-profiles.md b/docs/architecture/agent-profiles.md
index 915bb9df1..04c7fd28f 100644
--- a/docs/architecture/agent-profiles.md
+++ b/docs/architecture/agent-profiles.md
@@ -23,7 +23,9 @@ Automatic discovery requests workspace preparation. The daemon resolves its own
 
 Huabu subscribes to machine connection events, includes machines already connected at registration, and invalidates stale results on reconnect, disconnect, and shutdown. After each successful response it synchronously checks and creates automatic defaults through the registry. The check and commit contain no asynchronous gap.
 
-The Agentlet CLI defaults an omitted `--agentlet-id` to the machine hostname, so a copied connection command needs no identity argument for the common personal setup. Different hostnames may share the same Huabu connection token and connect concurrently. If an identity is already online, Gateway rejects the second live connection with guidance to retry using `--agentlet-id <unique-id>` instead of evicting the first machine; once the prior connection is disconnected, the same identity follows the normal reconnect path.
+The Agentlet CLI owns its default device identity. On first start it atomically creates `~/.agentlet/device.json` containing `{ "version": 1, "deviceId": "<uuid>" }`; later starts reuse that UUID, so identity survives daemon, Huabu, OS-session, binary, upgrade, and worktree restarts while the home directory remains. A malformed or unreadable identity file fails explicitly instead of rotating identity. `--agentlet-id` remains an advanced exact override and does not rewrite the persisted UUID. Hello metadata reports the real hostname, platform, and architecture separately for display; none of those fields participates in identity. Windows and WSL naturally receive distinct identities because they use separate home directories.
+
+Multiple Agentlets may share one Huabu connection token and connect concurrently. If an identity is already online, Gateway rejects the second live connection with guidance to retry using `--agentlet-id <unique-id>` instead of evicting the first device; once the prior connection is disconnected, the same identity follows the normal reconnect path. The embedded supervisor is special only as process-lifecycle infrastructure: it resolves, starts, restarts, stops, and diagnoses its child, but it neither assigns that Agentlet's identity nor acts as a placement default.
 
 ## Profile identity and customization
 
@@ -63,7 +65,7 @@ Deleting an automatic Profile is ordinary deletion. A later discovery may create
 
 ## Persistence and retired Team data
 
-The generic registry writes `<HUABU_DATA_DIR>/agent-profiles/registry.json` atomically. On first initialization only, it imports ordinary command Profiles from the former `agent-team/registry.json` and, when applicable, the older `agent-profiles.json` source. IDs, directories, metadata and custom data are preserved. Initialization is persisted even for an empty list; an existing new registry is authoritative, so a deleted Profile cannot reappear through repeated migration. Invalid command data and conflicting identities fail explicitly.
+The generic registry writes `<HUABU_DATA_DIR>/agent-profiles/registry.json` atomically. On first initialization only, it imports ordinary command Profiles from the former `agent-team/registry.json`, whose records already carry device placement. IDs, directories, metadata and custom data are preserved. Huabu does not import the older `agent-profiles.json` format because those records have no device identity and assigning them to an arbitrary connected or supervised Agentlet would break placement continuity. Initialization is persisted even for an empty list; an existing new registry is authoritative, so a deleted Profile cannot reappear through repeated migration. Invalid command data and conflicting identities fail explicitly.
 
 Old Team registry/config/setup-log files and conversation records are not deleted or rewritten by migration. Manifest Profiles are not imported as active Profiles or converted to executable commands. Agentlet and Agenetes reject retired Team launch recipes instead of silently treating them as ordinary commands.
 
@@ -91,13 +93,15 @@ The Web client records the most recently explicitly selected conversational Prof
 
 Ink submission without an existing Question target refreshes the Profile catalogue and applies the same browser-local recent selection before creating its Question, using internal `operate` or external `ask` mode. It rejects a changed Space or selection after that await. Failed loading leaves the Ink selection intact and creates no node; an already selected Agent target and a retry of the same created Question keep their binding.
 
-`GET /api/acp/profiles` reads the canonical persisted list, selectable IDs, and saved `agentDefaults` without detecting harnesses, creating Profiles or starting sessions. Settings refreshes the shared Profile store on mount and after mutations; existing selectors refresh that same list when opened. There is no Web discovery store, selector-time materialization, or discovery polling.
+`GET /api/acp/profiles` reads the canonical persisted list, active connected devices, connectivity-filtered selectable IDs, supervised-child health, and saved `agentDefaults` without detecting harnesses, creating Profiles or starting sessions. The active device projection is sorted deterministically and contains the Agentlet UUID, display metadata, Agentlet version, connection time, and associated Profile count; it is not persisted and contains no offline history or last-seen state. A Profile is selectable only while its exact `agentletId` has an active control connection. Settings refreshes the shared Profile store on mount and after mutations; existing selectors refresh that same list when opened. Unavailable Profiles remain visible and editable in Settings but cannot be selected for runtime work. There is no Web discovery store, selector-time materialization, or discovery polling.
+
+`GET /api/acp/agent-cli` requires exactly one explicit target: `agentletId` for creation or `profileId` for editing. It includes launch support and capability observations without preparing workspaces or creating Profiles. Older successful catalogues receive the canonical Custom descriptor; failed detection remains an explicit error, not a misleading successful catalogue. Custom command configuration and display-only edits remain available without successful detection. Manual creation requires an active device and an explicit `workingDirPath`; only automatic defaults get a daemon-prepared directory.
 
-`GET /api/acp/agent-cli` adapts the supervised agentlet's read-only discovery response; optional `profileId` instead targets the saved Profile's machine. It includes launch support and capability observations without preparing workspaces or creating Profiles. Older successful catalogues receive the canonical Custom descriptor; failed detection remains an explicit error, not a misleading successful catalogue. Custom command configuration and display-only edits remain available without successful detection. Manual creation requires an explicit `workingDirPath`; only automatic defaults get a daemon-prepared directory.
+Owner-only `POST /api/acp/profile-launch-preview` requires `{ launch, agentletId }` for creation or `{ launch, profileId }` for editing and returns the explicitly targeted Agentlet's validated `exec`/`shell` plan. It never spawns an Agent or prepares a workspace. Unsupported or disconnected target previews fail explicitly. `POST /api/acp/profiles` requires an active `agentletId` and persists that immutable placement; Settings initializes the form with the first deterministically sorted active device only as an unsaved UI convenience. Profile creation and runtime-relevant patches independently validate structured launch support and options, so client-side controls are not the validation boundary. `PATCH /api/acp/profiles/:id` requires `expectedRevision` and permits mutable template fields only; display-only edits do not require a connected Agentlet.
 
-Owner-only `POST /api/acp/profile-launch-preview` accepts `{ launch, profileId? }`, selects the saved Profile's machine when editing, and returns the daemon's validated `exec`/`shell` plan. It never spawns an Agent or prepares a workspace. Unsupported/offline daemon previews fail explicitly. Profile creation and runtime-relevant patches independently validate structured launch support and options, so client-side controls are not the validation boundary. `PATCH /api/acp/profiles/:id` requires `expectedRevision` and permits mutable template fields only; display-only edits do not require a connected daemon.
+The Agent Settings surface presents active Connected Devices first, followed by ordinary Profiles, their existing edit/delete actions, and the supervised-child health banner alongside Utility Agent and backend-specific configuration. The create editor requires a device selection before harness selection; editing displays the immutable device identity read-only. Opening a Profile editor temporarily focuses that nested view without duplicating or rewriting Profile state. Template/member Config/setup controls are removed. Catalogue, Profile, Utility Agent, and conversational preference endpoints remain owner-only. Shared HTTP contracts remain under `packages/shared/src/types/api/`, with type-only imports in the Web app.
 
