Tool Arguments Filtered by ADK Causing Tool Call Failures #32
Description
Tools produced by FrontendToolset() have a Signature that does not match the AG-UI Tool parameters.
The impact is that when the model calls the tool with the correct arguments, the FunctionTool.run_sync function filters out the LLM's arguments because they are not called "args". https://github.com/google/adk-python/blob/main/src/google/adk/tools/function_tool.py#L161-L169
It seems the official AG-UI library has patched this by overwriting the tool signature based on the AG-UI Tool Parameters:
https://github.com/ag-ui-protocol/ag-ui/blob/main/integrations/adk-middleware/python/src/ag_ui_adk/client_proxy_tool.py#L86-L88
My temporary fix for this is to modify the tool call arguments wrapping them in an "args" object using a before_tool_call hook in the agent.