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This rule belongs to the openapi-v3-standards-linting ruleset and states that:

The response headers list can contain the expected headers that can be received as part of the response. There can only be a single entry for each header in this list. Since the header names are case insensitive as per RFC7230 they will be compared accordingly.

Maximum SeverityWarning
MessageA definition for this header parameter already exists.
Rule SystemSemantic
Broad CategoryResponses
Products ImpactedAPI Transformer, Code Generation, Developer Experience Portal
Tagsopenapi3 openapi standards semantic linting name header response

Suggested Fixes

  • Remove duplicate entries for the header in the list.
  • Header names are compared in a case-insensitive manner. This means that headers named content-type and Content-Type are considered equal.

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