fix(mobile): show remote agent instructions from the registry (#8908)

After creating a remote (Builderbot) agent with instructions on mobile,
its profile said "Instructions aren't available on mobile for this
agent."

Two causes:
- Mobile called `list-agents` without `include_instructions: true`, so
registry rows had no `agent_instructions`. Desktop already sends this
flag.
- The profile read instructions only from published desktop agent
config, which remote agents don't have.

Now mobile requests instructions in `list-agents` (both the listing and
the post-create readback). For an agent in the active community owner's
registry listing, the profile shows the row's `agent_instructions`. Like
desktop, a missing field means "No instructions set." Desktop agents
keep the published-config path.

Because listings now carry instructions (up to 20,000 characters each),
`list-agents` gets a 4 MB response bound instead of 64 KB. The
delete-retry journal, which lives in plain preferences, drops
instructions before it's written.

### Before / after

iPhone SE, remote-agent-pilot community: profile of an agent just
created on mobile with the instructions "Reply in one short sentence."

| Before (main) | After (this PR) |
| --- | --- |
| <img
src="https://raw.githubusercontent.com/block/buzz/5d7333ea429e6c8c8aae93846d23c3a2bb9bda25/pr-8908--before-instructions.png"
width="300"> | <img
src="https://raw.githubusercontent.com/block/buzz/5d7333ea429e6c8c8aae93846d23c3a2bb9bda25/pr-8908--after-instructions.png"
width="300"> |

### Validation

- Extended `agents_sheet_test.dart`: the remote-agent case asserts the
`include_instructions` flag and that the profile shows the registry
text. It fails without the fix.
- New/extended tests for the larger `list-agents` bound and the retry
journal; each fails with its fix reverted.
- `just mobile-check` and the mobile test suite pass.
- iPhone SE (release build, remote-agent-pilot community): created an
agent with instructions on mobile, then opened its profile, which showed
them. Deleted the test agent afterward.

buzz-review-completed (manual testing waived by Tom)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Signed-off-by: Tom Brow <tomb@squareup.com>
Co-authored-by: Tom Brow <tomb@squareup.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

mobile/lib/features/agents/agent_identity_sections.dart

@@ -1,13 +1,15 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_hooks/flutter_hooks.dart';
+import 'package:hooks_riverpod/hooks_riverpod.dart';
 
+import '../../shared/community/community_provider.dart';
 import '../../shared/agents/remote_agents.dart';
 import '../../shared/theme/theme.dart';
 import '../../shared/widgets/app_list_card.dart';
 import 'agent_instructions.dart';
 
 /// The agent's instructions and management information in shared Settings cards.
-class AgentIdentitySections extends HookWidget {
+class AgentIdentitySections extends HookConsumerWidget {
   const AgentIdentitySections({
     required this.pubkey,
     required this.controller,
@@ -18,11 +20,19 @@ class AgentIdentitySections extends HookWidget {
   final RemoteAgentController controller;
 
   @override
-  Widget build(BuildContext context) {
+  Widget build(BuildContext context, WidgetRef ref) {
     useListenable(controller);
     final remote = controller.agents.any(
       (agent) => agent['agent_pubkey'] == pubkey,
     );
+    // Remote instructions come from the registry row, listed for the active
+    // community's owner only (as the agents page decides).
+    final owner = ref.watch(activeCommunityProvider).asData?.value?.pubkey;
+    final row = owner != null && controller.owner == owner
+        ? controller.agents
+              .where((agent) => agent['agent_pubkey'] == pubkey)
+              .firstOrNull
+        : null;
     return Column(
       crossAxisAlignment: CrossAxisAlignment.stretch,
       children: [
@@ -34,7 +44,7 @@ class AgentIdentitySections extends HookWidget {
               padding: const EdgeInsets.all(Grid.xs),
               child: SizedBox(
                 width: double.infinity,
-                child: AgentInstructions(pubkey: pubkey),
+                child: AgentInstructions(pubkey: pubkey, registryRow: row),
               ),
             ),
           ],

mobile/lib/features/agents/agent_instructions.dart

@@ -103,12 +103,25 @@ Future<String?> loadAgentInstructions(
 }
 
 /// Read-only instructions, with explicit unavailable and retry states.
+///
+/// A remote agent's instructions live in its Builderlab registry row, not in
+/// published config, so [registryRow] (when set) is the only source. Like
+/// desktop, an absent `agent_instructions` field means none are set, and a
+/// non-string value is an invalid listing.
 class AgentInstructions extends ConsumerWidget {
-  const AgentInstructions({required this.pubkey, super.key});
+  const AgentInstructions({required this.pubkey, this.registryRow, super.key});
   final String pubkey;
+  final Map<String, dynamic>? registryRow;
 
