Authentication

How Rime’s MCP server resolves API keys: accepted headers, per-request handling, and which tools work without a key.

The MCP server is stateless and never stores your credentials; it reads your API key from each request and forwards it to the Rime API. Get a key from the API Tokens page; it’s the same key you use for the REST API.

Accepted headers

Two headers are accepted, checked in this order:

Header	Notes
Authorization: Bearer <key>	Preferred
X-Rime-Api-Key: <key>	Convenience alternative for clients that reserve the Authorization header

Tools that work without a key

Tool	API key
list_voices	Not required
get_voice_details	Not required
generate_integration	Not required
check_dictionary	Required
normalize_text	Required
synthesize_speech	Required

Calling a key-gated tool without a key returns a pointer to sign up rather than an error. Without a key you can still explore the catalog and generate integration code.

synthesize_speech calls the Rime API with your key, so generated samples consume credits like any other API request.