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x-fapi-auth-date

Authentication de facto — unregistered request reached by regulation

A reference entry. The registry facts and catalog measurements below are complete; the written guidance for this header has not been authored yet.

The x-fapi-auth-date HTTP header — authentication, declared by 88 providers in the API Evangelist catalog.

x-fapi-auth-date is authentication — Headers that carry who the caller is — credentials, tokens, keys, signatures of identity. The most declared category in the catalog and the most inconsistently spelled.

The registry

Not registered with IANA. It is a de facto or vendor field — real, widely used, and governed by nothing but convention.

In the catalog

Declared by 88 providers across 2,173 published specification files in the API Evangelist catalog, where it appears as a request header — sent by the client.

Reached by regulation

This header is mandated: the law, or a technical standard the law makes binding, names it directly. Only a credentialed caller can watch it in flight. The catalog can see that a contract declares it; it cannot see that a deployment honours it, and this site never claims otherwise.

Reached by these regulations

Catalogued at regulations.apievangelist.com, with the basis of each connection recorded rather than implied.

Governed by these rules

Machine-enforceable governance rules from rules.apievangelist.com that apply to this header when it appears in an OpenAPI.

OpenAPI Components Headers Error error

Utilizing the headers object in the centralized OpenAPI components library helps make headers reusable across API requests and responses

Guidance: Rate Limits →
OpenAPI Components Headers Info info

Utilizing the headers object in the centralized OpenAPI components library helps make headers reusable across API requests and responses

Guidance: Rate Limits →
OpenAPI Headers Hyphenated Pascal Case error

HTTP headers should follow Hyphenated-Pascal-Case naming convention for consistency and readability, such as Content-Type, X-Request-Id, or Accept-Language.

Guidance: Naming →
OpenAPI Security Schemes API Keys In Header Error error

Having components security schemes which possesses an api-key property that allows to configure how API keys are applied to operations have a in of header set.

Guidance: Security →
OpenAPI Security Schemes API Keys Info info

Having components security schemes which possesses an api-key property that allows to configure how API keys are applied to operations.

Guidance: Security →