Response code categories

  • 2xx: Success
  • 4xx: Client-side errors
  • 5xx: Server-side errors

Some 4xx errors include specific error codes for programmatic handling.

Common response codes

CodeStatusDescription
200OKRequest successful
400Bad RequestInvalid parameters
401UnauthorizedMissing or invalid API key
402Request FailedThe parameters were valid but the request failed.
403ForbiddenInsufficient permissions
404Not FoundResource doesn’t exist
409ConflictConflict with another request (perhaps due to using the same idempotent key).
429Too Many RequestsRate limit exceeded
500Server ErrorOpenPhone-side issue

For 429 errors, implement exponential backoff in your requests.