-The Agent Settings surface presents ordinary Profiles, their existing edit/delete actions, and the agentlet health banner alongside Utility Agent and backend-specific configuration. Opening a Profile editor temporarily focuses that nested view without duplicating or rewriting Profile state. Template/member Config/setup controls are removed. Catalogue, Profile, Utility Agent, and conversational preference endpoints remain owner-only. Shared HTTP contracts remain under `packages/shared/src/types/api/`, with type-only imports in the Web app.
+Workload placement is always explicit. New workloads snapshot the Profile's `agentletId`; existing snapshots continue to use their stored placement. A missing Profile or a legacy workload without placement is treated as invalid data and fails clearly. Runtime code never falls back to the supervised child, hostname, or first connected device.
 
 Owner-only `GET/PUT /api/acp/runtime-config` persists the external-agent idle timeout and supervised-daemon process limit in `<HUABU_DATA_DIR>/external-agent-runtime-config.json`; both controls appear under Settings > Agent > External Agent runtime. `maxAgents` defaults to `10` and accepts any positive JavaScript safe integer without a product-defined maximum. Huabu passes it as `--max-agents` whenever the supervised daemon starts; saving does not hot-update or automatically restart the daemon, and manually launched remote daemons continue to use their own CLI argument without a configuration handshake.
 
@@ -108,6 +112,7 @@ The same runtime section owns the masked Agentlet connection-token setting and o
 | File or directory                                                                                                       | Responsibility                                                     |
 | ----------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------ |
 | [`local/src/harnesses/`](../../external/agentlet/packages/local/src/harnesses/)                                         | Canonical catalogue, local detector and default workspaces         |
+| [`local/src/device-identity.ts`](../../external/agentlet/packages/local/src/device-identity.ts)                         | Persistent UUID device identity                                    |
 | [`protocol/src/messages.ts`](../../external/agentlet/packages/protocol/src/messages.ts)                                 | Harness discovery wire contract                                    |
 | [`agentlet-gateway/src/gateway.ts`](../../external/agenetes/packages/agentlet-gateway/src/gateway.ts)                   | Machine events and validated discovery routing                     |
 | [`packages/agent-profile/`](../../external/agenetes/packages/agent-profile/)                                            | Generic Profile registry, persistence and snapshots                |
diff --git a/docs/architecture/api-design.md b/docs/architecture/api-design.md
index 9766bc16d..515f2fd38 100644
--- a/docs/architecture/api-design.md
+++ b/docs/architecture/api-design.md
@@ -144,6 +144,8 @@ Malformed request fields and malformed cursors return HTTP 400 with `code: "malf
 
 `GET/PUT /api/acp/runtime-config` uses `externalAgentRuntimeConfigSchema` from [`acp.ts`](../../packages/shared/src/types/api/acp.ts). The owner-only full replacement body contains `idleTimeoutSecs` and `maxAgents`; `maxAgents` is a positive JavaScript safe integer with default `10` and no product-defined upper bound. The value is persisted globally and supplied to the supervised Agentlet daemon as `--max-agents` on its next start; the API does not restart the daemon or configure manually launched remote daemons.
 
+`GET /api/acp/profiles` returns persisted Profiles, active connected devices, connectivity-filtered `selectableProfileIds`, supervised-child health, and optional Agent defaults. `POST /api/acp/profiles` requires an explicit active `agentletId`. `GET /api/acp/agent-cli` and `POST /api/acp/profile-launch-preview` require exactly one explicit target: `agentletId` while creating or `profileId` while editing. The server validates every target against the live Gateway and never substitutes the supervised child or first connected device.
+
 ## Utility Agent selection
 
 `GET/PUT /api/agent/defaults` uses `agentDefaultsSchema` for the Utility Agent only: its Profile and optional functional-model override serve Huabu-owned auxiliary work and never choose a conversational binding. The recent conversational Agent is browser-local UI state and has no HTTP contract.
diff --git a/docs/proposals/agenetes-agentlet-gateway-consolidation.md b/docs/proposals/agenetes-agentlet-gateway-consolidation.md
index a40fe8a04..4145da2ad 100644
--- a/docs/proposals/agenetes-agentlet-gateway-consolidation.md
+++ b/docs/proposals/agenetes-agentlet-gateway-consolidation.md
@@ -2,7 +2,7 @@
 
 > Absorb the host-side agentlet relay into Agenetes, retire the standalone agentlet-server control plane, and make Agenetes the sole owner of durable workload and conversation state.
 >
-> Status: **Shipped** · Last updated: 2026-07-14
+> Status: **Shipped** · Last updated: 2026-10-02
 
 ---
 
@@ -85,25 +85,25 @@ Every daemon-directed operation carries an explicit stable `agentletId`. The gat
 
 Connection registries and ACP session caches are scoped by agentlet identity. A control connection disconnect or replacement affects only control operations for that daemon; existing session connections remain usable and are invalidated only when their own sockets disconnect. No event for one daemon invalidates another daemon's connections or caches.
 
-In the first version, `agentletId` is the daemon's machine name. For Huabu's supervised local daemon, the host reads `os.hostname()` at startup and passes the same value to the Gateway and the daemon's `--agentlet-id` option. No additional local identity file is introduced.
+Agentlet owns its default `agentletId` as a persistent UUID in `~/.agentlet/device.json`. The supervised host does not inject an identity; it controls only child-process lifecycle. `--agentlet-id` remains an exact advanced override that does not rewrite the persisted UUID.
 
-For backward compatibility, persisted ACP WorkloadSpecs created before placement was introduced may omit `agentletId`. The ACP composition resolves only those legacy specs to the host-injected supervised local daemon ID. This is a read-time compatibility rule: it does not rewrite the durable WorkloadSpec and never selects from the set of currently connected daemons.
+Persisted ACP WorkloadSpecs without `agentletId` fail explicitly. The composition never substitutes the supervised child, hostname, or first connected Agentlet.
 
-Every newly compiled ACP WorkloadSpec includes an explicit `agentletId`. A missing ID is therefore accepted only when reading a legacy record, not when creating a new workload.
+Every newly compiled ACP WorkloadSpec includes the immutable `agentletId` from its selected Profile.
 
-Changing the machine name, including changing the supervised host's OS hostname, creates a new execution node identity. Existing roots, deployments, and explicit workload bindings remain attached to the old identity and become unavailable rather than migrating implicitly.
+Changing the machine hostname does not change device identity. Replacing or deleting the home directory creates a new device identity; existing roots, deployments, Profiles, and explicit workload bindings remain attached to the old UUID and become unavailable rather than migrating implicitly.
 
-Huabu's supervised local daemon uses the existing process-lifetime connection token generated by the host and injected into its child process. The host and daemon restart together, so this token does not require persistence.
+Huabu's supervised local daemon and manually launched remote daemons use the same active host connection token. Token persistence and rotation are host concerns and remain independent from device identity.
 
-Future remote daemons each use their own long-lived token. The operator manually configures the same `{ machineName, token }` pair on the remote daemon and the Agenetes host.
+The operator supplies the active token to each remote daemon; every daemon independently reports its persistent UUID.
 
