Updates to make the library applicable for wider range of use cases, and more stable.

.github/workflows/flutter_packages.yaml

@@ -7,6 +7,7 @@
 name: Flutter GenUI CI
 
 on:
+  workflow_dispatch:
   push:
     branches:
       - main

README.md

@@ -122,6 +122,12 @@ graph TD
   genui_google_generative_ai --> genui
 ```
 
+## A2UI Support
+
+The Flutter Gen UI SDK uses the [A2UI protocol](https://a2ui.org) to represent UI content internally. The [genui_a2ui](packages/genui_a2ui/) package allows it to act as a renderer for UIs generated by an A2UI backend agent, similar to the [other A2UI renderers](https://github.com/google/A2UI/tree/main/renderers) which are maintained within the A2UI repository.
+
+The Flutter Gen UI SDK currently supports A2UI v0.8.
+
 ## Getting started
 
 See the [genui getting started guide](packages/genui/README.md#getting-started-with-genui).

packages/genai_primitives/example/main.dart

@@ -8,8 +8,26 @@ import 'dart:typed_data';
 import 'package:genai_primitives/genai_primitives.dart';
 import 'package:json_schema_builder/json_schema_builder.dart';
 
-void main() {
-  print('--- GenAI Primitives Example ---');
+enum Role { system, user, model }
+
+class ChatMessage {
+  final Role role;
+  final Message content;
+
+  const ChatMessage({required this.role, required this.content});
+
+  const ChatMessage.system(Message content)
+    : this(role: Role.system, content: content);
+
+  const ChatMessage.user(Message content)
+    : this(role: Role.user, content: content);
+
+  const ChatMessage.model(Message content)
+    : this(role: Role.model, content: content);
+}
+
+void main({void Function(Object? object) output = print}) {
+  output('--- GenAI Primitives Example ---');
 
   // 1. Define a Tool
   final ToolDefinition<Object> getWeatherTool = ToolDefinition(
@@ -29,92 +47,102 @@ void main() {
     ),
   );
 
-  print('\n[Tool Definition]');
-  print(const JsonEncoder.withIndent('  ').convert(getWeatherTool.toJson()));
+  output('\n[Tool Definition]');
+  output(const JsonEncoder.withIndent('  ').convert(getWeatherTool.toJson()));
 
   // 2. Create a conversation history
   final history = <ChatMessage>[
     // System message
     ChatMessage.system(
-      'You are a helpful weather assistant. '
-      'Use the get_weather tool when needed.',
+      Message.fromText(
+        'You are a helpful weather assistant. '
+        'Use the get_weather tool when needed.',
+      ),
     ),
 
     // User message asking for weather
-    ChatMessage.user('What is the weather in London?'),
+    ChatMessage.user(Message.fromText('What is the weather in London?')),
   ];
 
-  print('\n[Initial Conversation]');
+  output('\n[Initial Conversation]');
   for (final msg in history) {
-    print('${msg.role.name}: ${msg.text}');
+    output('${msg.role.name}: ${msg.content.text}');
   }
 
   // 3. Simulate Model Response with Tool Call
   final modelResponse = ChatMessage.model(
-    '', // Empty text for tool call
-    parts: [
-      const TextPart('Thinking: User wants weather for London...'),
-      const ToolPart.call(
-        callId: 'call_123',
-        toolName: 'get_weather',
-        arguments: {'location': 'London', 'unit': 'celsius'},
-      ),
-    ],
+    Message.fromText(
+      '', // Empty text for tool call
+      parts: [
+        const TextPart('Thinking: User wants weather for London...'),
+        const ToolPart.call(
+          callId: 'call_123',
+          toolName: 'get_weather',
+          arguments: {'location': 'London', 'unit': 'celsius'},
+        ),
+      ],
+    ),
   );
   history.add(modelResponse);
 
-  print('\n[Model Response with Tool Call]');
-  if (modelResponse.hasToolCalls) {
-    for (final ToolPart call in modelResponse.toolCalls) {
-      print('Tool Call: ${call.toolName}(${call.arguments})');
+  output('\n[Model Response with Tool Call]');
+  if (modelResponse.content.hasToolCalls) {
+    for (final ToolPart call in modelResponse.content.toolCalls) {
+      output('Tool Call: ${call.toolName}(${call.arguments})');
     }
   }
 
   // 4. Simulate Tool Execution & Result
   final toolResult = ChatMessage.user(
-    '', // User role is typically used for tool results in many APIs
-    parts: [
-      const ToolPart.result(
-        callId: 'call_123',
-        toolName: 'get_weather',
-        result: {'temperature': 15, 'condition': 'Cloudy'},
-      ),
-    ],
+    Message.fromText(
+      '', // User role is typically used for tool results in many APIs
+      parts: [
+        const ToolPart.result(
+          callId: 'call_123',
+          toolName: 'get_weather',
+          result: {'temperature': 15, 'condition': 'Cloudy'},
+        ),
+      ],
+    ),
   );
   history.add(toolResult);
 
-  print('\n[Tool Result]');
-  print('Result: ${toolResult.toolResults.first.result}');
+  output('\n[Tool Result]');
+  output('Result: ${toolResult.content.toolResults.first.result}');
 
   // 5. Simulate Final Model Response with Data (e.g. an image generated or
   //    returned)
   final finalResponse = ChatMessage.model(
-    'Here is a chart of the weather trend:',
-    parts: [
-      DataPart(
-        Uint8List.fromList([0x89, 0x50, 0x4E, 0x47]), // Fake PNG header
-        mimeType: 'image/png',
-        name: 'weather_chart.png',
-      ),
-    ],
+    Message.fromText(
+      'Here is a chart of the weather trend:',
+      parts: [
+        DataPart(
+          Uint8List.fromList([0x89, 0x50, 0x4E, 0x47]), // Fake PNG header
+          mimeType: 'image/png',
+          name: 'weather_chart.png',
+        ),
+      ],
+    ),
   );
   history.add(finalResponse);
 
-  print('\n[Final Model Response with Data]');
-  print('Text: ${finalResponse.text}');
-  if (finalResponse.parts.any((p) => p is DataPart)) {
-    final DataPart dataPart = finalResponse.parts.whereType<DataPart>().first;
-    print(
+  output('\n[Final Model Response with Data]');
+  output('Text: ${finalResponse.content.text}');
+  if (finalResponse.content.parts.any((p) => p is DataPart)) {
+    final DataPart dataPart = finalResponse.content.parts
+        .whereType<DataPart>()
+        .first;
+    output(
       'Attachment: ${dataPart.name} '
       '(${dataPart.mimeType}, ${dataPart.bytes.length} bytes)',
     );
   }
 
   // 6. Demonstrate JSON serialization of the whole history
-  print('\n[Full History JSON]');
-  print(
+  output('\n[Full History JSON]');
+  output(
     const JsonEncoder.withIndent(
       '  ',
-    ).convert(history.map((m) => m.toJson()).toList()),
+    ).convert(history.map((m) => m.content.toJson()).toList()),
   );
 }

packages/genai_primitives/lib/genai_primitives.dart

@@ -5,6 +5,6 @@
 /// A set of primitives for working with generative AI.
 library;
 
-export 'src/chat_message.dart';
+export 'src/message.dart';
 export 'src/message_parts.dart';
 export 'src/tool_definition.dart';