SchemaSentry

SchemaSentry is a web app (with a lightweight CLI) that continuously checks whether your real API traffic still matches your published contract (OpenAPI/JSON Schema). Instead of only testing in CI with curated examples, it passively inspects sampled requests/responses from staging or production (via gateway logs or a sidecar) and flags breaking changes, undocumented fields, and risky behavior changes (status codes, nullability, enum expansion, pagination shape). It generates minimal reproducible examples and can auto-create regression tests and mocks from the observed traffic. The product is not trying to replace Postman or contract-testing suites; it’s a “drift detector” that catches what teams miss when multiple services and clients evolve independently. Expect some setup friction (permissions, data access, PII redaction), but once integrated it becomes a guardrail that reduces surprise outages and accelerates safe API evolution.