Authentication

API key headers, key management, and authentication errors.

Auth headers

Every authenticated request carries your API key in a header. Both conventions are accepted everywhere, on every endpoint. Use whichever your client library already sends:

curl https://api.kenpathlabs.com/v1/audio/speech \
  -H "Authorization: Bearer $SVARA_API_KEY" \
  ...

WebSocket connections authenticate the same way: send the header on the upgrade request. Discovery endpoints (/v1/voices, /v1/languages, /v1/models) are public and need no key.

API keys are server-side credentials. Don’t embed them in web or mobile clients. Proxy TTS calls through your backend, or scope a low-limit key per environment.

Managing keys

Keys are created and revoked in the console under API keys. Each key:

is shown in full exactly once, at creation (we store only a hash)
carries its own plan: concurrency, requests-per-minute, and monthly character limits are per key (see Rate limits)
reports its own usage; the usage page breaks down requests, characters, and audio minutes per key
can be revoked instantly, without affecting your other keys

A common pattern: one key per environment (prod, staging) or per integration, named accordingly, so usage attribution and revocation stay surgical.

Auth errors

Authentication failures return 401 with a structured body:

{
  "detail": {
    "status": "invalid_api_key",
    "message": "API key invalid or revoked."
  }
}

Parameter	Type	Default	Description
missing_api_key	401	-	No key found in either header. Send xi-api-key or Authorization: Bearer.
invalid_api_key	401	-	The key doesn’t exist or has been revoked.

These shapes match what the official ElevenLabs SDKs expect, so their built-in error handling works unchanged.