Record output_tools as well

Author: mwildehahn

pydantic_ai_slim/pydantic_ai/_agent_graph.py

@@ -498,6 +498,7 @@ async def _prepare_request(
         # Populate tool tracking on the ModelRequest (the last request in the original history)
         self.request.function_tools = model_request_parameters.function_tools
         self.request.builtin_tools = model_request_parameters.builtin_tools
+        self.request.output_tools = model_request_parameters.output_tools
 
         model_settings = ctx.deps.model_settings
         usage = ctx.state.usage

pydantic_ai_slim/pydantic_ai/messages.py

@@ -963,6 +963,14 @@ class ModelRequest:
     Available for introspection during a run. This field is excluded from serialization.
     """
 
+    output_tools: Annotated[list[ToolDefinition] | None, pydantic.Field(exclude=True, repr=False)] = field(
+        default=None, repr=False
+    )
+    """Output tools that were available for this request.
+
+    Available for introspection during a run. This field is excluded from serialization.
+    """
+
     kind: Literal['request'] = 'request'
     """Message type identifier, this is available on all parts as a discriminator."""
 

tests/test_messages.py

@@ -612,25 +612,33 @@ def test_binary_content_validation_with_optional_identifier():
 
 
 def test_model_request_tool_tracking_excluded_from_serialization():
-    """Test that function_tools and builtin_tools are not serialized in the request."""
+    """Test that function, builtin, and output tools are not serialized in the request."""
     tool_def = ToolDefinition(
         name='test_tool',
         description='A test tool',
         parameters_json_schema={'type': 'object', 'properties': {}},
     )
+    output_tool_def = ToolDefinition(
+        name='request_output',
+        description='An output tool',
+        parameters_json_schema={'type': 'object', 'properties': {}},
+    )
 
     request = ModelRequest(
         parts=[UserPromptPart('test prompt')],
         instructions='test instructions',
         function_tools=[tool_def],
         builtin_tools=[ImageGenerationTool()],
+        output_tools=[output_tool_def],
     )
 
     # Verify the fields are accessible
     assert request.function_tools == [tool_def]
     assert request.builtin_tools == [ImageGenerationTool()]
+    assert request.output_tools == [output_tool_def]
 
     # Serialize - fields ARE excluded
     serialized = ModelMessagesTypeAdapter.dump_python([request], mode='json')
     assert 'function_tools' not in serialized[0]
     assert 'builtin_tools' not in serialized[0]
+    assert 'output_tools' not in serialized[0]