feat: protect against anthropic nested tool args (#2250)

letta/interfaces/anthropic_streaming_interface.py

@@ -1,3 +1,4 @@
+import json
 from datetime import datetime, timezone
 from enum import Enum
 from typing import AsyncGenerator, List, Union
@@ -89,7 +90,13 @@ class AnthropicStreamingInterface:
 
     def get_tool_call_object(self) -> ToolCall:
         """Useful for agent loop"""
-        return ToolCall(id=self.tool_call_id, function=FunctionCall(arguments=self.accumulated_tool_call_args, name=self.tool_call_name))
+        # hack for tool rules
+        tool_input = json.loads(self.accumulated_tool_call_args)
+        if "id" in tool_input and tool_input["id"].startswith("toolu_") and "function" in tool_input:
+            arguments = str(json.dumps(tool_input["function"]["arguments"], indent=2))
+        else:
+            arguments = self.accumulated_tool_call_args
+        return ToolCall(id=self.tool_call_id, function=FunctionCall(arguments=arguments, name=self.tool_call_name))
 
     def _check_inner_thoughts_complete(self, combined_args: str) -> bool:
         """