From 133685f0bb52cd331d4bc970109c2596ebc70e7e Mon Sep 17 00:00:00 2001
From: Greg Spencer <gspencer@google.com>
Date: Thu, 14 May 2026 12:50:00 -0700
Subject: [PATCH 1/6] fix: surface catalog ID in PromptBuilder

---
 packages/genui/lib/src/facade/prompt_builder.dart     |  2 ++
 packages/genui/test/facade/prompt_builder_test.dart   | 11 +++++++++++
 .../all_operations_with_dataModel_false.txt           |  4 ++++
 .../all_operations_with_dataModel_true.txt            |  4 ++++
 .../create_and_update_with_dataModel_false.txt        |  4 ++++
 .../create_and_update_with_dataModel_true.txt         |  4 ++++
 .../create_only_with_dataModel_false.txt              |  4 ++++
 .../create_only_with_dataModel_true.txt               |  4 ++++
 .../update_only_with_dataModel_false.txt              |  4 ++++
 .../update_only_with_dataModel_true.txt               |  4 ++++
 10 files changed, 45 insertions(+)

diff --git a/packages/genui/lib/src/facade/prompt_builder.dart b/packages/genui/lib/src/facade/prompt_builder.dart
index 77ecada7c..1ca4a586c 100644
--- a/packages/genui/lib/src/facade/prompt_builder.dart
+++ b/packages/genui/lib/src/facade/prompt_builder.dart
@@ -366,6 +366,8 @@ final class _BasicPromptBuilder extends PromptBuilder {
     final fragments = <String>[
       ...systemPromptFragments,
       'Use the provided tools to respond to user using rich UI elements.',
+      if (catalog.catalogId != null)
+        'The active catalog ID is: "${catalog.catalogId}".',
       ...technicalPossibilities.systemPromptFragment(),
       ...catalog.systemPromptFragments,
       ...allowedOperations.systemPromptFragments,
diff --git a/packages/genui/test/facade/prompt_builder_test.dart b/packages/genui/test/facade/prompt_builder_test.dart
index dc573fdc5..954ae8e78 100644
--- a/packages/genui/test/facade/prompt_builder_test.dart
+++ b/packages/genui/test/facade/prompt_builder_test.dart
@@ -123,4 +123,15 @@ void main() {
       });
     }
   });
+
+  group('Catalog ID', () {
+    test('is surfaced in system prompt when provided', () {
+      final catalog = Catalog([
+        BasicCatalogItems.text,
+      ], catalogId: 'my_custom_catalog');
+      final builder = PromptBuilder.chat(catalog: catalog);
+      final String prompt = builder.systemPromptJoined();
+      expect(prompt, contains('The active catalog ID is: "my_custom_catalog"'));
+    });
+  });
 }
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_false.txt b/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_false.txt
index 55f3a5978..82a145d6c 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_false.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_false.txt
@@ -16,6 +16,10 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
+The active catalog ID is: "test_catalog".
+
+-------------------------------------
+
 IMPORTANT: You do not have the ability to execute code. If you need to perform calculations, do them yourself.
 
 -------------------------------------
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_true.txt b/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_true.txt
index 37e522f94..28d04fda5 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_true.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_true.txt
@@ -16,6 +16,10 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
+The active catalog ID is: "test_catalog".
+
+-------------------------------------
+
 IMPORTANT: You do not have the ability to execute code. If you need to perform calculations, do them yourself.
 
 -------------------------------------
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_false.txt b/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_false.txt
index 6dd36efd5..75f9e82d8 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_false.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_false.txt
@@ -16,6 +16,10 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
+The active catalog ID is: "test_catalog".
+
+-------------------------------------
+
 IMPORTANT: You do not have the ability to execute code. If you need to perform calculations, do them yourself.
 
 -------------------------------------
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_true.txt b/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_true.txt
index cdc0a60ad..233fb54d3 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_true.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_true.txt
@@ -16,6 +16,10 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
+The active catalog ID is: "test_catalog".
+
+-------------------------------------
+
 IMPORTANT: You do not have the ability to execute code. If you need to perform calculations, do them yourself.
 
 -------------------------------------
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_false.txt b/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_false.txt
index fda9dd04c..2cfdb9b42 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_false.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_false.txt
@@ -16,6 +16,10 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
+The active catalog ID is: "test_catalog".
+
+-------------------------------------
+
 IMPORTANT: You do not have the ability to execute code. If you need to perform calculations, do them yourself.
 
 -------------------------------------
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_true.txt b/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_true.txt
index 75f6319ff..ff26e08ad 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_true.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_true.txt
@@ -16,6 +16,10 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
+The active catalog ID is: "test_catalog".
+
+-------------------------------------
+
 IMPORTANT: You do not have the ability to execute code. If you need to perform calculations, do them yourself.
 
 -------------------------------------
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_false.txt b/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_false.txt
index ca6bf4884..effed272a 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_false.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_false.txt
@@ -16,6 +16,10 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
+The active catalog ID is: "test_catalog".
+
+-------------------------------------
+
 IMPORTANT: You do not have the ability to execute code. If you need to perform calculations, do them yourself.
 
 -------------------------------------
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_true.txt b/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_true.txt
index e04604e4f..a68662989 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_true.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_true.txt
@@ -16,6 +16,10 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
+The active catalog ID is: "test_catalog".
+
+-------------------------------------
+
 IMPORTANT: You do not have the ability to execute code. If you need to perform calculations, do them yourself.
 
