process_tool_call additional parameters (ToolDefinition & tool-ids)

[ChuckJonas]

Description

I'd like to propose adding additional parameters to the MCP process_tool_call hook:

1. ToolDefinition: Right now, we just get the tool_name, however, the ToolDefinition may contain information (particularly MCP tool metadata) useful in middleware scenario, additional validation, etc.

2. tool_call_id: This primarily would be useful to be able to pass along to MCP toolcall meta for log correlation... I actually assumed this was part of the MCP toolcall protocol, but it doesn't seem to be present from what I can tell.

References

https://ai.pydantic.dev/mcp/client/#tool-call-customization

[DouweM]

@ChuckJonas tool_call_id is already available on the RunContext that's passed into the process_tool_call function. What do you think of adding tool_def to RunContext as well?