-The gateway authenticates both the daemon control WebSocket and every session WebSocket independently through a host-injected `authenticateAgentlet(machineName, token)` port. A credential may claim only its configured machine name, and the claimed name must match `sessionProfile.agentletId` on a session hello. A session connection does not require its daemon's control socket to be online.
+The gateway authenticates both the daemon control WebSocket and every session WebSocket independently through a host-injected `authenticateAgentlet(agentletId, token)` port. Huabu's shared connection token authorizes any Agentlet identity; the claimed control identity must match `sessionProfile.agentletId` on a session hello. A session connection does not require its daemon's control socket to be online.
 
 The gateway does not persist credentials. The supervised local token remains host-process state; Huabu stores future remote daemon tokens through its SecretStore-backed host adapter.
 
 Remote token changes and revocation are startup-time operations in the first version that supports remote configuration. After changing configuration on both sides, the operator restarts the Gateway host and the corresponding daemon. There is no runtime rotation notification or connection-eviction API in this migration.
 
-Registering a live duplicate machine name with the configured credential replaces the old control socket as a reconnect without closing that machine's session sockets. A duplicate machine name using a different credential is rejected.
+Registering a live duplicate Agentlet identity is rejected instead of evicting the existing control socket. Once the prior control connection disconnects, the same identity follows the normal reconnect path without closing that device's session sockets.
 
 ### 6.3 Connection topology and session identity
 
@@ -116,7 +116,7 @@ The gateway keys a session connection by `(agentletId, nativeAcpSessionId)`. Nat
 
 Agenetes `ThreadIdentity` remains a durable control-plane identity and is not part of the session WebSocket identity. Agenetes owns the binding from a thread to its placed daemon and native ACP session.
 
-Both connection types use the credential bound to the claimed daemon machine name, but their connection lifecycles remain independent.
+Both connection types use the shared host credential and the same claimed Agentlet identity, but their connection lifecycles remain independent.
 
 ### 6.4 Preserve current reconnect and buffer behavior
 
@@ -190,7 +190,7 @@ The migration is feasible with a contained blast radius:
 The primary implementation risks are:
 
 1. Losing bootstrap `session/update` notifications when EventStore is removed. The bounded inbound pre-attach buffer is a required migration mechanism.
-2. Accidentally falling back to the first connected daemon. New ACP specs and every spawn/cache path require explicit placement; only legacy persisted specs may use the host-injected supervised local daemon ID.
+2. Accidentally falling back to an implicit daemon. ACP specs and every spawn/cache path require explicit placement; legacy persisted specs without placement fail clearly.
 3. Cascading a control disconnect or reconnect into otherwise healthy session connections. Control and session registries must be keyed by daemon but lifecycled independently.
 4. Breaking the repository between package moves. The Gateway must be added and adopted before the agentlet server package is deleted.
 
@@ -246,14 +246,14 @@ Changes under `external/agentlet/` are always committed separately from Agenetes
 
 ### G2 — Make daemon machine identity explicit
 
-| Item       | Detail                                                                                                                                                                                                                                                                                                                                  |
-| ---------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
-| Status     | ✅ Complete.                                                                                                                                                                                                                                                                                                                            |
-| Scope      | `external/agentlet/packages/local/` and the corresponding Agentlet protocol documentation.                                                                                                                                                                                                                                              |
-| Work       | Use the daemon's machine name as `agentletId` on control and session hello, accept an explicit `--agentlet-id` from the supervising host, keep the existing token and daemon reconnect behavior, and remove direct bridge mode. G3 derives Huabu's supervised local ID from `os.hostname()` and injects the same value into both sides. |
-| Dependency | G0; may proceed in parallel with G1.                                                                                                                                                                                                                                                                                                    |
-| Validation | Control and session connections report the same machine name; changing the supervised host's hostname produces a new execution-node identity; existing daemon tests pass.                                                                                                                                                               |
-| Commit     | Agentlet-subtree-only commit.                                                                                                                                                                                                                                                                                                           |
+| Item       | Detail                                                                                                                                                                                                                     |
+| ---------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| Status     | ✅ Complete.                                                                                                                                                                                                               |
+| Scope      | `external/agentlet/packages/local/` and the corresponding Agentlet protocol documentation.                                                                                                                                 |
+| Work       | Use one Agentlet-owned persistent UUID as `agentletId` on control and session hello, retain an exact `--agentlet-id` override, keep token and reconnect behavior independent from identity, and remove direct bridge mode. |
+| Dependency | G0; may proceed in parallel with G1.                                                                                                                                                                                       |
+| Validation | Control and session connections report the same UUID; restart reuses the identity; malformed identity files fail explicitly; hostname remains display metadata; existing daemon tests pass.                                |
+| Commit     | Agentlet-subtree-only commit.                                                                                                                                                                                              |
 
 ### G3 — Mount Gateway through the existing host package
 
@@ -268,14 +268,14 @@ Changes under `external/agentlet/` are always committed separately from Agenetes
 
 ### G4 — Persist explicit ACP placement in the driver spec
 
-| Item       | Detail                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
-| ---------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
-| Status     | ✅ Complete.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
-| Scope      | `external/agenetes/packages/acp-driver/` plus Agenetes protocol binding definitions.                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
-| Work       | Add explicit `agentletId` placement to the ACP driver-specific create spec/binding recipe. Keep the persisted read shape backward-compatible with legacy records that omit it, resolving only those records to the host-injected supervised local daemon ID without durable migration or write-back. Because Agenetes already persists the complete WorkloadSpec in ThreadRecord, no separate generic thread-store placement field is added. Re-key live ACP caches by `(agentletId, threadId)` and remove every `getAgentlets()[0]` selection. |
-| Dependency | G1 and G3.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
-| Validation | New persisted ACP WorkloadSpecs retain explicit placement across restart; a legacy spec without placement resolves to the configured supervised local daemon without being rewritten; reconnecting daemon B does not invalidate daemon A sessions; missing target daemon produces a structured placement error.                                                                                                                                                                                                                                 |
-| Commit     | Agenetes-only commit.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
+| Item       | Detail                                                                                                                                                                                                                                                                                                                                                                                                                                               |
+| ---------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| Status     | ✅ Complete.                                                                                                                                                                                                                                                                                                                                                                                                                                         |
+| Scope      | `external/agenetes/packages/acp-driver/` plus Agenetes protocol binding definitions.                                                                                                                                                                                                                                                                                                                                                                 |
+| Work       | Add explicit `agentletId` placement to the ACP driver-specific create spec/binding recipe. Keep the persisted read shape capable of parsing legacy records but fail realization when placement is absent. Because Agenetes already persists the complete WorkloadSpec in ThreadRecord, no separate generic thread-store placement field is added. Re-key live ACP caches by `(agentletId, threadId)` and remove every `getAgentlets()[0]` selection. |
+| Dependency | G1 and G3.                                                                                                                                                                                                                                                                                                                                                                                                                                           |
+| Validation | New persisted ACP WorkloadSpecs retain explicit placement across restart; a legacy spec without placement resolves to the configured supervised local daemon without being rewritten; reconnecting daemon B does not invalidate daemon A sessions; missing target daemon produces a structured placement error.                                                                                                                                      |
+| Commit     | Agenetes-only commit.                                                                                                                                                                                                                                                                                                                                                                                                                                |
 
 ### G5 — Remove ACP driver reads from agentlet stores
 
@@ -290,14 +290,14 @@ Changes under `external/agentlet/` are always committed separately from Agenetes
 