 -------------------------------------

From 061a5bccc088839fb9e95e00e019d32ab15c4be6 Mon Sep 17 00:00:00 2001
From: Greg Spencer <gspencer@google.com>
Date: Thu, 14 May 2026 13:34:21 -0700
Subject: [PATCH 2/6] fix: sanitize catalog ID and add tests for null case in
 PromptBuilder

---
 .../genui/lib/src/facade/prompt_builder.dart  |  2 +-
 .../test/facade/prompt_builder_test.dart      | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/packages/genui/lib/src/facade/prompt_builder.dart b/packages/genui/lib/src/facade/prompt_builder.dart
index 1ca4a586c..9ddd6fa80 100644
--- a/packages/genui/lib/src/facade/prompt_builder.dart
+++ b/packages/genui/lib/src/facade/prompt_builder.dart
@@ -367,7 +367,7 @@ final class _BasicPromptBuilder extends PromptBuilder {
       ...systemPromptFragments,
       'Use the provided tools to respond to user using rich UI elements.',
       if (catalog.catalogId != null)
-        'The active catalog ID is: "${catalog.catalogId}".',
+        'The active catalog ID is: "${catalog.catalogId!.replaceAll('"', '\\"').replaceAll('\n', '\\n')}".',
       ...technicalPossibilities.systemPromptFragment(),
       ...catalog.systemPromptFragments,
       ...allowedOperations.systemPromptFragments,
diff --git a/packages/genui/test/facade/prompt_builder_test.dart b/packages/genui/test/facade/prompt_builder_test.dart
index 954ae8e78..bb4933f07 100644
--- a/packages/genui/test/facade/prompt_builder_test.dart
+++ b/packages/genui/test/facade/prompt_builder_test.dart
@@ -133,5 +133,24 @@ void main() {
       final String prompt = builder.systemPromptJoined();
       expect(prompt, contains('The active catalog ID is: "my_custom_catalog"'));
     });
+
+    test('is not surfaced in system prompt when not provided', () {
+      final catalog = Catalog([BasicCatalogItems.text]);
+      final builder = PromptBuilder.chat(catalog: catalog);
+      final String prompt = builder.systemPromptJoined();
+      expect(prompt, isNot(contains('The active catalog ID is:')));
+    });
+
+    test('is sanitized in system prompt', () {
+      final catalog = Catalog([
+        BasicCatalogItems.text,
+      ], catalogId: 'my_custom_\ncatalog"');
+      final builder = PromptBuilder.chat(catalog: catalog);
+      final String prompt = builder.systemPromptJoined();
+      expect(
+        prompt,
+        contains('The active catalog ID is: "my_custom_\\ncatalog\\"".'),
+      );
+    });
   });
 }

From ff3caa6a78b70311437023b3714ebcb2d29cde1f Mon Sep 17 00:00:00 2001
From: Greg Spencer <gspencer@google.com>
Date: Thu, 14 May 2026 18:00:13 -0700
Subject: [PATCH 3/6] Fix lint

---
 packages/genui/lib/src/facade/prompt_builder.dart | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/packages/genui/lib/src/facade/prompt_builder.dart b/packages/genui/lib/src/facade/prompt_builder.dart
index 9ddd6fa80..2dd8d0f54 100644
--- a/packages/genui/lib/src/facade/prompt_builder.dart
+++ b/packages/genui/lib/src/facade/prompt_builder.dart
@@ -363,11 +363,15 @@ final class _BasicPromptBuilder extends PromptBuilder {
       catalog,
     ).toJson(indent: '  ');
 
+    String? activeCatalogId = catalog.catalogId
+        ?.replaceAll('"', '\\"')
+        .replaceAll('\n', '\\n');
+
     final fragments = <String>[
       ...systemPromptFragments,
       'Use the provided tools to respond to user using rich UI elements.',
-      if (catalog.catalogId != null)
-        'The active catalog ID is: "${catalog.catalogId!.replaceAll('"', '\\"').replaceAll('\n', '\\n')}".',
+      if (activeCatalogId != null)
+        'The active catalog ID is: "$activeCatalogId".',
       ...technicalPossibilities.systemPromptFragment(),
       ...catalog.systemPromptFragments,
       ...allowedOperations.systemPromptFragments,

From 5d1502f2c152a794f1bbbfee27bada385b08897a Mon Sep 17 00:00:00 2001
From: Greg Spencer <gspencer@google.com>
Date: Fri, 15 May 2026 14:41:05 -0700
Subject: [PATCH 4/6] Fix formatting

---
 packages/genui/test/functions/format_string_test.dart | 1 +
 packages/genui/test/model/catalog_exception_test.dart | 1 +
 pubspec.yaml                                          | 3 +--
 3 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/packages/genui/test/functions/format_string_test.dart b/packages/genui/test/functions/format_string_test.dart
index 979af193d..144ffbf6c 100644
--- a/packages/genui/test/functions/format_string_test.dart
+++ b/packages/genui/test/functions/format_string_test.dart
@@ -8,6 +8,7 @@ import 'package:flutter_test/flutter_test.dart';
 import 'package:genui/src/catalog/basic_catalog.dart';
 import 'package:genui/src/functions/format_string.dart';
 import 'package:genui/src/model/data_model.dart';
+
 // import 'package:genui/src/primitives/simple_items.dart'; // Unused
 
 void main() {
diff --git a/packages/genui/test/model/catalog_exception_test.dart b/packages/genui/test/model/catalog_exception_test.dart
index 61a17fda1..98b982639 100644
--- a/packages/genui/test/model/catalog_exception_test.dart
+++ b/packages/genui/test/model/catalog_exception_test.dart
@@ -5,6 +5,7 @@
 import 'package:flutter/widgets.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:genui/genui.dart';
+
 // import 'package:genui/src/model/catalog.dart'; // Exceptions should be exported by genui.dart, but if not we might need this.
 // Assuming CatalogItemNotFoundException is exported or available.
 
