specification: API Commons Authentication specificationVersion: '0.1' provider: Yahoo providerId: yahoo generated: '2026-08-28' method: searched source: >- https://developer.yahoo.com/oauth2/guide/ , https://api.login.yahoo.com/.well-known/openid-configuration , https://help.yahooinc.com/dsp-api/docs/authentication , https://help.yahooinc.com/dsp-api/docs/setup-access-guide , https://help.yahooinc.com/dsp-api/docs/authorization-and-headers , https://help.yahooinc.com/datax/docs/security-authentication docs: - https://developer.yahoo.com/oauth2/guide/ - https://help.yahooinc.com/dsp-api/docs/setup-access-guide - https://help.yahooinc.com/datax/docs/security-authentication description: >- Yahoo authenticates every public API surface with OAuth 2.0, but the flows differ sharply by product. Consumer-facing APIs (Fantasy Sports, Sign In With Yahoo) use the three-legged authorization-code flow against the Yahoo identity service at api.login.yahoo.com, which also publishes a full OpenID Connect Discovery document. The ad-tech APIs (DSP Traffic, DSP Reporting, DataX, Conversion API) use a two-legged client_credentials flow in which the client authenticates with a self-signed JWT and the resulting bearer token is presented in Yahoo's own X-Auth-Token / X-Auth-Method header pair rather than in Authorization. schemes: - id: yahoo-oauth2-authorization-code type: oauth2 flow: authorizationCode applies_to: - Yahoo Fantasy Sports API - Sign In With Yahoo authorization_endpoint: https://api.login.yahoo.com/oauth2/request_auth token_endpoint: https://api.login.yahoo.com/oauth2/get_token introspection_endpoint: https://api.login.yahoo.com/oauth2/introspect revocation_endpoint: https://api.login.yahoo.com/oauth2/revoke userinfo_endpoint: https://api.login.yahoo.com/openid/v1/userinfo jwks_uri: https://api.login.yahoo.com/openid/v1/certs grant_types: - authorization_code - refresh_token token_endpoint_auth_methods: - client_secret_basic - client_secret_post id_token_signing_algs: - ES256 - RS256 token_placement: 'Authorization: Bearer ' registration: https://developer.yahoo.com/apps/create/ docs: https://developer.yahoo.com/oauth2/guide/flows_authcode/ evidence: https://api.login.yahoo.com/.well-known/openid-configuration (HTTP 200) - id: yahoo-openid-connect type: openIdConnect applies_to: - Sign In With Yahoo issuer: https://api.login.yahoo.com discovery: https://api.login.yahoo.com/.well-known/openid-configuration subject_types: - public response_types: - code - token - id_token - code token - code id_token - token id_token - code token id_token response_modes: - query acr_values: - AAL1 - AAL2 claims: - aud - email - email_verified - birthdate - exp - family_name - given_name - iat - iss - locale - name - sub - auth_time claims_parameter_supported: false request_parameter_supported: false request_uri_parameter_supported: false docs: https://developer.yahoo.com/oauth2/guide/openid_connect/ evidence: https://api.login.yahoo.com/.well-known/openid-configuration (HTTP 200) - id: yahoo-dsp-client-credentials-jwt type: oauth2 flow: clientCredentials applies_to: - Yahoo DSP Traffic API - Yahoo DSP Reporting API - Yahoo Conversion API - Yahoo Ad Tech DataX API token_endpoint: https://id.b2b.yahooincapis.com/zts/v1/oauth2/token client_assertion: >- A JSON Web Token signed by the client identifies it to the token endpoint. DSP signs with HS256 using the client secret; DataX exchanges an RSA public key generated with OpenSSL and emailed to dataoperations@yahooinc.com during onboarding. token_placement: >- X-Auth-Method: OAuth2 and X-Auth-Token: headers, alongside Content-Type: application/json. The DSP APIs do NOT read the Authorization header. token_ttl_seconds: 21600 token_ttl_note: >- DataX raised the access-token TTL from 3600s to 21600s; clients are REQUIRED to cache and reuse tokens and read expires_in rather than assume the default. credential_issuance: >- Client ID and client secret are issued once, in the DSP UI (My Account > Activate), and are never redisplayed. A seat user must be created and API-enabled by a User Ops role holder before credentials can be generated. docs: https://help.yahooinc.com/dsp-api/docs/setup-access-guide evidence: https://help.yahooinc.com/dsp-api/docs/authorization-and-headers (HTTP 200) notes: - >- The Yahoo Conversion API requires its own separate direct OAuth 2.0 setup even for callers already authenticated against the DSP Traffic API. - >- Yahoo publishes no OpenAPI/Swagger description for any of these surfaces, so this profile is searched from the published documentation rather than derived from securitySchemes. - >- The DSP token endpoint id.b2b.yahooincapis.com/zts/v1 is an Athenz ZTS deployment; Athenz is Yahoo's own open-source service-authentication project (github.com/AthenZ). maintainers: - FN: Kin Lane email: kin@apievangelist.com