What is the standard format for API error responses?

Most REST APIs return a JSON object with at minimum an error code and a message field. RFC 7807 (Problem Details) is a widely adopted standard that adds type, title, status, and detail fields.

How should I handle JSON parse errors in API responses?

Always check the HTTP status code before calling response.json(). A 4xx or 5xx response might return HTML instead of JSON — use a try/catch around JSON.parse() and check Content-Type first.

Can I validate my API error format against a schema?

Yes. Use the Types and Schemas tab in JSONBlitz to generate a JSON Schema from your error response — use that schema to validate future responses programmatically.

How do I standardise API error responses across a team?

Paste one example error response into JSONBlitz, generate a JSON Schema, and share that schema as the contract for all error responses in your API.

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Frequently Asked Questions

What is the standard format for API error responses?: Most REST APIs return a JSON object with at minimum an error code and a message field. RFC 7807 (Problem Details) is a widely adopted standard that adds type, title, status, and detail fields.
How should I handle JSON parse errors in API responses?: Always check the HTTP status code before calling response.json(). A 4xx or 5xx response might return HTML instead of JSON — use a try/catch around JSON.parse() and check Content-Type first.
Can I validate my API error format against a schema?: Yes. Use the Types and Schemas tab in JSONBlitz to generate a JSON Schema from your error response — use that schema to validate future responses programmatically.
How do I standardise API error responses across a team?: Paste one example error response into JSONBlitz, generate a JSON Schema, and share that schema as the contract for all error responses in your API.