 ### G6 — Switch Huabu to the Gateway
 
-| Item       | Detail                                                                                                                                                                                                                                                                                                                                                                      |
-| ---------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
-| Status     | ✅ Complete.                                                                                                                                                                                                                                                                                                                                                                |
-| Scope      | Server mount wiring, package dependencies, build scripts, daemon status projection, and current External Agent composition.                                                                                                                                                                                                                                                 |
-| Work       | Register the supervised local daemon's machine name/token through the host authentication adapter, supply its `agentletId` when compiling ACP WorkloadSpecs, mount the Gateway, retain the existing single-agentlet status projection and restart endpoints, and remove runtime calls to `@agentlet/server`. Remote daemon configuration UI remains outside this migration. |
-| Dependency | G3–G5.                                                                                                                                                                                                                                                                                                                                                                      |
-| Validation | Existing External Agent flows work against the supervised local daemon; server restarts recover through Agenetes; no application code imports `@agentlet/server`.                                                                                                                                                                                                           |
-| Commit     | Huabu-only commit; must not touch `external/agentlet/`.                                                                                                                                                                                                                                                                                                                     |
+| Item       | Detail                                                                                                                                                                                                                                                                                                                    |
+| ---------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| Status     | ✅ Complete.                                                                                                                                                                                                                                                                                                              |
+| Scope      | Server mount wiring, package dependencies, build scripts, daemon status projection, and current External Agent composition.                                                                                                                                                                                               |
+| Work       | Register the shared connection token through the host authentication adapter, compile ACP WorkloadSpecs from explicit Profile placement, mount the Gateway, retain supervisor lifecycle status and restart endpoints without treating the child as an identity authority, and remove runtime calls to `@agentlet/server`. |
+| Dependency | G3–G5.                                                                                                                                                                                                                                                                                                                    |
+| Validation | Existing External Agent flows work against the supervised local daemon; server restarts recover through Agenetes; no application code imports `@agentlet/server`.                                                                                                                                                         |
+| Commit     | Huabu-only commit; must not touch `external/agentlet/`.                                                                                                                                                                                                                                                                   |
 
 ### G7 — Remove standalone agentlet-server
 
diff --git a/external/agenetes/packages/acp-driver/src/driver.test.ts b/external/agenetes/packages/acp-driver/src/driver.test.ts
index 337761c08..a31a7d1f0 100644
--- a/external/agenetes/packages/acp-driver/src/driver.test.ts
+++ b/external/agenetes/packages/acp-driver/src/driver.test.ts
@@ -5,7 +5,6 @@
 // keyed by `workload.threadId` (I9.3). The driver payload is nested under
 // `workload.spec` and validated by the mounted driver.
 
-import { getSupervisedAgentletId } from '@agenetes/agentlet-host';
 import { describe, expect, it } from 'vitest';
 
 import { acpDriverFactory } from './driver.js';
@@ -104,7 +103,7 @@ describe('acpDriverFactory (M5 FACTORY)', () => {
     ).rejects.toThrow();
   });
 
-  it('preserves explicit placement and resolves legacy specs without mutation', () => {
+  it('preserves explicit placement and rejects legacy specs without placement', () => {
     const explicit: AcpCreateSpec = {
       kind: 'acp',
       workloadType: 'Deployment',
@@ -124,7 +123,9 @@ describe('acpDriverFactory (M5 FACTORY)', () => {
     };
 
     expect(resolveAcpAgentletId(explicit)).toBe('machine-b');
-    expect(resolveAcpAgentletId(legacy)).toBe(getSupervisedAgentletId());
+    expect(() => resolveAcpAgentletId(legacy)).toThrow(
+      'The workload has no Agentlet placement.',
+    );
     expect('agentletId' in legacy.spec).toBe(false);
   });
 
@@ -136,7 +137,10 @@ describe('acpDriverFactory (M5 FACTORY)', () => {
         workloadType: 'Deployment',
         threadId: 'thr_1',
         namespace: { name: 'canvas_1', storage: { root: '/data/c1' } },
-        spec: { binding: { alias: 'copilot', profileId: 'prof_1' } },
+        spec: {
+          agentletId: 'machine-a',
+          binding: { alias: 'copilot', profileId: 'prof_1' },
+        },
       },
       freshContext,
     );
@@ -188,6 +192,7 @@ describe('acpDriverFactory (M5 FACTORY)', () => {
         threadId: 'thr_2',
         namespace: { name: 'canvas_1', storage: { root: '/data/c1' } },
         spec: {
+          agentletId: 'machine-a',
           binding: { alias: 'claude', profileId: 'prof_2' },
           cwd: '/work',
           recipe: null,
diff --git a/external/agenetes/packages/acp-driver/src/handle.ts b/external/agenetes/packages/acp-driver/src/handle.ts
index 07b21a611..986fd35fd 100644
--- a/external/agenetes/packages/acp-driver/src/handle.ts
+++ b/external/agenetes/packages/acp-driver/src/handle.ts
@@ -33,7 +33,6 @@
 
 import { randomUUID } from 'node:crypto';
 
-import { getSupervisedAgentletId } from '@agenetes/agentlet-host';
 import { resolveAgentInputs } from '@agenetes/protocol';
 import {
   HistoryLoadDeniedError,
@@ -236,9 +235,15 @@ export async function resolveAcpRuntimeLaunch(
   };
 }
 
-/** Resolve explicit placement or the read-only legacy local fallback. */
+/** Resolve the immutable execution-node placement stored in the workload. */
 export function resolveAcpAgentletId(spec: AcpCreateSpec): string {
-  return spec.spec.agentletId ?? getSupervisedAgentletId();
+  if (!spec.spec.agentletId) {
+    throw new AcpServiceError(
+      'placement_unavailable',
+      'The workload has no Agentlet placement.',
+    );
+  }
+  return spec.spec.agentletId;
 }
 
 /** The per-turn context an {@link AcpAgentHandle.run} accepts. */
diff --git a/external/agenetes/packages/acp-driver/src/placement.test.ts b/external/agenetes/packages/acp-driver/src/placement.test.ts
index 00e5d6cc1..9b08f2aca 100644
--- a/external/agenetes/packages/acp-driver/src/placement.test.ts
+++ b/external/agenetes/packages/acp-driver/src/placement.test.ts
@@ -10,11 +10,6 @@ vi.mock('@agenetes/agentlet-host', async (importOriginal) => {
   return {
     ...actual,
     getAgentletGateway: () => host.gateway,
-    getSupervisedAgentletId: () => 'machine-a',
-    getDaemonSupervisor: () => ({
-      getStatus: () => ({ online: false }),
-      hasGivenUp: () => false,
-    }),
   };
 });
 
diff --git a/external/agenetes/packages/acp-driver/src/spawn-orchestrator.ts b/external/agenetes/packages/acp-driver/src/spawn-orchestrator.ts
index a3b7a3dee..6571149ba 100644
--- a/external/agenetes/packages/acp-driver/src/spawn-orchestrator.ts
+++ b/external/agenetes/packages/acp-driver/src/spawn-orchestrator.ts
@@ -39,9 +39,7 @@
 
 import {
   AgentletRequestError,
-  getDaemonSupervisor,
   getAgentletGateway,
-  getSupervisedAgentletId,
 } from '@agenetes/agentlet-host';
 import {
   harnessLaunchPlanSchema,
@@ -71,10 +69,8 @@ export function isSessionResumeUnavailableError(error: unknown): boolean {
  * Gatekeeper systems. Subsequent launches are usually subsecond
  * because the OS has the files cached.
  *
- * We still short-circuit the wait as soon as the supervisor reports
- * `hasGivenUp()` (agentlet entry missing, repeated crashes, …) so a
- * truly broken install does not make every UI affordance hang for
- * the full window.
+ * Placement is independent from process supervision, so every target
+ * receives the same connection grace period.
  */
 const AGENTLET_READY_TIMEOUT_MS = 20_000;
 
