ElevenLabs SDK — Field Guide
REV 2026-08-03PAGES 10STATUS CURRENT

SEC 06 / AUTH & CREDENTIALS

Auth & credential design

Every SDK in this ecosystem eventually runs into the same design question: where does the secret live? The answer is consistent across REST clients, browser agents, and mobile apps — permanent credentials stay on a server you control, and anything that reaches a client device is short-lived, scoped, and disposable.

Permanent API keys

Server-side REST clients authenticate with the ElevenLabs API key. Keys can be restricted by:

The key belongs only in a trusted server, secret manager, CI/CD secret store, or protected local environment, per the authentication docs.

Never put it in:

Ephemeral credentials for clients

For browser or mobile access, use an ephemeral credential instead of the permanent key:

The backend issuing this credential should:

Speech Engine JWT

Speech Engine authenticates connections through a short-lived JWT derived from the configured secret/API key relationship. The SDK verifies this by default — see the Speech Engine reference for the verification flow. Disabling verification should be limited to tightly isolated environments protected by network controls.

Client tools are untrusted input

Agent client tools allow the model or agent workflow to ask the client application to execute a function. Treat every tool invocation as untrusted input:

The existence of an agent instruction does not confer application authorization. A tool call is a request, not a credential — it still has to clear the same authorization checks any other user-triggered action would.

References