diff --git a/pubspec.yaml b/pubspec.yaml
index 230463c2e..159ec24a7 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -15,13 +15,12 @@ workspace:
   - examples/composer
   - examples/e2e
   - examples/simple_chat
-  - examples/travel_app
   - examples/verdure/client
 
   - packages/a2ui_core
   - packages/genui
   - packages/genui_a2a
-  - packages/json_schema_builder  
+  - packages/json_schema_builder
 
   - tool/fix_copyright
   - tool/release

From 2a5d091e51fabfc4e5b1c0567f2f5d62ed0adc12 Mon Sep 17 00:00:00 2001
From: Greg Spencer <gspencer@google.com>
Date: Mon, 18 May 2026 11:01:09 -0700
Subject: [PATCH 5/6] fix(genui): sanitize catalogId and align prompt
 instructions with nullable active catalog ID

- Escape backslashes (`\`) and carriage returns (`\r`) inside `catalogId` in `prompt_builder.dart` to prevent quote escaping and line-break injections in system prompts.
- Update `SurfaceOperations` documentation and prompt instructions to refer conditionally to the active catalog ID ("if provided"), resolving a logic inconsistency when `catalogId` is null.
- Update test suite and regenerate prompt builder golden files to assert new sanitization patterns and conditional wording.
---
 packages/genui/lib/src/facade/prompt_builder.dart | 15 +++++++++------
 .../genui/test/facade/prompt_builder_test.dart    |  4 ++--
 .../all_operations_with_dataModel_false.txt       |  6 +++---
 .../all_operations_with_dataModel_true.txt        |  6 +++---
 .../create_and_update_with_dataModel_false.txt    |  6 +++---
 .../create_and_update_with_dataModel_true.txt     |  6 +++---
 .../create_only_with_dataModel_false.txt          |  6 +++---
 .../create_only_with_dataModel_true.txt           |  6 +++---
 .../update_only_with_dataModel_false.txt          |  2 +-
 .../update_only_with_dataModel_true.txt           |  2 +-
 10 files changed, 31 insertions(+), 28 deletions(-)

diff --git a/packages/genui/lib/src/facade/prompt_builder.dart b/packages/genui/lib/src/facade/prompt_builder.dart
index 2dd8d0f54..355861276 100644
--- a/packages/genui/lib/src/facade/prompt_builder.dart
+++ b/packages/genui/lib/src/facade/prompt_builder.dart
@@ -131,7 +131,7 @@ enum ProtocolMessages {
     explanation: 'Creates a new surface.',
     properties: '''
 Requires `surfaceId` (you must always use a unique ID for each created surface),
-`catalogId` (use the catalog ID provided in system instructions),
+`catalogId` (use the active catalog ID if provided in system instructions),
 and `sendDataModel: true`.
 ''',
     // TODO: figure out why we instruct AI to always set sendDataModel: true,
@@ -284,7 +284,7 @@ You can control the UI by outputting valid A2UI JSON messages wrapped in markdow
     if (create)
       '''
 To create a new UI:
-1. Output a ${ProtocolMessages.createSurface.tickedName} message with a unique `surfaceId` and `catalogId` (use the catalog ID provided in system instructions).
+1. Output a ${ProtocolMessages.createSurface.tickedName} message with a unique `surfaceId` and `catalogId` (use the active catalog ID if provided in system instructions).
 2. Output an ${ProtocolMessages.updateComponents.tickedName} message with the `surfaceId` and the component definitions.
 ''',
     if (!update)
@@ -363,15 +363,18 @@ final class _BasicPromptBuilder extends PromptBuilder {
       catalog,
     ).toJson(indent: '  ');
 
-    String? activeCatalogId = catalog.catalogId
-        ?.replaceAll('"', '\\"')
-        .replaceAll('\n', '\\n');
+    final String? activeCatalogId = catalog.catalogId
+        ?.replaceAll('\\', '\\\\')
+        .replaceAll('"', '\\"')
+        .replaceAll('\n', '\\n')
+        .replaceAll('\r', '\\r');
 
