fix(openai): handle complex output types in responses API for openai 2 compat (#2253)

Signed-off-by: Adrian Cole <[email protected]>

Author: codefromthecrypt

python/instrumentation/openinference-instrumentation-openai/src/openinference/instrumentation/openai/_attributes/_responses_api.py

@@ -482,7 +482,9 @@ def _get_attributes_from_response_input_param_function_call_output(
         if (call_id := obj.get("call_id")) is not None:
             yield f"{prefix}{MessageAttributes.MESSAGE_TOOL_CALL_ID}", call_id
         if (output := obj.get("output")) is not None:
-            yield f"{prefix}{MessageAttributes.MESSAGE_CONTENT}", output
+            # output can be str or complex type - serialize complex types to JSON
+            output_value = output if isinstance(output, str) else safe_json_dumps(output)
+            yield f"{prefix}{MessageAttributes.MESSAGE_CONTENT}", output_value
 
     @classmethod
     @stop_on_exception
@@ -495,7 +497,9 @@ def _get_attributes_from_response_custom_tool_call_output_param(
         if (call_id := obj.get("call_id")) is not None:
             yield f"{prefix}{MessageAttributes.MESSAGE_TOOL_CALL_ID}", call_id
         if (output := obj.get("output")) is not None:
-            yield f"{prefix}{MessageAttributes.MESSAGE_CONTENT}", output
+            # output can be str or complex type - serialize complex types to JSON
+            output_value = output if isinstance(output, str) else safe_json_dumps(output)
+            yield f"{prefix}{MessageAttributes.MESSAGE_CONTENT}", output_value
 
     @classmethod
     @stop_on_exception