@@ -109,20 +105,15 @@ function readTargetAgentlet(agentletId: string): { agentletId: string } | null {
 /**
  * Poll {@link readTargetAgentlet} until the target agentlet is online or
  * `timeoutMs` elapses. Returns the resolved descriptor or `null` on
- * timeout (or as soon as the supervisor has stopped trying).
+ * timeout.
  */
 async function waitForTargetAgentlet(
   agentletId: string,
   timeoutMs: number,
 ): Promise<{ agentletId: string } | null> {
   const deadline = Date.now() + timeoutMs;
-  const supervisor = getDaemonSupervisor();
-  const supervisedAgentletId = getSupervisedAgentletId();
   let agentlet = readTargetAgentlet(agentletId);
   while (!agentlet && Date.now() < deadline) {
-    if (agentletId === supervisedAgentletId && supervisor.hasGivenUp()) {
-      return null;
-    }
     await new Promise((r) => setTimeout(r, 100));
     agentlet = readTargetAgentlet(agentletId);
   }
@@ -178,10 +169,10 @@ async function waitForAgentConnection(
  * Cold-start tolerance: we wait up to {@link AGENTLET_READY_TIMEOUT_MS}
  * for the agentlet to come online and up to 3 s for the freshly-spawned
  * agent to finish its handshake. Only after both windows expire (or the
- * supervisor reports it has given up) do we surface a user-facing error.
+ * target stays unavailable) do we surface a user-facing error.
  *
  * Throws when:
- *   • the supervisor never brings the agentlet online (truly offline),
+ *   • the target agentlet does not come online,
  *   • the agentlet RPC for spawn fails.
  *
  * Idempotent within a single agentlet's lifetime — repeat calls for
@@ -208,16 +199,9 @@ export async function ensureAgentForThread(
     AGENTLET_READY_TIMEOUT_MS,
   );
   if (!agentlet) {
-    const supervisorStatus =
-      agentletId === getSupervisedAgentletId()
-        ? getDaemonSupervisor().getStatus()
-        : null;
-    const hint = supervisorStatus?.lastError
-      ? ` (${supervisorStatus.lastError})`
-      : '';
     throw new AcpServiceError(
       'placement_unavailable',
-      `Target agentlet '${agentletId}' is not connected${hint}.`,
+      `Target agentlet '${agentletId}' is not connected.`,
     );
   }
 
diff --git a/external/agenetes/packages/agentlet-host/src/daemon-auth.ts b/external/agenetes/packages/agentlet-host/src/daemon-auth.ts
index a6dd2619a..5d91122f6 100644
--- a/external/agenetes/packages/agentlet-host/src/daemon-auth.ts
+++ b/external/agenetes/packages/agentlet-host/src/daemon-auth.ts
@@ -55,11 +55,6 @@ class AcpDaemonAuth {
     this.token = token;
   }
 
-  /** Configure the identity and token accepted for the supervised daemon. */
-  configure(_agentletId: string, token: string): void {
-    this.token = token;
-  }
-
   /**
    * Mint and store a fresh 256-bit hex token. Retained for tests /
    * fallback; the production path injects a stable token via
diff --git a/external/agenetes/packages/agentlet-host/src/daemon-supervisor.ts b/external/agenetes/packages/agentlet-host/src/daemon-supervisor.ts
index 324b4c1d7..6dc6e200e 100644
--- a/external/agenetes/packages/agentlet-host/src/daemon-supervisor.ts
+++ b/external/agenetes/packages/agentlet-host/src/daemon-supervisor.ts
@@ -31,10 +31,10 @@
  *
  * ### Status reporting
  *
- * `getDaemonStatus()` combines the supervisor's view (last error,
- * backoff schedule) with the Gateway's view (is a daemon
- * actually registered right now?). The UI uses the merged snapshot
- * to decide whether to show the amber troubleshooting block.
+ * `getDaemonStatus()` reports only the supervised child lifecycle.
+ * Connected Agentlet devices are projected separately by the host,
+ * because the child owns its device identity and the supervisor must
+ * not infer it from an arbitrary Gateway connection.
  *
  * ### Entry resolution
  *
@@ -48,11 +48,9 @@
 
 import { fork } from 'node:child_process';
 import { existsSync, unlinkSync } from 'node:fs';
-import { hostname } from 'node:os';
 import { join } from 'node:path';
 
 import { getDaemonAuth } from './daemon-auth.js';
-import { getAgentletGateway } from './gateway-mount.js';
 
 import type { AgentletStatus } from '@agenetes/protocol';
 import type { FastifyInstance } from 'fastify';
@@ -230,8 +228,6 @@ export interface AttachOptions {
   daemonEntryPath: string;
   /** Absolute directory for host-owned persistent state. */
   dataDir: string;
-  /** Machine identity shared by the daemon and Gateway authenticator. */
-  agentletId?: string;
   /** Resolve the host-owned process limit each time the daemon starts. */
   getMaxAgents?: () => number;
   /**
@@ -300,7 +296,6 @@ class DaemonSupervisor {
    * {@link attach} time. Used only for legacy-ticket cleanup here.
    */
   private dataDir = '';
-  private agentletId = '';
   private getMaxAgents: (() => number) | undefined;
   private hostEnvPrefix: string | undefined;
   private hostEnvAllowlist: readonly string[] | undefined;
@@ -314,7 +309,6 @@ class DaemonSupervisor {
     this.app = app;
     this.daemonEntryPath = opts.daemonEntryPath;
     this.dataDir = opts.dataDir;
-    this.agentletId = opts.agentletId ?? hostname();
     this.getMaxAgents = opts.getMaxAgents;
     this.hostEnvPrefix = opts.hostEnvPrefix;
     this.hostEnvAllowlist = opts.hostEnvAllowlist;
@@ -409,24 +403,9 @@ class DaemonSupervisor {
     getDaemonAuth().close();
   }
 
-  /**
-   * Merge the supervisor's view with the Gateway's daemon
-   * registry to produce the wire snapshot consumed by the UI.
-   */
+  /** Project the supervised child lifecycle for the UI health surface. */
   getStatus(): AgentletStatus {
-    const gateway = getAgentletGateway();
-    const live = gateway?.getAgentlets({ status: 'connected' }) ?? [];
-    const agentlet = live[0];
-
-    if (agentlet) {
-      return {
-        online: true,
-        agentletId: agentlet.agentletId,
-        hostname: agentlet.agentletProfile?.machine?.hostname,
-        platform: agentlet.agentletProfile?.machine?.platform,
-        connectedAt: agentlet.connectedAt.toISOString(),
-      };
-    }
+    if (this.state.child && !this.state.child.killed) return { online: true };
 
