Tool functions (sync or async, including Toolbox methods) that declare
a parameter named llm_tool_call are now passed the llm.ToolCall object
for the current invocation. The parameter is reserved: it is excluded
from the input schema exposed to the model and is only injected when
declared explicitly - a **kwargs catch-all does not receive it.
This lets tool implementations key external state against the unique
tool_call_id, e.g. for human-in-the-loop approval flows that need to
resume a specific tool call after the answer arrives.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Simon Willison
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