Validate OpenAPI

Validate an OpenAPI document’s structure, references, and operation contracts.

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ToolOpenAPI Validator
Input
Output
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Preview

How it works

The document is checked for top-level fields, paths, operations, parameter placement, schema references, responses, and components. Findings are reported without serving or calling endpoints.

  • Structural errors come before style warnings.
  • Valid contracts can then feed docs and client generators.

Worked example

Validate Pet Store Spec
Check an OpenAPI 3.0 spec for errors and warnings
Input
											{"openapi":"3.0.3","info":{"title":"Pet Store","version":"1.0.0"},"paths":{"/pets":{"get":{"summary":"List pets","responses":{"200":{"description":"OK"}}}}}}
Output
												Valid: yes
Version: 3.0.3
Errors: none
Warnings: Missing recommended 'info.description', Missing recommended 'info.contact', Missing 'operationId' in GET /pets, Missing 'servers' array (recommended for OpenAPI 3.x)

STATS
Paths: 1
Operations: 1
Schemas: 0
Parameters: 0

When to use this

CI, gateways, and client generators validate OpenAPI contracts.

Edge cases

  • A path variable needs a matching required path parameter.
  • A 204 response can omit content while a JSON success usually cannot.
  • A dangling $ref invalidates its operation.

References