     const status: AgentletStatus = { online: false };
     if (this.state.lastError) status.lastError = this.state.lastError;
@@ -467,8 +446,6 @@ class DaemonSupervisor {
       serverUrl,
       '--token',
       token,
-      '--agentlet-id',
-      this.agentletId,
       ...(maxAgents === undefined ? [] : ['--max-agents', String(maxAgents)]),
       '--allow-insecure',
     ];
diff --git a/external/agenetes/packages/agentlet-host/src/gateway-mount.test.ts b/external/agenetes/packages/agentlet-host/src/gateway-mount.test.ts
index 47b577363..083e15cc4 100644
--- a/external/agenetes/packages/agentlet-host/src/gateway-mount.test.ts
+++ b/external/agenetes/packages/agentlet-host/src/gateway-mount.test.ts
@@ -23,7 +23,7 @@ afterEach(async () => {
 describe('Agentlet Gateway mount', () => {
   it('accepts the shared token from another machine identity', () => {
     const auth = getDaemonAuth();
-    auth.configure('machine-a', 'test-token');
+    auth.setDaemonToken('test-token');
 
     expect(() =>
       auth.validateAgentlet('machine-b', 'test-token'),
@@ -31,7 +31,7 @@ describe('Agentlet Gateway mount', () => {
   });
 
   it('authenticates the supervised identity and closes upgraded sockets', async () => {
-    getDaemonAuth().configure('machine-a', 'test-token');
+    getDaemonAuth().setDaemonToken('test-token');
     app = Fastify({ logger: false });
     const gateway = mountAgentletGateway(app, {});
     await app.listen({ host: '127.0.0.1', port: 0 });
diff --git a/external/agenetes/packages/agentlet-host/src/index.ts b/external/agenetes/packages/agentlet-host/src/index.ts
index 52188ba93..f0a3c4d88 100644
--- a/external/agenetes/packages/agentlet-host/src/index.ts
+++ b/external/agenetes/packages/agentlet-host/src/index.ts
@@ -15,8 +15,6 @@
  *
  */
 
-import { hostname } from 'node:os';
-
 import { mountAgentProfileRegistry } from './agent-profile-mount.js';
 import { getDaemonAuth } from './daemon-auth.js';
 import { getDaemonSupervisor } from './daemon-supervisor.js';
@@ -30,13 +28,6 @@ import type {
 } from '@agenetes/agentlet-gateway';
 import type { FastifyInstance } from 'fastify';
 
-const supervisedAgentletId = hostname();
-
-/** Machine identity used by Sediment's supervised local daemon. */
-export function getSupervisedAgentletId(): string {
-  return supervisedAgentletId;
-}
-
 export { getAgentProfileRegistry } from './agent-profile-mount.js';
 export {
   ACP_UPGRADE_PATH,
@@ -135,8 +126,7 @@ export function mountAgenetes(
   app: FastifyInstance,
   opts: MountAgenetesOptions,
 ): AgentletGateway {
-  const agentletId = getSupervisedAgentletId();
-  getDaemonAuth().configure(agentletId, opts.connectionToken);
+  getDaemonAuth().setDaemonToken(opts.connectionToken);
 
   const gateway = mountAgentletGateway(app, {
     authenticate: opts.authenticate,
@@ -149,7 +139,6 @@ export function mountAgenetes(
   getDaemonSupervisor().attach(app, {
     daemonEntryPath: opts.daemonEntryPath,
     dataDir: opts.dataDir,
-    agentletId,
     getMaxAgents: opts.getMaxAgents,
     hostEnvPrefix: opts.hostEnvPrefix,
     hostEnvAllowlist: opts.hostEnvAllowlist,
diff --git a/external/agentlet/README.md b/external/agentlet/README.md
index 6a77e8420..8d28f8fb5 100644
--- a/external/agentlet/README.md
+++ b/external/agentlet/README.md
@@ -61,7 +61,7 @@ Important options:
 
 | Option | Meaning |
 | --- | --- |
-| `--agentlet-id <id>` | Stable execution-node identity; defaults to the machine hostname. |
+| `--agentlet-id <id>` | Exact execution-node identity override; the default is the persistent UUID in `~/.agentlet/device.json`. |
 | `--max-agents <count>` | Maximum number of concurrently managed agent processes. |
 | `--buffer-limit <count>` | Buffer capacity advertised in daemon and session profiles. |
 | `--reconnect-max <seconds>` | Maximum exponential reconnect delay. |
diff --git a/external/agentlet/packages/local/src/agentlet.ts b/external/agentlet/packages/local/src/agentlet.ts
index 8b2ce5865..813db98a3 100644
--- a/external/agentlet/packages/local/src/agentlet.ts
+++ b/external/agentlet/packages/local/src/agentlet.ts
@@ -1,4 +1,4 @@
-import { hostname, platform } from 'node:os'
+import { arch, hostname, platform } from 'node:os'
 import { join, resolve } from 'node:path'
 import { existsSync, mkdirSync, writeFileSync } from 'node:fs'
 import WebSocket from 'ws'
@@ -31,6 +31,7 @@ import {
   type SessionProfile,
 } from './session-bootstrap.js'
 import type { AgentletOptions } from './cli.js'
+import { resolveDeviceIdentity } from './device-identity.js'
 
 interface ManagedAgent {
   sessionId: string
@@ -57,9 +58,9 @@ const EARLY_MESSAGE_BUFFER_CAP = 1000
 
 export function resolveAgentletId(
   configuredId: string | undefined,
-  machineHostname = hostname(),
+  identityPath?: string,
 ): string {
-  return configuredId?.trim() || machineHostname
+  return configuredId?.trim() || resolveDeviceIdentity(identityPath)
 }
 
 /**
@@ -74,6 +75,11 @@ export class Agentlet {
   private shutdownInProgress = false
 
   private readonly daemonId: string
+  private readonly machine = {
+    hostname: hostname(),
+    platform: platform(),
+    arch: arch(),
+  }
   private controlWs: WebSocket | null = null
   private readonly agents = new Map<string, ManagedAgent>()
   private pendingSpawns = 0
@@ -201,7 +207,7 @@ export class Agentlet {
   private sendDaemonHello(): void {
     const agentletProfile: AgentletProfile = {
       bridge: { name: 'agentlet', version: PROTOCOL_VERSION },
-      machine: { hostname: this.daemonId, platform: platform() },
+      machine: this.machine,
       capabilities: {
         autoRestart: true,
         bufferLimit: this.options.bufferLimit,
@@ -597,7 +603,7 @@ export class Agentlet {
         capabilities: { autoRestart, bufferLimit: this.options.bufferLimit },
         heartbeatInterval: this.options.heartbeat,
         allowInsecure: this.options.allowInsecure,
-        machine: { hostname: this.daemonId, platform: platform() },
+        machine: this.machine,
       })
 