     final fragments = <String>[
       ...systemPromptFragments,
       'Use the provided tools to respond to user using rich UI elements.',
       if (activeCatalogId != null)
-        'The active catalog ID is: "$activeCatalogId".',
+        'The active catalog ID is: "$activeCatalogId". '
+            'You must use this catalog ID when creating surfaces.',
       ...technicalPossibilities.systemPromptFragment(),
       ...catalog.systemPromptFragments,
       ...allowedOperations.systemPromptFragments,
diff --git a/packages/genui/test/facade/prompt_builder_test.dart b/packages/genui/test/facade/prompt_builder_test.dart
index bb4933f07..9122c7a96 100644
--- a/packages/genui/test/facade/prompt_builder_test.dart
+++ b/packages/genui/test/facade/prompt_builder_test.dart
@@ -144,12 +144,12 @@ void main() {
     test('is sanitized in system prompt', () {
       final catalog = Catalog([
         BasicCatalogItems.text,
-      ], catalogId: 'my_custom_\ncatalog"');
+      ], catalogId: 'my_custom_\\\r\ncatalog"');
       final builder = PromptBuilder.chat(catalog: catalog);
       final String prompt = builder.systemPromptJoined();
       expect(
         prompt,
-        contains('The active catalog ID is: "my_custom_\\ncatalog\\"".'),
+        contains('The active catalog ID is: "my_custom_\\\\\\r\\ncatalog\\"".'),
       );
     });
   });
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_false.txt b/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_false.txt
index 82a145d6c..8e1a601d8 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_false.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_false.txt
@@ -16,7 +16,7 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
-The active catalog ID is: "test_catalog".
+The active catalog ID is: "test_catalog". You must use this catalog ID when creating surfaces.
 
 -------------------------------------
 
@@ -104,14 +104,14 @@ Supported messages are: `createSurface`, `updateComponents`, `deleteSurface`.
 Properties:
 
 - `createSurface`: Requires `surfaceId` (you must always use a unique ID for each created surface),
-`catalogId` (use the catalog ID provided in system instructions),
+`catalogId` (use the active catalog ID if provided in system instructions),
 and `sendDataModel: true`.
 - `updateComponents`: Requires `surfaceId` and a list of `components`.
 One component MUST have `id: "root"`.
 - `deleteSurface`: Requires `surfaceId`.
 
 To create a new UI:
-1. Output a `createSurface` message with a unique `surfaceId` and `catalogId` (use the catalog ID provided in system instructions).
+1. Output a `createSurface` message with a unique `surfaceId` and `catalogId` (use the active catalog ID if provided in system instructions).
 2. Output an `updateComponents` message with the `surfaceId` and the component definitions.
 
 To update an existing UI:
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_true.txt b/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_true.txt
index 28d04fda5..2a36a4df2 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_true.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_true.txt
@@ -16,7 +16,7 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
-The active catalog ID is: "test_catalog".
+The active catalog ID is: "test_catalog". You must use this catalog ID when creating surfaces.
 
 -------------------------------------
 
@@ -105,7 +105,7 @@ Supported messages are: `createSurface`, `updateComponents`, `deleteSurface`, `u
 Properties:
 
 - `createSurface`: Requires `surfaceId` (you must always use a unique ID for each created surface),
-`catalogId` (use the catalog ID provided in system instructions),
+`catalogId` (use the active catalog ID if provided in system instructions),
 and `sendDataModel: true`.
 - `updateComponents`: Requires `surfaceId` and a list of `components`.
 One component MUST have `id: "root"`.
@@ -113,7 +113,7 @@ One component MUST have `id: "root"`.
 - `updateDataModel`: Requires `surfaceId`, `path` and `value`.
 
 To create a new UI:
-1. Output a `createSurface` message with a unique `surfaceId` and `catalogId` (use the catalog ID provided in system instructions).
+1. Output a `createSurface` message with a unique `surfaceId` and `catalogId` (use the active catalog ID if provided in system instructions).
 2. Output an `updateComponents` message with the `surfaceId` and the component definitions.
 
 To update an existing UI:
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_false.txt b/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_false.txt
index 75f9e82d8..b657c8cb9 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_false.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_false.txt
@@ -16,7 +16,7 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
-The active catalog ID is: "test_catalog".
+The active catalog ID is: "test_catalog". You must use this catalog ID when creating surfaces.
 
 -------------------------------------
 
@@ -103,13 +103,13 @@ Supported messages are: `createSurface`, `updateComponents`.
 Properties:
 
 - `createSurface`: Requires `surfaceId` (you must always use a unique ID for each created surface),
-`catalogId` (use the catalog ID provided in system instructions),
+`catalogId` (use the active catalog ID if provided in system instructions),
 and `sendDataModel: true`.
 - `updateComponents`: Requires `surfaceId` and a list of `components`.
 One component MUST have `id: "root"`.
 
 To create a new UI:
-1. Output a `createSurface` message with a unique `surfaceId` and `catalogId` (use the catalog ID provided in system instructions).
+1. Output a `createSurface` message with a unique `surfaceId` and `catalogId` (use the active catalog ID if provided in system instructions).
 2. Output an `updateComponents` message with the `surfaceId` and the component definitions.
 
 To update an existing UI:
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_true.txt b/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_true.txt
index 233fb54d3..0d696fa02 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_true.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_true.txt
@@ -16,7 +16,7 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
-The active catalog ID is: "test_catalog".
+The active catalog ID is: "test_catalog". You must use this catalog ID when creating surfaces.
 
 -------------------------------------
 
@@ -104,14 +104,14 @@ Supported messages are: `createSurface`, `updateComponents`, `updateDataModel`.
 Properties:
 
 - `createSurface`: Requires `surfaceId` (you must always use a unique ID for each created surface),
-`catalogId` (use the catalog ID provided in system instructions),
+`catalogId` (use the active catalog ID if provided in system instructions),
 and `sendDataModel: true`.
 - `updateComponents`: Requires `surfaceId` and a list of `components`.
 One component MUST have `id: "root"`.
 - `updateDataModel`: Requires `surfaceId`, `path` and `value`.
 
