Authentication

Kaien API uses Bearer authentication by default:

Authorization: Bearer <YOUR_API_KEY>

OpenAI-compatible clients

OpenAI SDKs, Apifox, Postman, Bruno, Continue, and Cline generally support Bearer authentication.

curl https://kaienapi.com/v1/models \\
  -H "Authorization: Bearer <YOUR_API_KEY>"

Claude clients can send:

x-api-key: <YOUR_API_KEY>

Bearer authentication also works when the client allows custom request headers.

Gemini clients commonly support:

x-goog-api-key: <YOUR_API_KEY>

Some clients put the key in the query string:

?key=<YOUR_API_KEY>

Never put an API key in public frontend code.
Never commit a real key to Git.
Use separate keys for separate tools so they can be audited and revoked independently.
Review usage regularly and confirm that request sources are expected.