Design a Tool Description for an AI Agent

    Help me write a tool (function) definition that an AI agent can call reliably.

What the tool does:
{{purpose}}

The inputs it needs, and what they mean:
{{inputs}}

What it returns, or does:
{{outputs}}

Produce:
1. A **tool name** that's specific and unambiguous (namespaced if it belongs with related tools).
2. A **description written for the model**: what the tool is for, when to use it and when NOT to, and any context the model can't infer (special formats, units, definitions of niche terms).
3. A **parameter schema** — for each parameter: a clear name (prefer `user_id` over `user`), its type, whether it's required, allowed values, and a one-line description. Use a strict schema.
4. **Failure modes** — the errors it can return, each with an actionable message, so the agent can recover rather than retry blindly.

If a parameter's meaning or the return shape is unclear from what I gave you, ask instead of guessing.