API contract tests vs reality
Contract tests are great at verifying that your implementation matches a written specification. They are not as good at catching silent divergence between the spec, the code, and real-world payloads.
Why contract tests can miss drift
- Fixtures reflect idealised payloads, not edge cases from production.
- Specs are not updated when services or clients evolve informally.
- Only a subset of fields and scenarios are covered by tests.
Bringing reality back into the loop
Capture real requests and responses from production or staging, then feed them into the HTTP Contract Drift Inspector alongside your contract examples. It shows you exactly where the shapes diverge.