       managed.ws = agentWs
diff --git a/external/agentlet/packages/local/src/cli.ts b/external/agentlet/packages/local/src/cli.ts
index 7965d0bac..eebfcf2d6 100644
--- a/external/agentlet/packages/local/src/cli.ts
+++ b/external/agentlet/packages/local/src/cli.ts
@@ -43,7 +43,10 @@ export function parseCli(argv: string[]): CliResult {
     .option('--reconnect-max <seconds>', 'Maximum reconnection backoff in seconds', '300')
     .option('--buffer-limit <count>', 'Max messages buffered during disconnection', '1000')
     .option('--max-agents <count>', 'Maximum concurrent agents', '10')
-    .option('--agentlet-id <id>', 'Machine identity reported to the host (defaults to hostname)')
+    .option(
+      '--agentlet-id <id>',
+      'Device identity reported to the host (defaults to the persisted device UUID)',
+    )
     .option('--log-level <level>', 'Logging verbosity: debug, info, warn, error', 'info')
     .option('--log-file <path>', 'Path to write structured log output (JSON lines)')
     .option('--heartbeat <seconds>', 'WebSocket ping interval in seconds (0 to disable)', '30')
diff --git a/external/agentlet/packages/local/src/device-identity.ts b/external/agentlet/packages/local/src/device-identity.ts
new file mode 100644
index 000000000..2a37c097d
--- /dev/null
+++ b/external/agentlet/packages/local/src/device-identity.ts
@@ -0,0 +1,85 @@
+import {
+  closeSync,
+  existsSync,
+  fsyncSync,
+  linkSync,
+  mkdirSync,
+  openSync,
+  readFileSync,
+  unlinkSync,
+  writeFileSync,
+} from 'node:fs'
+import { homedir } from 'node:os'
+import { basename, dirname, join } from 'node:path'
+import { randomUUID } from 'node:crypto'
+
+interface DeviceIdentityFile {
+  version: 1
+  deviceId: string
+}
+
+const UUID_PATTERN =
+  /^[0-9a-f]{8}-[0-9a-f]{4}-[1-5][0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/i
+
+export function defaultDeviceIdentityPath(): string {
+  return join(homedir(), '.agentlet', 'device.json')
+}
+
+function parseDeviceIdentity(path: string): string {
+  let parsed: unknown
+  try {
+    parsed = JSON.parse(readFileSync(path, 'utf8'))
+  } catch (error) {
+    throw new Error(
+      `Agentlet device identity is unreadable at ${path}: ${
+        error instanceof Error ? error.message : String(error)
+      }`,
+    )
+  }
+  if (
+    !parsed ||
+    typeof parsed !== 'object' ||
+    (parsed as Partial<DeviceIdentityFile>).version !== 1 ||
+    typeof (parsed as Partial<DeviceIdentityFile>).deviceId !== 'string' ||
+    !UUID_PATTERN.test((parsed as DeviceIdentityFile).deviceId)
+  ) {
+    throw new Error(`Agentlet device identity is invalid at ${path}`)
+  }
+  return (parsed as DeviceIdentityFile).deviceId
+}
+
+export function resolveDeviceIdentity(
+  path = defaultDeviceIdentityPath(),
+): string {
+  mkdirSync(dirname(path), { recursive: true, mode: 0o700 })
+  if (existsSync(path)) return parseDeviceIdentity(path)
+
+  const deviceId = randomUUID()
+  const temporaryPath = join(
+    dirname(path),
+    `.${basename(path)}.${process.pid}.${randomUUID()}.tmp`,
+  )
+  let descriptor: number | undefined
+  try {
+    descriptor = openSync(temporaryPath, 'wx', 0o600)
+    writeFileSync(
+      descriptor,
+      `${JSON.stringify({ version: 1, deviceId } satisfies DeviceIdentityFile)}\n`,
+      'utf8',
+    )
+    fsyncSync(descriptor)
+    closeSync(descriptor)
+    descriptor = undefined
+    linkSync(temporaryPath, path)
+  } catch (error) {
+    if ((error as NodeJS.ErrnoException).code !== 'EEXIST') throw error
+  } finally {
+    if (descriptor !== undefined) closeSync(descriptor)
+    try {
+      unlinkSync(temporaryPath)
+    } catch (error) {
+      if ((error as NodeJS.ErrnoException).code !== 'ENOENT') throw error
+    }
+  }
+  return parseDeviceIdentity(path)
+}
diff --git a/external/agentlet/packages/local/src/ws-client.ts b/external/agentlet/packages/local/src/ws-client.ts
index 9a2dc2bfc..98c201453 100644
--- a/external/agentlet/packages/local/src/ws-client.ts
+++ b/external/agentlet/packages/local/src/ws-client.ts
@@ -33,7 +33,7 @@ export interface WsClientOptions {
   capabilities: { autoRestart: boolean; bufferLimit: number; maxAgents?: number }
   heartbeatInterval?: number
   allowInsecure?: boolean
-  machine?: { hostname: string; platform: string }
+  machine?: { hostname: string; platform: string; arch: string }
 }
 
 export interface WsClientEvents {
diff --git a/external/agentlet/packages/local/tests/agentlet.test.ts b/external/agentlet/packages/local/tests/agentlet.test.ts
index 77a354913..74a4d278a 100644
--- a/external/agentlet/packages/local/tests/agentlet.test.ts
+++ b/external/agentlet/packages/local/tests/agentlet.test.ts
@@ -1,4 +1,7 @@
-import { describe, expect, it } from 'vitest'
+import { mkdtempSync, readFileSync, rmSync, writeFileSync } from 'node:fs'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { afterEach, describe, expect, it } from 'vitest'
 
 import {
   buildAgentProcessEnv,
@@ -7,9 +10,33 @@ import {
 import { parseCli } from '../src/cli.js'
 
 describe('agentlet daemon identity', () => {
-  it('uses the current machine hostname when no identity is injected', () => {
-    expect(resolveAgentletId(undefined, 'machine-a')).toBe('machine-a')
-    expect(resolveAgentletId(undefined, 'machine-b')).toBe('machine-b')
+  const directories: string[] = []
+
+  afterEach(() => {
+    for (const directory of directories.splice(0)) {
+      rmSync(directory, { recursive: true, force: true })
+    }
+  })
+
+  function identityPath(): string {
+    const directory = mkdtempSync(join(tmpdir(), 'agentlet-device-'))
+    directories.push(directory)
+    return join(directory, 'device.json')
+  }
+
+  it('creates and reuses one persisted UUID by default', () => {
+    const path = identityPath()
+    const first = resolveAgentletId(undefined, path)
+    const second = resolveAgentletId(undefined, path)
+
+    expect(first).toMatch(
+      /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/,
+    )
+    expect(second).toBe(first)
+    expect(JSON.parse(readFileSync(path, 'utf8'))).toEqual({
+      version: 1,
+      deviceId: first,
+    })
   })
 
   it('accepts an explicit identity from the supervising host', () => {
@@ -31,6 +58,21 @@ describe('agentlet daemon identity', () => {
     })
   })
 
+  it('does not read or rewrite the persisted default for an explicit override', () => {
+    const path = identityPath()
+    expect(resolveAgentletId('custom-id', path)).toBe('custom-id')
+    expect(() => readFileSync(path)).toThrow()
+  })
+
+  it('fails instead of rotating a damaged persisted identity', () => {
+    const path = identityPath()
+    writeFileSync(path, '{"version":1,"deviceId":"broken"}')
+
+    expect(() => resolveAgentletId(undefined, path)).toThrow(
+      'Agentlet device identity is invalid',
+    )
+  })
+
   it.each(['0', '-1', '1.5', 'Infinity', '9007199254740992', '10agents'])(
     'rejects invalid max-agents value %s',
     (maxAgents) => {
diff --git a/external/agentlet/packages/local/tests/daemon-integration.test.ts b/external/agentlet/packages/local/tests/daemon-integration.test.ts
index b19197e07..8a80c99bc 100644
--- a/external/agentlet/packages/local/tests/daemon-integration.test.ts
+++ b/external/agentlet/packages/local/tests/daemon-integration.test.ts
@@ -1,4 +1,5 @@
 import { createServer, type Server } from 'node:http'
+import { arch, hostname, platform } from 'node:os'
 import { mkdirSync, rmSync, writeFileSync } from 'node:fs'
 import { randomUUID } from 'node:crypto'
 import { join } from 'node:path'
@@ -137,7 +138,7 @@ describe('agentlet daemon integration', () => {
     expect(controlHello).toMatchObject({
       agentletId: 'machine-a',
       agentletProfile: {
-        machine: { hostname: 'machine-a' },
+        machine: { hostname: hostname(), platform: platform(), arch: arch() },
         capabilities: { harnessDiscovery: { version: 1 } },
       },
     })
@@ -163,7 +164,10 @@ describe('agentlet daemon integration', () => {
     await waitUntil(() => sessionHello !== undefined)
     expect(sessionHello).toMatchObject({
       sessionId: 'native-bootstrap',
-      sessionProfile: { agentletId: 'machine-a', machine: { hostname: 'machine-a' } },
+      sessionProfile: {
+        agentletId: 'machine-a',
+        machine: { hostname: hostname(), platform: platform(), arch: arch() },
+      },
     })
     await waitUntil(() => sessionMessages.some(
       (message) => 'method' in message && message.method === 'session/update',
diff --git a/external/agentlet/packages/protocol/src/messages.ts b/external/agentlet/packages/protocol/src/messages.ts
index 28b5c7dab..4029320e1 100644
--- a/external/agentlet/packages/protocol/src/messages.ts
+++ b/external/agentlet/packages/protocol/src/messages.ts
@@ -15,6 +15,7 @@ export interface AgentletProfile {
   machine?: {
     hostname: string
     platform: string
+    arch: string
   }
 
