MailOptin · Authentication Profile

Mailoptin Authentication

Authentication

MailOptin declares 3 security scheme(s) across its OpenAPI definitions.

CompanyEmail MarketingMarketing AutomationLead GenerationWordPressNewslettersWebhookMCPPlugins
Methods: Schemes: 3 OAuth flows: API key in:

Security Schemes

oauth2
http
scheme: basic
X-WP-Nonce apiKey
· in: header ()

Source

Authentication Profile

mailoptin-authentication.yml Raw ↑
generated: '2026-08-12'
method: probed
source: >-
  https://mailoptin.io/.well-known/oauth-authorization-server,
  https://mailoptin.io/.well-known/oauth-protected-resource,
  https://mailoptin.io/wp-json/ (authentication block)
docs: https://mailoptin.io/docs/
note: >-
  There is no OpenAPI to derive from — derive-authentication.py found no spec. This
  profile is built entirely from documents mailoptin.io actually serves and from live
  401 responses observed on 2026-08-12.
schemes:
- id: oauth2_mcp
  type: oauth2
  applies_to: https://mailoptin.io/wp-json/mcp/mcp-oauth-server
  flow: authorization_code
  pkce: required
  pkce_methods: [S256]
  issuer: https://mailoptin.io
  authorization_url: https://mailoptin.io/oauth/authorize
  token_url: https://mailoptin.io/oauth/token
  revocation_url: https://mailoptin.io/oauth/revoke
  refresh: true
  scopes: [mcp]
  token_endpoint_auth_methods: [none]
  client_registration: client_id_metadata_document
  bearer_methods: [header]
  evidence:
    url: https://mailoptin.io/.well-known/oauth-authorization-server
    http_status: 200
- id: application_passwords
  type: http
  scheme: basic
  applies_to: https://mailoptin.io/wp-json/
  description: >-
    WordPress Application Passwords. The site's REST API root advertises the
    authorization endpoint in its `authentication` block. Per-user credentials issued
    from wp-admin; used with HTTP Basic.
  authorization_url: https://mailoptin.io/wp-admin/authorize-application.php
  evidence:
    url: https://mailoptin.io/wp-json/
    http_status: 200
- id: cookie_nonce
  type: apiKey
  in: header
  name: X-WP-Nonce
  applies_to: https://mailoptin.io/wp-json/
  description: >-
    WordPress cookie + nonce authentication for same-origin browser requests. Advertised
    in the CORS `access-control-allow-headers` response header alongside Authorization.
  evidence:
    url: https://mailoptin.io/wp-json/wp/v2/posts
    http_status: 200
anonymous_access:
  available: true
  note: >-
    Read-only content routes under /wp-json/wp/v2/ answer anonymously (posts returned
    x-wp-total 260 on 2026-08-12). Write routes, the Abilities API and both MCP servers
    are gated.
observed_denials:
- url: https://mailoptin.io/wp-json/mcp/mcp-oauth-server
  http_status: 401
  code: mcp_unauthorized
- url: https://mailoptin.io/wp-json/wp-abilities/v1/abilities
  http_status: 401
  code: rest_forbidden
product_authentication:
  note: >-
    The MailOptin PRODUCT is a self-hosted WordPress plugin. It authenticates OUTBOUND to
    60+ third-party email/CRM providers using each provider's own credentials (API keys,
    OAuth). Those are the third parties' schemes, not MailOptin's, and are not recorded
    here. MailOptin itself issues a license key, entered in wp-admin, for updates and
    premium features.

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