fix: fix non-serializable parameter of agent from toolUse block (#568)

* fix: fix non-serializable parameter of agent from toolUse block

* feat: Add configuration option to MCP Client for server init timeout (#657)

Co-authored-by: Harry Wilton <[email protected]>

* fix: Bedrock hang when exception occurs during message conversion (#643)

Previously (#642) bedrock would hang during message conversion because the exception was not being caught and thus the queue was always empty. Now all exceptions during conversion are caught

Co-authored-by: Mackenzie Zastrow <[email protected]>

* fix: only include parameters that defined in tool spec

---------

Co-authored-by: Jack Yuan <[email protected]>
Co-authored-by: fhwilton55 <[email protected]>
Co-authored-by: Harry Wilton <[email protected]>
Co-authored-by: Mackenzie Zastrow <[email protected]>
Co-authored-by: Mackenzie Zastrow <[email protected]>

Author: 4 people

src/strands/agent/agent.py

@@ -642,8 +642,11 @@ def _record_tool_execution(
             tool_result: The result returned by the tool.
             user_message_override: Optional custom message to include.
         """
+        # Filter tool input parameters to only include those defined in tool spec
+        filtered_input = self._filter_tool_parameters_for_recording(tool["name"], tool["input"])
+
         # Create user message describing the tool call
-        input_parameters = json.dumps(tool["input"], default=lambda o: f"<<non-serializable: {type(o).__qualname__}>>")
+        input_parameters = json.dumps(filtered_input, default=lambda o: f"<<non-serializable: {type(o).__qualname__}>>")
 
         user_msg_content: list[ContentBlock] = [
             {"text": (f"agent.tool.{tool['name']} direct tool call.\nInput parameters: {input_parameters}\n")}
@@ -653,14 +656,21 @@ def _record_tool_execution(
         if user_message_override:
             user_msg_content.insert(0, {"text": f"{user_message_override}\n"})
 
+        # Create filtered tool use for message history
+        filtered_tool: ToolUse = {
+            "toolUseId": tool["toolUseId"],
+            "name": tool["name"],
+            "input": filtered_input,
+        }
+
         # Create the message sequence
         user_msg: Message = {
             "role": "user",
             "content": user_msg_content,
         }
         tool_use_msg: Message = {
             "role": "assistant",
-            "content": [{"toolUse": tool}],
+            "content": [{"toolUse": filtered_tool}],
         }
         tool_result_msg: Message = {
             "role": "user",
@@ -717,6 +727,25 @@ def _end_agent_trace_span(
 
             self.tracer.end_agent_span(**trace_attributes)
 
+    def _filter_tool_parameters_for_recording(self, tool_name: str, input_params: dict[str, Any]) -> dict[str, Any]:
+        """Filter input parameters to only include those defined in the tool specification.
+
+        Args:
+            tool_name: Name of the tool to get specification for
+            input_params: Original input parameters
+
+        Returns:
+            Filtered parameters containing only those defined in tool spec
+        """
+        all_tools_config = self.tool_registry.get_all_tools_config()
+        tool_spec = all_tools_config.get(tool_name)
+
+        if not tool_spec or "inputSchema" not in tool_spec:
+            return input_params.copy()
+
+        properties = tool_spec["inputSchema"]["json"]["properties"]
+        return {k: v for k, v in input_params.items() if k in properties}
+
     def _append_message(self, message: Message) -> None:
         """Appends a message to the agent's list of messages and invokes the callbacks for the MessageCreatedEvent."""
         self.messages.append(message)

