# Support Tools

Small helper tools for calculation, secrets and guidance.

| Tool | Concurrent | Description |
|---|---|---|
| `calculate` | ✓ | Batch expression evaluator (arithmetic, unit conversion, currency arithmetic). Supports `sqrt`, `pow`, variadic `min`/`max`, `%`, `^`. Returns `{expression: result}`; a failed expression returns an error string instead of failing the whole call. It computes but never looks anything up — a rate or price comes from its own tool first and is passed in as a literal |
| `store_secret` | | Captures a value via masked input and writes directly to keychain — **the value never enters the LLM context, history, or logs**. The schema does **not** accept a `value` parameter; the agent only sees `name` + description. Fires on an auth failure (missing key, 401, 403, expired token): take the key name from the error, call this, then re-invoke the tool that failed. Max 2 rounds per tool per turn |