Justt Authentication

generated: '2026-08-23'
method: searched
source: >-
  https://developers.justt.ai/docs/authentication,
  openapi/justt-rest-api-openapi-original.json,
  openapi/justt-pre-chargeback-alerts-openapi-original.json,
  asyncapi/justt-webhook-events-openapi-original.json,
  https://justt.ai/.well-known/oauth-authorization-server
docs: https://developers.justt.ai/docs/authentication
summary:
  types:
  - http
  - apiKey
  api_key_in:
  - header
  oauth2_flows: []
  primary: bearer API key in the Authorization header
schemes:
- name: bearer
  type: http
  scheme: bearer
  bearerFormat: JWT
  in: header
  parameter: Authorization
  format: 'Authorization: Bearer <api-key>'
  applies_to: Justt REST API, Pre-Chargeback Alerts API
  issuance: https://app.justt.ai/connect-psp/integration/api-integration
  environment_specific: true
  docs: https://developers.justt.ai/docs/authentication
  sources:
  - openapi/justt-rest-api-openapi-original.json
  - openapi/justt-pre-chargeback-alerts-openapi-original.json
  note: >-
    The spec declares bearerFormat: JWT, but the documentation consistently calls
    the credential an "API key" obtained from the hub rather than a token minted by
    a login flow. Treat it as a long-lived static bearer credential. Justt states
    the keys "come with a significant level of privilege" and warns against
    committing them.
- name: svix-signature
  type: apiKey
  in: header
  parameter: svix-signature
  applies_to: inbound webhooks (Justt -> merchant)
  direction: inbound
  algorithm: HMAC-SHA256
  sources:
  - asyncapi/justt-webhook-events-openapi-original.json
  note: >-
    This scheme secures the reverse direction: it authenticates Justt to the
    merchant's endpoint, not the merchant to Justt. The documented header triple is
    webhook-id / webhook-timestamp / webhook-signature (Standard Webhooks); the
    spec names the Svix header. Verify against the raw request body with a
    5-minute timestamp tolerance.
  docs: https://developers.justt.ai/docs/signature-verification
- name: mcp-oauth
  type: oauth2
  applies_to: the MCP endpoint at justt.ai/wp-json/mcp/mcp-oauth-server
  authorization_server: https://justt.ai
  authorization_endpoint: https://justt.ai/oauth/authorize
  token_endpoint: https://justt.ai/oauth/token
  revocation_endpoint: https://justt.ai/oauth/revoke
  grant_types: [authorization_code, refresh_token]
  pkce: S256
  scopes: [mcp]
  token_endpoint_auth_methods: [none]
  sources:
  - well-known/justt-oauth-authorization-server.json
  - well-known/justt-oauth-protected-resource.json
  note: >-
    Discovered by probe, not documented. This OAuth surface belongs to the MCP
    endpoint on the WordPress marketing host and has NOTHING to do with the
    chargeback API, which never uses OAuth. Recorded so an agent does not attempt
    an OAuth dance against api.justt.ai.
authorization_model:
  scopes: false
  roles: false
  tenancy:
    mechanism: reference-account-id request header
    docs: https://developers.justt.ai/docs/reference-accounts
    note: >-
      One key can address multiple merchant accounts by setting the
      reference-account-id header. There is no scope, permission or role system —
      a key that can read chargebacks can also accept them, which is the
      irreversible operation. Least-privilege is not expressible.
transport:
  https_required: true
  statement: >-
    "All our API calls must be transmitted over HTTPS. Calls made over plain HTTP
    will not succeed."
gaps:
- The OpenAPI declares securitySchemes but leaves the top-level `security` array
  empty and applies no security requirement to any operation, so a generated client
  will not send credentials by default even though every call requires them.
- No scopes, no per-key permissions, no key rotation or expiry policy is published.
- No OpenID Connect discovery on any Justt host.