generated: '2026-08-06'
method: searched
source: https://github.com/oapi-codegen/oapi-codegen/blob/main/docs/extensions.md
name: oapi-codegen OpenAPI specification extensions
summary: >-
  The vendor extension vocabulary oapi-codegen reads out of an OpenAPI 3.0/3.1
  document to steer Go code generation. These are the `x-` keys a spec author adds
  to schemas, properties, and types so the generator emits the Go shape they want.
  Captured verbatim from the project's published extensions reference.
version: v2.8.0
applies_to: OpenAPI 3.0 / 3.1 documents consumed by oapi-codegen
terms:
  - term: x-go-type
    scope: schema
    description: >-
      Override the Go type oapi-codegen determined the generated type should be.
  - term: x-go-type-import
    scope: schema
    description: >-
      Companion to x-go-type — declare the package import required by the
      overridden type (name + path).
  - term: x-go-type-skip-optional-pointer
    scope: schema / property
    description: >-
      Do not generate a pointer type for an optional struct field. The global
      equivalent is output-options.prefer-skip-optional-pointer.
  - term: x-go-name
    scope: schema / property
    description: Override the generated Go name of a field or a type.
  - term: x-go-type-name
    scope: schema
    description: >-
      Override the generated Go name of a type only (unlike x-go-name, which also
      applies to struct fields).
  - term: x-omitempty
    scope: property
    description: >-
      Force the JSON struct tag `omitempty` onto a field that would not get one by
      default (e.g. a required field).
  - term: x-omitzero
    scope: property
    description: >-
      Force the JSON struct tag `omitzero` onto a field. Requires Go 1.24+.
  - term: x-go-json-ignore
    scope: property
    description: Omit the field from JSON marshaling/unmarshaling.
  - term: x-oapi-codegen-extra-tags
    scope: property
    description: >-
      Emit arbitrary additional struct tags on the generated field (validation,
      database, logging tags, etc.).
  - term: x-enum-varnames
    scope: schema (enum)
    description: Override the generated Go variable names for enum constants.
  - term: x-enumNames
    scope: schema (enum)
    description: Alias of x-enum-varnames.
  - term: x-deprecated-reason
    scope: schema
    description: >-
      Add a GoDoc `Deprecated:` warning to the generated type, carrying the reason.
  - term: x-order
    scope: property
    description: >-
      Explicitly order generated struct fields. 1-indexed; `x-order: 0` is invalid.
  - term: x-oapi-codegen-only-honour-go-name
    scope: schema / property
    description: >-
      Only honour x-go-name when generating field names, bypassing the generator's
      clash-avoidance and Go-identifier rewriting.
x-evidence:
  fetched: '2026-08-06'
  url: https://raw.githubusercontent.com/oapi-codegen/oapi-codegen/main/docs/extensions.md
  http_status: 200