How does my own app get an OAuth client ID for the Cirrux API?

An app that acts on behalf of whoever signs in to it, and needs their calendar, contacts, tasks, Drive or documents, uses OAuth. Registering such an app isn't self-service yet: email help@cirrux.co with

• the name people should see when they approve access,
• the redirect URLs your app uses, and
• the scopes it needs (see the scope list).

You get a client ID back. It's a public client: there is no client secret, so use PKCE. Access tokens last 15 minutes and refresh tokens 30 days.

You might not need OAuth

• Mail in your own workspace: a workspace API key reads, changes and sends mail in the mailboxes you pick, without anyone signing in. See letting a script read and send mail.
• An AI assistant such as Claude: connect it to the Cirrux MCP server. It registers itself, so you don't need a client ID. Tokens issued that way only work for MCP, not for the API.