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ValidationCheck

Idempotency

Send an Idempotency-Key header (1–255 characters, for example a UUID or your own order ID) with any POST. For 24 hours:

  • Sending the same request with the same key returns the original response with Idempotent-Replay: true, and isn’t charged again.
  • Reusing the key with a different request returns 409 IDEMPOTENCY_CONFLICT.
  • Sending it again while the first request is still running also returns 409; retry shortly.

Errors that are safe to retry (429, 500, 503) aren’t stored, so a retry with the same key runs fresh.

Terminal window
curl https://api.validationcheck.net/v1/phone \
  -H "Authorization: Bearer $VC_KEY" \
  -H "Idempotency-Key: signup-8f14e45f" \
  -H "Content-Type: application/json" \
  -d '{"phone": "+1 415 555 2671"}'