[BUG] AgentCoreCodeInterpreter's _create_tool_result stringifies binary content, breaking readFiles for binary files #370

return {
   "status": "success" if not is_error else "error",
   "content": [{"text": str(result.get("content"))}],  # Destroys binary
}

    def _create_tool_result(self, response: Dict[str, Any]) -> Dict[str, Any]:
        """Create tool result from response without stringifying resource content."""
        if "stream" in response:
            event_stream = response["stream"]
            for event in event_stream:
                if "result" in event:
                    result = event["result"]
                    content = result.get("content")
                    is_error = response.get("isError", False)
                    # Preserve content structure instead of stringifying
                    if isinstance(content, list):
                        return {
                            "status": "success" if not is_error else "error",
                            "content": content,
                        }
                    # Fall back to text wrapping for non-list content
                    return {
                        "status": "success" if not is_error else "error",
                        "content": [{"text": str(content)}],
                    }
            return {
                "status": "error",
                "content": [{"text": f"Failed to create tool result: {response}"}],
            }
        return response