Tool — Function Calling (client-side)

Define custom functions the agent can invoke. Your app executes the function and returns results. Runs expire 10 minutes after creation — return tool outputs promptly.

Security: Treat tool arguments as untrusted input. Don't pass secrets in tool output. Use strict=True for schema validation.

Not available via toolbox — function calling executes in the client process, so it's declared on the prompt agent, not in a toolbox version.

Prompt-agent SDK class

FunctionTool — wraps a Python callable; the SDK introspects its signature and docstring to build the schema sent to the model.

References

• Function Calling tool documentation
• agent-tools.md — tool index