   @override
   Widget build(BuildContext context, WidgetRef ref) {
+    final row = registryRow;
+    if (row != null) {
+      final text = row['agent_instructions'] ?? '';
+      return text is String
+          ? _InstructionsText(text)
+          : const Text('Could not load instructions.');
+    }
     final instructions = ref.watch(agentInstructionsProvider(pubkey));
     return instructions.when(
       loading: () => const Center(
@@ -130,14 +143,25 @@ class AgentInstructions extends ConsumerWidget {
           ),
         ],
       ),
-      data: (text) => SelectableText(
-        text == null
-            ? 'Instructions aren’t available on mobile for this agent. View them on desktop.'
-            : text.trim().isEmpty
-            ? 'No instructions set.'
-            : text,
-        style: context.textTheme.bodyMedium,
-      ),
+      data: _InstructionsText.new,
+    );
+  }
+}
+
+class _InstructionsText extends StatelessWidget {
+  const _InstructionsText(this.text);
+  final String? text;
+
+  @override
+  Widget build(BuildContext context) {
+    final text = this.text;
+    return SelectableText(
+      text == null
+          ? 'Instructions aren’t available on mobile for this agent. View them on desktop.'
+          : text.trim().isEmpty
+          ? 'No instructions set.'
+          : text,
+      style: context.textTheme.bodyMedium,
     );
   }
 }

mobile/lib/shared/agents/remote_agents.dart

@@ -290,7 +290,9 @@ class RemoteAgentController extends ChangeNotifier {
       return;
     }
     await ensureBinding();
-    final result = await account.post('/v3/beekeeper/list-agents', {});
+    final result = await account.post('/v3/beekeeper/list-agents', {
+      'include_instructions': true,
+    });
     requireStatus(result, 'SUCCESS', 1);
     final rows = result['agents'] ?? [];
     if (rows is! List) throw StateError('Invalid agent listing.');
@@ -443,11 +445,9 @@ class RemoteAgentController extends ChangeNotifier {
     }, expectedSubject: subject);
     check();
     if (result['error'] != null) throw AccountFailure.rejected;
-    final readback = await account.post(
-      '/v3/beekeeper/list-agents',
-      {},
-      expectedSubject: subject,
-    );
+    final readback = await account.post('/v3/beekeeper/list-agents', {
+      'include_instructions': true,
+    }, expectedSubject: subject);
     check();
     requireStatus(readback, 'SUCCESS', 1);
     final rows = readback['agents'];
@@ -777,7 +777,10 @@ class RemoteAgentController extends ChangeNotifier {
     final retries = Map<String, dynamic>.from(
       jsonDecode(prefs.getString('$scope:delete-retries') ?? '{}') as Map,
     );
-    retries[pubkey] = agent;
+    // Instructions are private, and this retry journal is plain preferences;
+    // a retry needs only the row's identity.
+    retries[pubkey] = Map<String, dynamic>.from(agent)
+      ..remove('agent_instructions');
     if (!await prefs.setString('$scope:delete-retries', jsonEncode(retries))) {
       throw StateError('Could not save deletion retry. Retry Delete.');
     }

mobile/lib/shared/hosted/builderlab_account.dart

@@ -83,6 +83,12 @@ class BuilderlabAccountClient {
     '/v3/beekeeper/list-agents',
   };
 
