Caps
MCP tools/call uses the same Ultra tool caps as the Tools API, scoped to the OAuth access token for that session (not a shared account pool):
| Limit | Scope | Cap |
|---|---|---|
| Tool reads | Each OAuth access token | 60 / minute |
| Tool writes | Each OAuth access token | 60 / minute |
Active API tokens (liq_…) are capped at 10 per user (inventory for the Tools API, not MCP RPM). Failed Bearer authentications are limited to 20 / minute per client IP — see API errors & limits.
Over limit
Streamable HTTP may return 429 with Retry-After. JSON-RPC tools/call errors include retry guidance (retryAfterSeconds). Clients must back off.