 To create a new UI:
-1. Output a `createSurface` message with a unique `surfaceId` and `catalogId` (use the catalog ID provided in system instructions).
+1. Output a `createSurface` message with a unique `surfaceId` and `catalogId` (use the active catalog ID if provided in system instructions).
 2. Output an `updateComponents` message with the `surfaceId` and the component definitions.
 
 To update an existing UI:
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_false.txt b/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_false.txt
index 2cfdb9b42..f7f56748c 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_false.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_false.txt
@@ -16,7 +16,7 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
-The active catalog ID is: "test_catalog".
+The active catalog ID is: "test_catalog". You must use this catalog ID when creating surfaces.
 
 -------------------------------------
 
@@ -103,13 +103,13 @@ Supported messages are: `createSurface`, `updateComponents`.
 Properties:
 
 - `createSurface`: Requires `surfaceId` (you must always use a unique ID for each created surface),
-`catalogId` (use the catalog ID provided in system instructions),
+`catalogId` (use the active catalog ID if provided in system instructions),
 and `sendDataModel: true`.
 - `updateComponents`: Requires `surfaceId` and a list of `components`.
 One component MUST have `id: "root"`.
 
 To create a new UI:
-1. Output a `createSurface` message with a unique `surfaceId` and `catalogId` (use the catalog ID provided in system instructions).
+1. Output a `createSurface` message with a unique `surfaceId` and `catalogId` (use the active catalog ID if provided in system instructions).
 2. Output an `updateComponents` message with the `surfaceId` and the component definitions.
 
 IMPORTANT: DO NOT update or modify surfaces created in previous turns. If the UI needs to change, you MUST create a NEW surface with a new unique `surfaceId`. You may only use `updateComponents` to populate the components of a freshly created surface.
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_true.txt b/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_true.txt
index ff26e08ad..cb4b795d6 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_true.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_true.txt
@@ -16,7 +16,7 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
-The active catalog ID is: "test_catalog".
+The active catalog ID is: "test_catalog". You must use this catalog ID when creating surfaces.
 
 -------------------------------------
 
@@ -104,14 +104,14 @@ Supported messages are: `createSurface`, `updateComponents`, `updateDataModel`.
 Properties:
 
 - `createSurface`: Requires `surfaceId` (you must always use a unique ID for each created surface),
-`catalogId` (use the catalog ID provided in system instructions),
+`catalogId` (use the active catalog ID if provided in system instructions),
 and `sendDataModel: true`.
 - `updateComponents`: Requires `surfaceId` and a list of `components`.
 One component MUST have `id: "root"`.
 - `updateDataModel`: Requires `surfaceId`, `path` and `value`.
 
 To create a new UI:
-1. Output a `createSurface` message with a unique `surfaceId` and `catalogId` (use the catalog ID provided in system instructions).
+1. Output a `createSurface` message with a unique `surfaceId` and `catalogId` (use the active catalog ID if provided in system instructions).
 2. Output an `updateComponents` message with the `surfaceId` and the component definitions.
 
 IMPORTANT: DO NOT update or modify surfaces created in previous turns. If the UI needs to change, you MUST create a NEW surface with a new unique `surfaceId`. You may only use `updateComponents` to populate the components of a freshly created surface.
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_false.txt b/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_false.txt
index effed272a..c535e9b4d 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_false.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_false.txt
@@ -16,7 +16,7 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
-The active catalog ID is: "test_catalog".
+The active catalog ID is: "test_catalog". You must use this catalog ID when creating surfaces.
 
 -------------------------------------
 
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_true.txt b/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_true.txt
index a68662989..72224b23a 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_true.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_true.txt
@@ -16,7 +16,7 @@ Use the provided tools to respond to user using rich UI elements.
 
 -------------------------------------
 
-The active catalog ID is: "test_catalog".
+The active catalog ID is: "test_catalog". You must use this catalog ID when creating surfaces.
 
 -------------------------------------
 

From 5921e4374376043e7e4b2c9e7825a02c9f54e048 Mon Sep 17 00:00:00 2001
From: Greg Spencer <gspencer@google.com>
Date: Wed, 20 May 2026 16:56:15 -0700
Subject: [PATCH 6/6] fix(genui): treat catalogId as an arbitrary string
 instead of a URI

---
 .../linux/flutter/generated_plugins.cmake            |  1 +
 .../macos/Flutter/GeneratedPluginRegistrant.swift    |  2 +-
 .../composer/linux/flutter/generated_plugins.cmake   |  1 +
 .../macos/Flutter/GeneratedPluginRegistrant.swift    |  2 +-
 .../composer/windows/flutter/generated_plugins.cmake |  1 +
 .../linux/flutter/generated_plugins.cmake            |  1 +
 .../macos/Flutter/GeneratedPluginRegistrant.swift    |  2 +-
 .../windows/flutter/generated_plugins.cmake          |  1 +
 .../client/linux/flutter/generated_plugins.cmake     |  1 +
 .../macos/Flutter/GeneratedPluginRegistrant.swift    |  2 +-
 packages/genui/lib/src/facade/prompt_builder.dart    |  6 +-----
 packages/genui/lib/src/model/a2ui_schemas.dart       |  7 ++++++-
 packages/genui/test/facade/prompt_builder_test.dart  | 12 ------------
 .../all_operations_with_dataModel_false.txt          |  2 +-
 .../all_operations_with_dataModel_true.txt           |  2 +-
 .../create_and_update_with_dataModel_false.txt       |  2 +-
 .../create_and_update_with_dataModel_true.txt        |  2 +-
 .../create_only_with_dataModel_false.txt             |  2 +-
 .../create_only_with_dataModel_true.txt              |  2 +-
 .../update_only_with_dataModel_false.txt             |  2 +-
 .../update_only_with_dataModel_true.txt              |  2 +-
 21 files changed, 25 insertions(+), 30 deletions(-)