tests/strands/agent/test_agent.py

@@ -1738,99 +1738,7 @@ def test_agent_tool_non_serializable_parameter_filtering(agent, mock_randint):
     tool_call_text = user_message["content"][1]["text"]
     assert "agent.tool.tool_decorated direct tool call." in tool_call_text
     assert '"random_string": "test_value"' in tool_call_text
-    assert '"non_serializable_agent": "<<non-serializable: Agent>>"' in tool_call_text
-
-
-def test_agent_tool_multiple_non_serializable_types(agent, mock_randint):
-    """Test filtering of various non-serializable object types."""
-    mock_randint.return_value = 123
-
-    # Create various non-serializable objects
-    class CustomClass:
-        def __init__(self, value):
-            self.value = value
-
-    non_serializable_objects = {
-        "agent": Agent(),
-        "custom_object": CustomClass("test"),
-        "function": lambda x: x,
-        "set_object": {1, 2, 3},
-        "complex_number": 3 + 4j,
-        "serializable_string": "this_should_remain",
-        "serializable_number": 42,
-        "serializable_list": [1, 2, 3],
-        "serializable_dict": {"key": "value"},
-    }
-
-    # This should not crash
-    result = agent.tool.tool_decorated(random_string="test_filtering", **non_serializable_objects)
-
-    # Verify tool executed successfully
-    expected_result = {
-        "content": [{"text": "test_filtering"}],
-        "status": "success",
-        "toolUseId": "tooluse_tool_decorated_123",
-    }
-    assert result == expected_result
-
-    # Check the recorded message for proper parameter filtering
-    assert len(agent.messages) > 0
-    user_message = agent.messages[0]
-    tool_call_text = user_message["content"][0]["text"]
-
-    # Verify serializable objects remain unchanged
-    assert '"serializable_string": "this_should_remain"' in tool_call_text
-    assert '"serializable_number": 42' in tool_call_text
-    assert '"serializable_list": [1, 2, 3]' in tool_call_text
-    assert '"serializable_dict": {"key": "value"}' in tool_call_text
-
-    # Verify non-serializable objects are replaced with descriptive strings
-    assert '"agent": "<<non-serializable: Agent>>"' in tool_call_text
-    assert (
-        '"custom_object": "<<non-serializable: test_agent_tool_multiple_non_serializable_types.<locals>.CustomClass>>"'
-        in tool_call_text
-    )
-    assert '"function": "<<non-serializable: function>>"' in tool_call_text
-    assert '"set_object": "<<non-serializable: set>>"' in tool_call_text
-    assert '"complex_number": "<<non-serializable: complex>>"' in tool_call_text
-
-
-def test_agent_tool_serialization_edge_cases(agent, mock_randint):
-    """Test edge cases in parameter serialization filtering."""
-    mock_randint.return_value = 999
-
-    # Test with None values, empty containers, and nested structures
-    edge_case_params = {
-        "none_value": None,
-        "empty_list": [],
-        "empty_dict": {},
-        "nested_list_with_non_serializable": [1, 2, Agent()],  # This should be filtered out
-        "nested_dict_serializable": {"nested": {"key": "value"}},  # This should remain
-    }
-
-    result = agent.tool.tool_decorated(random_string="edge_cases", **edge_case_params)
-
-    # Verify successful execution
-    expected_result = {
-        "content": [{"text": "edge_cases"}],
-        "status": "success",
-        "toolUseId": "tooluse_tool_decorated_999",
-    }
-    assert result == expected_result
-
-    # Check parameter filtering in recorded message
-    assert len(agent.messages) > 0
-    user_message = agent.messages[0]
-    tool_call_text = user_message["content"][0]["text"]
-
-    # Verify serializable values remain
-    assert '"none_value": null' in tool_call_text
-    assert '"empty_list": []' in tool_call_text
-    assert '"empty_dict": {}' in tool_call_text
-    assert '"nested_dict_serializable": {"nested": {"key": "value"}}' in tool_call_text
-
-    # Verify non-serializable nested structure is replaced
-    assert '"nested_list_with_non_serializable": [1, 2, "<<non-serializable: Agent>>"]' in tool_call_text
+    assert '"non_serializable_agent": "<<non-serializable: Agent>>"' not in tool_call_text
 
 
 def test_agent_tool_no_non_serializable_parameters(agent, mock_randint):
@@ -1882,3 +1790,36 @@ def test_agent_tool_record_direct_tool_call_disabled_with_non_serializable(agent
 
     # Verify no messages were recorded
     assert len(agent.messages) == 0
+
+
+def test_agent_tool_call_parameter_filtering_integration(mock_randint):
+    """Test that tool calls properly filter parameters in message recording."""
+    mock_randint.return_value = 42
+
+    @strands.tool
+    def test_tool(action: str) -> str:
+        """Test tool with single parameter."""
+        return action
+
+    agent = Agent(tools=[test_tool])
+
+    # Call tool with extra non-spec parameters
+    result = agent.tool.test_tool(
+        action="test_value",
+        agent=agent,  # Should be filtered out
+        extra_param="filtered",  # Should be filtered out
+    )
+
+    # Verify tool executed successfully
+    assert result["status"] == "success"
+    assert result["content"] == [{"text": "test_value"}]
+
+    # Check that only spec parameters are recorded in message history
+    assert len(agent.messages) > 0
+    user_message = agent.messages[0]
+    tool_call_text = user_message["content"][0]["text"]
+
+    # Should only contain the 'action' parameter
+    assert '"action": "test_value"' in tool_call_text
+    assert '"agent"' not in tool_call_text
+    assert '"extra_param"' not in tool_call_text