   /** Agentlet capabilities */
@@ -72,6 +73,7 @@ export interface SessionProfile {
   machine?: {
     hostname: string
     platform: string
+    arch: string
   }
 
   /** Agentlet capabilities */
diff --git a/external/agentlet/spec/protocol.md b/external/agentlet/spec/protocol.md
index feb0d053b..77960208e 100644
--- a/external/agentlet/spec/protocol.md
+++ b/external/agentlet/spec/protocol.md
@@ -155,7 +155,7 @@ The daemon uses bounded FIFO buffers for ACP notifications emitted during bootst
 
 ## 7. Identity and placement
 
-The daemon's `agentletId` defaults to the operating-system hostname and can be supplied explicitly with `--agentlet-id`. The same identity appears in the control query, `agentlet/hello`, session query context, and `sessionProfile.agentletId`.
+The daemon's `agentletId` defaults to the persistent UUID in `~/.agentlet/device.json` and can be supplied explicitly with `--agentlet-id`. The identity file is created atomically on first use; an invalid existing file is an error rather than a reason to rotate identity. An explicit override does not rewrite the default identity. The same identity appears in the control query, `agentlet/hello`, session query context, and `sessionProfile.agentletId`; hostname, platform, and architecture are separate informational metadata.
 
 The native ACP `sessionId` is established by session bootstrap and is the routing identity for one session connection. The embedding control plane selects the target `agentletId`; the daemon does not choose workload placement.
 
diff --git a/packages/shared/src/types/api/acp.ts b/packages/shared/src/types/api/acp.ts
index 17ed9bd35..46b6bf1a0 100644
--- a/packages/shared/src/types/api/acp.ts
+++ b/packages/shared/src/types/api/acp.ts
@@ -163,8 +163,18 @@ export const acpAgentCliInfoSchema = z.object({
 export type AcpAgentCliInfo = z.infer<typeof acpAgentCliInfoSchema>;
 
 export const acpAgentCliQuerySchema = z
-  .object({ profileId: z.string().min(1).optional() })
-  .strict();
+  .object({
+    profileId: z.string().min(1).optional(),
+    agentletId: z.string().min(1).optional(),
+  })
+  .strict()
+  .refine(
+    (value) =>
+      Number(value.profileId !== undefined) +
+        Number(value.agentletId !== undefined) ===
+      1,
+    { message: 'Exactly one Profile or Agentlet target is required' },
+  );
 export type AcpAgentCliQuery = z.infer<typeof acpAgentCliQuerySchema>;
 
 /** Response body for `GET /api/acp/agent-cli`, including unavailable entries. */
@@ -576,9 +586,23 @@ export type AgentletConnectionCommandResponse = z.infer<
 >;
 
 /** Schema mirror of {@link AcpProfilesListResponse}. */
+export const connectedAgentletDeviceSchema = z.object({
+  agentletId: z.string().min(1),
+  hostname: z.string().min(1).optional(),
+  platform: z.string().min(1).optional(),
+  arch: z.string().min(1).optional(),
+  version: z.string().min(1),
+  connectedAt: z.iso.datetime(),
+  profileCount: z.number().int().nonnegative(),
+});
+export type ConnectedAgentletDevice = z.infer<
+  typeof connectedAgentletDeviceSchema
+>;
+
 export const acpProfilesListResponseSchema = z.object({
   profiles: z.array(agentProfileSchema),
   selectableProfileIds: z.array(z.string().min(1)),
+  connectedDevices: z.array(connectedAgentletDeviceSchema),
   agentlet: acpAgentletStatusSchema,
   agentDefaults: agentDefaultsSchema.optional(),
 });
diff --git a/packages/shared/src/types/api/agent-profile.test.ts b/packages/shared/src/types/api/agent-profile.test.ts
index 6d13d2498..cbdb8675d 100644
--- a/packages/shared/src/types/api/agent-profile.test.ts
+++ b/packages/shared/src/types/api/agent-profile.test.ts
@@ -9,6 +9,7 @@ import {
   agentProfileParamsSchema,
   agentProfileSchema,
   createAcpCommandProfileBodySchema,
+  createAcpProfileBodySchema,
   createAgentProfileBodySchema,
   patchAgentProfileBodySchema,
 } from './agent-profile.js';
@@ -40,6 +41,18 @@ describe('ordinary command Profile contracts', () => {
     ).toBe(false);
   });
 
+  it('requires explicit Agentlet placement for the ACP create API', () => {
+    expect(createAcpProfileBodySchema.safeParse(commandBody).success).toBe(
+      false,
+    );
+    expect(
+      createAcpProfileBodySchema.safeParse({
+        ...commandBody,
+        agentletId: 'device-1',
+      }).success,
+    ).toBe(true);
+  });
+
   it.each(['/work/project', 'C:\\work\\project', '\\\\host\\share'])(
     'accepts an absolute working directory: %s',
     (workingDirPath) => {
diff --git a/packages/shared/src/types/api/agent-profile.ts b/packages/shared/src/types/api/agent-profile.ts
index c483fd415..717227f23 100644
--- a/packages/shared/src/types/api/agent-profile.ts
+++ b/packages/shared/src/types/api/agent-profile.ts
@@ -133,7 +133,6 @@ export type CreateAcpCommandProfileBody = z.infer<
 
 export const createAcpProfileBodySchema = agentProfileSchema.omit({
   id: true,
-  agentletId: true,
   revision: true,
   executionRevision: true,
 });
@@ -160,9 +159,17 @@ export type PatchAgentProfileBody = z.infer<typeof patchAgentProfileBodySchema>;
 export const acpProfileLaunchPreviewBodySchema = z
   .object({
     profileId: trimmedString(255).optional(),
+    agentletId: trimmedString(255).optional(),
     launch: agentProfileSchema.shape.launch,
   })
-  .strict();
+  .strict()
+  .refine(
+    (value) =>
+      Number(value.profileId !== undefined) +
+        Number(value.agentletId !== undefined) ===
+      1,
+    { message: 'Exactly one Profile or Agentlet target is required' },
+  );
 export type AcpProfileLaunchPreviewBody = z.infer<
   typeof acpProfileLaunchPreviewBodySchema
 >;