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POST
Start a sajn Login session
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Authorizations

Authorization
string
header
required

Personal API key, e.g. Authorization: Bearer sajn_sk_.... Not scope-limited — acts as the issuing user.

Headers

authorization
string
required

Bearer token for API authentication

Idempotency-Key
string

Makes retries safe. A retry with the same key and the same request replays the stored response for 24 hours (header Idempotent-Replayed: true); the same key with a different request returns 400.

Maximum string length: 255

Body

application/json

Body

clientId
string
required

The sajn Login client to authenticate against.

Minimum string length: 1
redirectUri
string
required

Where to send the user when authentication finishes. Must be registered on the client.

Minimum string length: 1
state
string

Opaque value echoed back on the redirect and in the session result.

Maximum string length: 512

Response

200

id
string
required
loginUrl
string
required

Open this in a browser or in-app browser to authenticate the user.

expiresAt
string
required