OpenAPI Testing

Turn Your OpenAPI Spec Into a Complete Test Suite

Import your OpenAPI or Swagger specification. Get CI-ready tests for every endpoint — with coverage tracking, contract validation, and self-healing built in.

Import Your OpenAPI Spec — FreeSee How It Works

The gap between your API spec and your tests

Spec exists, tests don't

You have a detailed OpenAPI spec but writing tests for every endpoint, method, and status code is a manual slog.

Spec changes break tests

Every time the spec evolves, existing tests need manual updates. The test suite drifts from reality.

Negative cases are skipped

Teams test happy paths but miss error scenarios, edge cases, and security checks that the spec actually defines.

Coverage is invisible

You can't see which parts of the spec have test coverage. Untested endpoints hide in plain sight.

Contract drift goes undetected

The API implementation slowly diverges from the spec. Nobody catches it until consumers break.

Multiple spec versions

Supporting OpenAPI 3.0, 3.1, and Swagger 2.0 across different services creates inconsistency.

Why generic API testing tools miss the point

Most tools treat your OpenAPI spec as a collection of endpoints. Total Shift Left treats it as a test blueprint.

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Manual test writing: Writing test cases endpoint-by-endpoint ignores the schema intelligence already in your spec.
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Postman import: Importing an OpenAPI spec into Postman creates basic requests — not tests. You still write all the assertions.
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Code-based frameworks: RestAssured, Playwright API, and similar tools require developers to write and maintain test code manually.
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Generic test generators: Most generators create shallow smoke tests. They don't understand schema constraints, enums, or nested objects.

From OpenAPI spec to full test coverage in four steps

1

Import your OpenAPI or Swagger spec

Upload a file, paste a URL, or connect your API gateway. Supports OpenAPI 3.0, 3.1, and Swagger 2.0.

2

AI generates comprehensive tests

Schema-aware AI creates tests for every endpoint: positive tests, negative tests, boundary values, auth flows, and error scenarios — all derived from your spec.

3

Review coverage and fill gaps

The coverage dashboard shows endpoint, method, status code, and parameter coverage. Generate tests for uncovered areas with one click.

4

Run in CI/CD with contract validation

Execute tests in your pipeline. Every run validates responses against the spec — catching contract drift before it reaches production.

3.x & 2.0

OpenAPI 3.0, 3.1, Swagger 2.0

85%

Coverage from first import

1 click

Fill coverage gaps

Every run

Contract validation

Frequently asked questions

  • Which OpenAPI versions are supported?
    Total Shift Left supports OpenAPI 3.0, OpenAPI 3.1, and Swagger 2.0 specifications. Upload a JSON or YAML file, paste a URL, or connect to your API gateway.
  • What types of tests are generated from the spec?
    The AI generates positive tests (valid requests), negative tests (invalid inputs, missing required fields), boundary value tests, authentication flows, error scenario tests, and security checks — all derived from the schema definitions in your spec.
  • How do tests stay in sync when the spec changes?
    Self-healing tests automatically adapt to non-breaking spec changes like new optional fields or updated descriptions. For breaking changes, the platform flags affected tests and suggests updates.
  • Can I import specs from Swagger Hub or API gateways?
    Yes. Import from any URL that serves an OpenAPI spec, including Swagger Hub, AWS API Gateway, Azure API Management, and Kong.
  • What is contract validation?
    Contract validation checks every API response against the schema in your OpenAPI spec. It catches type mismatches, missing required fields, unexpected values, and schema drift — automatically, on every test run.
  • Do I need to know OpenAPI to use this?
    You need an OpenAPI or Swagger spec for your API. If your team already has one, just import it. If not, many API frameworks can generate one from your code annotations.

Related

Postman Alternative →API Contract Testing →API Test Coverage →API Testing in CI/CD →Platform Overview →

Generate your first API test suite in minutes

Import your OpenAPI spec. Get CI-ready tests. Track coverage. No code, no credit card, 15-day free trial.

Import Your OpenAPI Spec — FreeSee How It Works