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Is your OpenAPI spec actually test-ready?
Paste your OpenAPI or Swagger spec and see, endpoint by endpoint, whether it has enough error responses, security requirements, and request schemas for a test generator to work from — not just whether it's valid syntax.
Curious how your spec compares? We scored 2,518 public specs with this same methodology — 51% document zero error responses.
Paste or upload your OpenAPI / Swagger spec
Runs entirely in your browser. Your spec is never uploaded or stored anywhere.
Why these four things, specifically
Error responses
Without a documented 4xx/5xx response, a generator has nothing to assert against for the negative-test half of coverage — the half that actually catches regressions.
Security requirements
No security requirement means no basis to generate an authenticated-vs-unauthenticated test pair — one of the highest-value, most commonly-skipped test cases.
Request body schemas
A POST/PUT/PATCH with no schema means the generator can't construct a valid payload, let alone a boundary or malformed one.
Documentation completeness
operationId and parameter descriptions don't change what a generator can test, but they change whether the generated test names and assertions are legible to a human reviewing them.
Frequently asked questions
What does this tool actually check?
Four things a spec-driven test generator needs to produce a real test suite: whether each operation documents an error response (4xx/5xx), whether it declares a security requirement, whether POST/PUT/PATCH operations have a request body schema, and whether operations have an operationId and fully-described parameters. It is not a general OpenAPI linter — plenty of tools already validate schema syntax. This checks whether the spec has enough information to generate meaningful tests from.Does my spec get uploaded anywhere?
No. Parsing and scoring both run in your browser with JavaScript. Nothing is sent to a server, stored, or logged — you can disconnect from the network after the page loads and it still works.Does it support Swagger 2.0 as well as OpenAPI 3.x?
Yes, both. The tool detects which version you pasted from the openapi or swagger field at the top of the document and adjusts how it looks for request bodies accordingly (OpenAPI 3.x requestBody vs. Swagger 2.0 body parameters).My score is low — what do I do next?
The endpoint-by-endpoint table lists exactly what's missing per operation. Add the missing error responses, security requirements, and request schemas to your spec, then re-run the scorer. Once the gaps are filled, a spec-driven generator (including Total Shift Left's free tier) can produce real tests from it.Is the "estimated tests" number exact?
No — it's a simple, transparent estimate (roughly: one happy-path test per operation, plus one for each error-response family found, plus one for an auth-negative test where security is defined) meant to show relative improvement as you fill gaps, not a precise count of what any specific tool would generate.
Generate the tests this spec supports
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