api-contract

To prevent breaking changes in your API, you can validate route modifications by diffing proposed updates against current parameters, response shapes, and status codes to identify backward-incompatible modifications before deployment.

API contract validation documents existing endpoint parameters and response types, then compares proposed changes to flag breaking modifications and assess which clients might be affected by the updated API structure.

You can validate Zod schemas and API route files by comparing the proposed schema modifications against documented response types and current endpoint contracts to detect breaking changes and generate migration strategies.

Yes, API contract validation works with existing endpoint definitions by documenting current parameters and response shapes from your route files, then diffing proposed changes to ensure new optional fields do not break current client integrations.

The best way to add optional fields safely is to validate the API contract by diffing the proposed response shape changes against the current structure, which flags potential breaking modifications and provides migration strategies for affected clients.

Contract diffing for API breaking change detection is limited to documented parameters, response shapes, and status codes, meaning it may not catch runtime breaking changes or undocumented behaviors outside the explicit API contract.