diff --git a/dev_tools/catalog_gallery/linux/flutter/generated_plugins.cmake b/dev_tools/catalog_gallery/linux/flutter/generated_plugins.cmake
index 8e2a1900c..a2eef970f 100644
--- a/dev_tools/catalog_gallery/linux/flutter/generated_plugins.cmake
+++ b/dev_tools/catalog_gallery/linux/flutter/generated_plugins.cmake
@@ -8,6 +8,7 @@ list(APPEND FLUTTER_PLUGIN_LIST
 )
 
 list(APPEND FLUTTER_FFI_PLUGIN_LIST
+  jni
 )
 
 set(PLUGIN_BUNDLED_LIBRARIES)
diff --git a/dev_tools/catalog_gallery/macos/Flutter/GeneratedPluginRegistrant.swift b/dev_tools/catalog_gallery/macos/Flutter/GeneratedPluginRegistrant.swift
index ad1073ab5..7b265476e 100644
--- a/dev_tools/catalog_gallery/macos/Flutter/GeneratedPluginRegistrant.swift
+++ b/dev_tools/catalog_gallery/macos/Flutter/GeneratedPluginRegistrant.swift
@@ -12,5 +12,5 @@ import video_player_avfoundation
 func RegisterGeneratedPlugins(registry: FlutterPluginRegistry) {
   AudioplayersDarwinPlugin.register(with: registry.registrar(forPlugin: "AudioplayersDarwinPlugin"))
   UrlLauncherPlugin.register(with: registry.registrar(forPlugin: "UrlLauncherPlugin"))
-  FVPVideoPlayerPlugin.register(with: registry.registrar(forPlugin: "FVPVideoPlayerPlugin"))
+  VideoPlayerPlugin.register(with: registry.registrar(forPlugin: "VideoPlayerPlugin"))
 }
diff --git a/dev_tools/composer/linux/flutter/generated_plugins.cmake b/dev_tools/composer/linux/flutter/generated_plugins.cmake
index c085ca836..a1bc1781f 100644
--- a/dev_tools/composer/linux/flutter/generated_plugins.cmake
+++ b/dev_tools/composer/linux/flutter/generated_plugins.cmake
@@ -10,6 +10,7 @@ list(APPEND FLUTTER_PLUGIN_LIST
 )
 
 list(APPEND FLUTTER_FFI_PLUGIN_LIST
+  jni
 )
 
 set(PLUGIN_BUNDLED_LIBRARIES)
diff --git a/dev_tools/composer/macos/Flutter/GeneratedPluginRegistrant.swift b/dev_tools/composer/macos/Flutter/GeneratedPluginRegistrant.swift
index 802a33c8d..4825c9db2 100644
--- a/dev_tools/composer/macos/Flutter/GeneratedPluginRegistrant.swift
+++ b/dev_tools/composer/macos/Flutter/GeneratedPluginRegistrant.swift
@@ -15,6 +15,6 @@ func RegisterGeneratedPlugins(registry: FlutterPluginRegistry) {
   AudioplayersDarwinPlugin.register(with: registry.registrar(forPlugin: "AudioplayersDarwinPlugin"))
   ScreenRetrieverMacosPlugin.register(with: registry.registrar(forPlugin: "ScreenRetrieverMacosPlugin"))
   UrlLauncherPlugin.register(with: registry.registrar(forPlugin: "UrlLauncherPlugin"))
-  FVPVideoPlayerPlugin.register(with: registry.registrar(forPlugin: "FVPVideoPlayerPlugin"))
+  VideoPlayerPlugin.register(with: registry.registrar(forPlugin: "VideoPlayerPlugin"))
   WindowManagerPlugin.register(with: registry.registrar(forPlugin: "WindowManagerPlugin"))
 }
diff --git a/dev_tools/composer/windows/flutter/generated_plugins.cmake b/dev_tools/composer/windows/flutter/generated_plugins.cmake
index f74fccabd..79fabcfb8 100644
--- a/dev_tools/composer/windows/flutter/generated_plugins.cmake
+++ b/dev_tools/composer/windows/flutter/generated_plugins.cmake
@@ -11,6 +11,7 @@ list(APPEND FLUTTER_PLUGIN_LIST
 )
 
 list(APPEND FLUTTER_FFI_PLUGIN_LIST
+  jni
 )
 
 set(PLUGIN_BUNDLED_LIBRARIES)
diff --git a/examples/simple_chat/linux/flutter/generated_plugins.cmake b/examples/simple_chat/linux/flutter/generated_plugins.cmake
index 8e2a1900c..a2eef970f 100644
--- a/examples/simple_chat/linux/flutter/generated_plugins.cmake
+++ b/examples/simple_chat/linux/flutter/generated_plugins.cmake
@@ -8,6 +8,7 @@ list(APPEND FLUTTER_PLUGIN_LIST
 )
 