+  /// Agent listings carry each agent's instructions (up to 20,000 characters
+  /// apiece), so they get room for many full agents; every other route keeps
+  /// the default bound.
+  static int _responseLimit(String path) =>
+      path == '/v3/beekeeper/list-agents' ? 4 * 1024 * 1024 : 65536;
+
   /// Sessions are scoped per origin so staging never reads production state.
   late final _storageKey =
       'buzz_hosted_session_${accountOrigin.host.replaceAll('.', '_')}_v1';
@@ -374,7 +380,11 @@ class BuilderlabAccountClient {
           );
         }
       }
-      final response = await boundedHttpResponse(_http, request);
+      final response = await boundedHttpResponse(
+        _http,
+        request,
+        maxBytes: _responseLimit(path),
+      );
       if (kDebugMode && response.statusCode >= 400) {
         debugPrint(
           'Builderlab ${accountOrigin.host} ${request.method} $path: HTTP ${response.statusCode} contentType=${response.headers['content-type']?.split(';').first}',

mobile/test/features/agents/agents_sheet_test.dart

@@ -203,6 +203,7 @@ void main() {
           'agent_pubkey': fakeAgent,
           'agent_id': 'remote-id',
           'agent_name': 'Scout',
+          'agent_instructions': 'Review carefully.',
         },
       ];
       await h.controller.run(h.controller.refresh);
@@ -213,6 +214,15 @@ void main() {
         find.textContaining('This agent runs on Builderbot.'),
         findsOneWidget,
       );
+      // Remote instructions come from the registry row, not published config.
+      expect(h.registry.bodies['/v3/beekeeper/list-agents'], {
+        'include_instructions': true,
+      });
+      expect(find.text('Review carefully.'), findsOneWidget);
+      expect(
+        find.textContaining('Instructions aren’t available'),
+        findsNothing,
+      );
       await tester.pumpAndSettle();
       await tester.ensureVisible(find.text('Delete agent'));
       expect(

mobile/test/shared/agents/remote_agents_test.dart

@@ -496,7 +496,11 @@ void main() {
       final registry = FakeRegistry(bound: fakeOwner.public);
       final controller = await _controller(registry);
       registry.listed = [
-        {'agent_pubkey': fakeAgent, 'agent_id': 'remote-id'},
+        {
+          'agent_pubkey': fakeAgent,
+          'agent_id': 'remote-id',
+          'agent_instructions': 'Private prompt.',
+        },
       ];
       await controller.run(controller.refresh);
       registry.calls.clear();
@@ -534,6 +538,12 @@ void main() {
       controller.rejectRemoval = true;
       expect(await remove(), isFalse);
       expect(registry.calls, ['remove-registration']);
+      // The retry journal is plain preferences, so it never holds the prompt.
+      final journal = (await SharedPreferences.getInstance()).getString(
+        '$_scope:delete-retries',
+      );
+      expect(journal, contains('remote-id'));
+      expect(journal, isNot(contains('Private prompt.')));
       registry.calls.clear();
       controller.rejectRemoval = false;
       expect(await remove(), isFalse);

mobile/test/shared/hosted/builderlab_account_test.dart

@@ -310,6 +310,34 @@ void main() {
     expect(await stored(), isNull);
   });
 
+  test('only agent listings may exceed the default response bound', () async {
+    // 100 KB: past the 64 KB default, as a few full-length instructions are.
+    final large = jsonEncode({'status': 1, 'padding': 'x' * 100000});
+    final client = BuilderlabAccountClient(
+      httpClient: MockClient((request) async {
+        if (request.url.path.endsWith('/exchange')) {
+          return http.Response(
+            jsonEncode({'session_credential': 'secret', 'expires_at': expiry}),
+            200,
+          );
+        }
+        if (request.url.path.contains('/beekeeper/')) {
+          return http.Response(large, 200);
+        }
+        return http.Response(
+          jsonEncode({'subject': 'account-1', 'expires_at': expiry}),
+          200,
+        );
+      }),
+    );
+    await client.exchange(code: 'one-use', verifier: verifier);
+    expect((await client.post('/v3/beekeeper/list-agents', {}))['status'], 1);
+    await expectLater(
+      client.post('/v3/beekeeper/get-model-catalog', {}),
+      throwsA(anything),
+    );
+  });
+
   test('authenticated post accepts only Buzz account routes', () async {
     final client = BuilderlabAccountClient(
       httpClient: MockClient((_) async => fail('no request expected')),