Skip to main content
Base URL:
Use the REST API when your software needs to read or change a Brein workspace directly. For an AI client, start with MCP and OAuth instead.

​
Authentication

Send a scoped API key in the x-api-key header:
A missing or invalid key returns 401. A valid key without permission for the workspace or action returns 403. Keep keys in your secret manager. Never commit them to source control or put them in customer-facing output.

​
Main resources

Every workspace route is scoped to the workspace in the URL. Do not assume that a route from one workspace can be used with another workspace’s credentials.

​
Usage and actions

Reads and contact actions have different cost rules. A successful response can include the current usage state. If an allowance is exhausted, the API returns an actionable 402 instead of silently continuing. Contact lookup is separate from saving a contact. Campaign creation is separate from campaign activation. A campaign is not sent until the required human confirmation succeeds.

​
Errors

See Errors for the shared response shape and common status codes.

​
Security

See Security for credential storage, workspace access, contact boundaries, and outbound email rules.