Generate OpenAPI mock

Generate deterministic example responses from an OpenAPI contract.

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ToolOpenAPI Mock Generator
Input
Output
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How it works

Operations and response schemas produce status codes, headers, and JSON bodies; explicit examples override generated primitive values. The output is static fixture data and does not implement authentication or business rules.

  • Success responses are the useful frontend default.
  • Error fixtures remain optional.

Worked example

Mock User Endpoint Response
Generate mock response data from an OpenAPI spec with a /users GET endpoint
Input
											{"openapi":"3.0.3","info":{"title":"API","version":"1.0.0"},"paths":{"/users":{"get":{"summary":"List users","responses":{"200":{"description":"OK","content":{"application/json":{"schema":{"type":"array","items":{"type":"object","properties":{"id":{"type":"integer"},"name":{"type":"string"},"email":{"type":"string","format":"email"}}}}}}}}}}}}
Output
												{
  "GET /users [200]": [
    {
      "id": 0,
      "name": "string",
      "email": "[email protected]"
    }
  ]
}

When to use this

A UI can render an endpoint before its service exists, while contract checks compare the fixture to the schema.

Edge cases

  • oneOf and discriminators need a branch choice.
  • A required header can be documented but not enforced by static data.
  • Random examples need a seed for stable snapshots.

References