ToolFn

Package: flyte.ai.agents

The tool under invocation, handed to a :data:ToolCallHandler.

Awaiting the instance runs the tool’s default behavior::

result = await tool_fn(**kwargs)

The attributes give a custom handler everything it needs to change that behavior without re-deriving it. The most useful are:

• :attr:target — the underlying @env.task template, plain callable, or LazyEntity (None for custom / MCP tools). Reach into it to, e.g., tool_fn.target.override(resources=...).aio(**kwargs).
• :attr:model — the owning agent’s model id, to pass to call_llm when the handler wants to consult the LLM.
• :attr:name / :attr:description / :attr:parameters — the tool’s LLM-facing metadata.

Parameters

class ToolFn(
    name: str,
    description: str,
    parameters: dict[str, Any],
    model: str,
    target: Any,
    source: str,
    _execute: _ToolExecutor,
)