 list(APPEND FLUTTER_FFI_PLUGIN_LIST
+  jni
 )
 
 set(PLUGIN_BUNDLED_LIBRARIES)
diff --git a/examples/simple_chat/macos/Flutter/GeneratedPluginRegistrant.swift b/examples/simple_chat/macos/Flutter/GeneratedPluginRegistrant.swift
index ad1073ab5..7b265476e 100644
--- a/examples/simple_chat/macos/Flutter/GeneratedPluginRegistrant.swift
+++ b/examples/simple_chat/macos/Flutter/GeneratedPluginRegistrant.swift
@@ -12,5 +12,5 @@ import video_player_avfoundation
 func RegisterGeneratedPlugins(registry: FlutterPluginRegistry) {
   AudioplayersDarwinPlugin.register(with: registry.registrar(forPlugin: "AudioplayersDarwinPlugin"))
   UrlLauncherPlugin.register(with: registry.registrar(forPlugin: "UrlLauncherPlugin"))
-  FVPVideoPlayerPlugin.register(with: registry.registrar(forPlugin: "FVPVideoPlayerPlugin"))
+  VideoPlayerPlugin.register(with: registry.registrar(forPlugin: "VideoPlayerPlugin"))
 }
diff --git a/examples/simple_chat/windows/flutter/generated_plugins.cmake b/examples/simple_chat/windows/flutter/generated_plugins.cmake
index 97b61367a..158064786 100644
--- a/examples/simple_chat/windows/flutter/generated_plugins.cmake
+++ b/examples/simple_chat/windows/flutter/generated_plugins.cmake
@@ -9,6 +9,7 @@ list(APPEND FLUTTER_PLUGIN_LIST
 )
 
 list(APPEND FLUTTER_FFI_PLUGIN_LIST
+  jni
 )
 
 set(PLUGIN_BUNDLED_LIBRARIES)
diff --git a/examples/verdure/client/linux/flutter/generated_plugins.cmake b/examples/verdure/client/linux/flutter/generated_plugins.cmake
index 04f81f4b4..ac700e247 100644
--- a/examples/verdure/client/linux/flutter/generated_plugins.cmake
+++ b/examples/verdure/client/linux/flutter/generated_plugins.cmake
@@ -9,6 +9,7 @@ list(APPEND FLUTTER_PLUGIN_LIST
 )
 
 list(APPEND FLUTTER_FFI_PLUGIN_LIST
+  jni
 )
 
 set(PLUGIN_BUNDLED_LIBRARIES)
diff --git a/examples/verdure/client/macos/Flutter/GeneratedPluginRegistrant.swift b/examples/verdure/client/macos/Flutter/GeneratedPluginRegistrant.swift
index 074b04b4c..46b142243 100644
--- a/examples/verdure/client/macos/Flutter/GeneratedPluginRegistrant.swift
+++ b/examples/verdure/client/macos/Flutter/GeneratedPluginRegistrant.swift
@@ -16,5 +16,5 @@ func RegisterGeneratedPlugins(registry: FlutterPluginRegistry) {
   DeviceInfoPlusMacosPlugin.register(with: registry.registrar(forPlugin: "DeviceInfoPlusMacosPlugin"))
   FileSelectorPlugin.register(with: registry.registrar(forPlugin: "FileSelectorPlugin"))
   UrlLauncherPlugin.register(with: registry.registrar(forPlugin: "UrlLauncherPlugin"))
-  FVPVideoPlayerPlugin.register(with: registry.registrar(forPlugin: "FVPVideoPlayerPlugin"))
+  VideoPlayerPlugin.register(with: registry.registrar(forPlugin: "VideoPlayerPlugin"))
 }
diff --git a/packages/genui/lib/src/facade/prompt_builder.dart b/packages/genui/lib/src/facade/prompt_builder.dart
index 355861276..9abb5211d 100644
--- a/packages/genui/lib/src/facade/prompt_builder.dart
+++ b/packages/genui/lib/src/facade/prompt_builder.dart
@@ -363,11 +363,7 @@ final class _BasicPromptBuilder extends PromptBuilder {
       catalog,
     ).toJson(indent: '  ');
 
-    final String? activeCatalogId = catalog.catalogId
-        ?.replaceAll('\\', '\\\\')
-        .replaceAll('"', '\\"')
-        .replaceAll('\n', '\\n')
-        .replaceAll('\r', '\\r');
+    final String? activeCatalogId = catalog.catalogId;
 
