Developer API testing workflow — curl, CORS and OpenAPI

Validate APIs locally: convert curl, test CORS, lint OpenAPI and mock JSON responses.

Frontend integration breaks on CORS misconfig, schema drift and wrong content types. A repeatable local checklist catches issues before staging deploys.

Use Tentaco API and Schema Studio modes together — no Postman cloud required for basic validation.

Steps

Paste OpenAPI YAML into OpenAPI Validator — fix syntax and reference errors.
Generate mock JSON from schemas with OpenAPI Mock for frontend stubs.
Convert curl one-liners to fetch() with curl Converter.
Probe CORS headers with CORS Tester from your target origin.
Validate sample responses against JSON Schema before merging to main.

Try it here

Interactive preview — runs in your browser.

Open in studio

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API Studio

Try the tool landing

Related guides

CORS Tester — debug cross-origin requests
Openapi Mock online — free in your browser
JSON Schema Validator — validate payloads