generated: '2026-09-10'
method: searched
source: 20 first-party OpenAPI contracts harvested from the Freddie Mac Developer Portal public API catalog,
  plus the portal's own Getting Started page and the OAuth error taxonomy the specs publish in their 401
  response descriptions.
summary:
  types:
  - http
schemes:
- name: bearerAuth
  type: http
  scheme: bearer
  bearerFormat: token
  sources:
  - openapi/freddie-mac-affordable-check-openapi.json
  - openapi/freddie-mac-beyond-ace-openapi.yaml
  - openapi/freddie-mac-cash-settlement-purchase-statement-openapi.json
  - openapi/freddie-mac-current-mortgage-snapshot-openapi.json
  - openapi/freddie-mac-data-share-bid-tape-openapi.json
  - openapi/freddie-mac-data-share-openapi.json
  - openapi/freddie-mac-guarantor-settlement-purchase-statement-openapi.json
  - openapi/freddie-mac-income-limits-openapi.json
  - openapi/freddie-mac-loan-closing-advisor-loan-submission-openapi.yaml
  - openapi/freddie-mac-loan-import-openapi.json
  - openapi/freddie-mac-loan-look-up-openapi.json
  - openapi/freddie-mac-property-insights-openapi.json
  - openapi/freddie-mac-resolve-liquidation-openapi.json
  - openapi/freddie-mac-resolve-retention-openapi.json
  - openapi/freddie-mac-resolve-valuation-pricing-openapi.json
  - openapi/freddie-mac-resolve-workout-options-openapi.json
- name: basicAuth
  type: http
  scheme: basic
  sources:
  - openapi/freddie-mac-cash-committing-openapi.json
  - openapi/freddie-mac-cash-pricing-openapi.json
  - openapi/freddie-mac-guarantor-committing-openapi.json
  - openapi/freddie-mac-guarantor-pricing-openapi.json
docs: https://sf.freddiemac.com/tools-learning/apis/getting-started-with-apis
profile:
  primary: OAuth 2.0 bearer token issued by the Freddie Mac Apigee gateway
  secondary: HTTP Basic on the four Loan Selling Advisor pricing/committing services (lassvcs-uat.fmrei.com/ESO/rest)
  credential_issuance: System-to-system API credentials are issued by a Freddie Mac representative to
    an organisation with counterparty (Seller/Servicer) or approved technology-partner status; there is
    no self-service signup. A Developer Administrator then creates an app in the Developer Portal and
    requests promotion to production.
  token_endpoint_published: false
  token_endpoint_note: 'No OAuth token endpoint, authorization-server metadata document or /.well-known/oauth-authorization-server
    is published anonymously. Probed 2026-09-10: api.freddiemac.com and api-test.freddiemac.com both 404
    that path; developer.freddiemac.com 401s it. The token URL is documented only inside the authenticated
    portal.'
  grant_evidence: 'The 401 response descriptions in every gateway-fronted spec enumerate an OAuth 2.0
    credential lifecycle: 401.001 invalid access token, 401.002 access token expired, 401.003 API product
    mismatch for token, 401.004 invalid API key (client ID), 401.005 invalid API key for resource, 401.006
    insufficient scope for application, 401.007 invalid username/password combination, 401.008 invalid
    refresh token, 401.009 invalid client secret, 401.010 refresh token expired. Client ID + client secret
    + refresh tokens + per-product scope is an Apigee OAuth 2.0 deployment; the username/password code
    additionally implies a resource-owner-password grant.'
  scopes_published: false
  scopes_note: Scope is enforced (401.006 'Insufficient scope for Application' and 401.003 'API Product
    mismatch for token') but no scope names are published in any spec or on any public page, so no scopes/
    artifact was written rather than an invented one.
vendor_headers:
- name: X-Lender-Id
  apis:
  - Beyond ACE
  - Property Insights
  note: lender identifier, sent on 11 operations
- name: X-Amc-Id
  apis:
  - Beyond ACE
  note: appraisal management company identifier
- name: X-LenderLoan-Id
  apis:
  - Beyond ACE
  note: lender loan identifier
- name: X-CSS-VENDOR-IDENTIFIER / -NAME / -SOFTWARE / -SOFTWARE-VERSION
  apis:
  - Cash Settlement Purchase Statement
  note: software-provider attribution headers required alongside the bearer token
- name: X-LIS-VENDOR-IDENTIFIER / -NAME / -SOFTWARE / -SOFTWARE-VERSION
  apis:
  - Loan Import
  note: software-provider attribution headers required alongside the bearer token