     final fragments = <String>[
       ...systemPromptFragments,
diff --git a/packages/genui/lib/src/model/a2ui_schemas.dart b/packages/genui/lib/src/model/a2ui_schemas.dart
index 29ba6feca..dbfc4835b 100644
--- a/packages/genui/lib/src/model/a2ui_schemas.dart
+++ b/packages/genui/lib/src/model/a2ui_schemas.dart
@@ -436,7 +436,12 @@ abstract final class A2uiSchemas {
         'the component tree.',
     properties: {
       surfaceIdKey: S.string(description: 'The unique ID for the surface.'),
-      'catalogId': S.string(description: 'The URI of the component catalog.'),
+      'catalogId': S.string(
+        description:
+            'A string that uniquely identifies this catalog. This is typically '
+            'a URI, but the URI is never accessed, only used as a unique '
+            'identifier.',
+      ),
       'theme': S.object(
         description: 'Theme parameters for the surface.',
         additionalProperties: true,
diff --git a/packages/genui/test/facade/prompt_builder_test.dart b/packages/genui/test/facade/prompt_builder_test.dart
index 9122c7a96..cbb04f1ef 100644
--- a/packages/genui/test/facade/prompt_builder_test.dart
+++ b/packages/genui/test/facade/prompt_builder_test.dart
@@ -140,17 +140,5 @@ void main() {
       final String prompt = builder.systemPromptJoined();
       expect(prompt, isNot(contains('The active catalog ID is:')));
     });
-
-    test('is sanitized in system prompt', () {
-      final catalog = Catalog([
-        BasicCatalogItems.text,
-      ], catalogId: 'my_custom_\\\r\ncatalog"');
-      final builder = PromptBuilder.chat(catalog: catalog);
-      final String prompt = builder.systemPromptJoined();
-      expect(
-        prompt,
-        contains('The active catalog ID is: "my_custom_\\\\\\r\\ncatalog\\"".'),
-      );
-    });
   });
 }
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_false.txt b/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_false.txt
index 8e1a601d8..3d27339c3 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_false.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_false.txt
@@ -151,7 +151,7 @@ When constructing UI, you must output a VALID A2UI JSON object representing one
             },
             "catalogId": {
               "type": "string",
-              "description": "The URI of the component catalog."
+              "description": "A string that uniquely identifies this catalog. It is recommended to prefix this with an internet domain that you own, to avoid conflicts e.g. 'mycompany.com:somecatalog'."
             },
             "theme": {
               "type": "object",
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_true.txt b/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_true.txt
index 2a36a4df2..7661b3a97 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_true.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/all_operations_with_dataModel_true.txt
@@ -153,7 +153,7 @@ When constructing UI, you must output a VALID A2UI JSON object representing one
             },
             "catalogId": {
               "type": "string",
-              "description": "The URI of the component catalog."
+              "description": "A string that uniquely identifies this catalog. It is recommended to prefix this with an internet domain that you own, to avoid conflicts e.g. 'mycompany.com:somecatalog'."
             },
             "theme": {
               "type": "object",
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_false.txt b/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_false.txt
index b657c8cb9..dd3adc395 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_false.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_false.txt
@@ -149,7 +149,7 @@ When constructing UI, you must output a VALID A2UI JSON object representing one
             },
             "catalogId": {
               "type": "string",
-              "description": "The URI of the component catalog."
+              "description": "A string that uniquely identifies this catalog. It is recommended to prefix this with an internet domain that you own, to avoid conflicts e.g. 'mycompany.com:somecatalog'."
             },
             "theme": {
               "type": "object",
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_true.txt b/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_true.txt
index 0d696fa02..c23b0e23b 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_true.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/create_and_update_with_dataModel_true.txt
@@ -151,7 +151,7 @@ When constructing UI, you must output a VALID A2UI JSON object representing one
             },
             "catalogId": {
               "type": "string",
-              "description": "The URI of the component catalog."
+              "description": "A string that uniquely identifies this catalog. It is recommended to prefix this with an internet domain that you own, to avoid conflicts e.g. 'mycompany.com:somecatalog'."
             },
             "theme": {
               "type": "object",
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_false.txt b/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_false.txt
index f7f56748c..d35089698 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_false.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_false.txt
@@ -148,7 +148,7 @@ When constructing UI, you must output a VALID A2UI JSON object representing one
             },
             "catalogId": {
               "type": "string",
-              "description": "The URI of the component catalog."
+              "description": "A string that uniquely identifies this catalog. It is recommended to prefix this with an internet domain that you own, to avoid conflicts e.g. 'mycompany.com:somecatalog'."
             },
             "theme": {
               "type": "object",
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_true.txt b/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_true.txt
index cb4b795d6..0ae7dfeed 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_true.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/create_only_with_dataModel_true.txt
@@ -150,7 +150,7 @@ When constructing UI, you must output a VALID A2UI JSON object representing one
             },
             "catalogId": {
               "type": "string",
-              "description": "The URI of the component catalog."
+              "description": "A string that uniquely identifies this catalog. It is recommended to prefix this with an internet domain that you own, to avoid conflicts e.g. 'mycompany.com:somecatalog'."
             },
             "theme": {
               "type": "object",
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_false.txt b/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_false.txt
index c535e9b4d..6f63a173a 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_false.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_false.txt
@@ -141,7 +141,7 @@ When constructing UI, you must output a VALID A2UI JSON object representing one
             },
             "catalogId": {
               "type": "string",
-              "description": "The URI of the component catalog."
+              "description": "A string that uniquely identifies this catalog. It is recommended to prefix this with an internet domain that you own, to avoid conflicts e.g. 'mycompany.com:somecatalog'."
             },
             "theme": {
               "type": "object",
diff --git a/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_true.txt b/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_true.txt
index 72224b23a..d85d3f55f 100644
--- a/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_true.txt
+++ b/packages/genui/test/facade/prompt_builder_test.golden/update_only_with_dataModel_true.txt
@@ -143,7 +143,7 @@ When constructing UI, you must output a VALID A2UI JSON object representing one
             },
             "catalogId": {
               "type": "string",
-              "description": "The URI of the component catalog."
+              "description": "A string that uniquely identifies this catalog. It is recommended to prefix this with an internet domain that you own, to avoid conflicts e.g. 'mycompany.com:somecatalog'."
             },
             "theme": {
               "type": "object",