Public API
Error codes
Every Postify API error is RFC 9457 problem+json with a stable code. The full registry — what each of the 14 codes means, its HTTP status, and how to fix it.
Every /v1 error is RFC 9457 application/problem+json. Branch on the stable
code — the type URI resolves to one of these pages.
| Status | Code | Title |
|---|---|---|
| 400 | invalid_request | Invalid request |
| 400 | validation_failed | Request validation failed |
| 401 | authentication_required | Authentication required |
| 401 | invalid_api_key | Invalid API key |
| 403 | insufficient_scope | API credential lacks the required scope |
| 403 | feature_not_enabled | Feature not available on the current plan |
| 403 | dangerous_ops_disabled | Dangerous AI operations are disabled for this workspace |
| 404 | resource_not_found | Resource not found |
| 409 | resource_conflict | Resource state conflicts with the request |
| 409 | idempotency_in_progress | A request with this idempotency key is still in progress |
| 422 | idempotency_key_reused | Idempotency key reused with a different request body |
| 429 | rate_limited | Rate limit exceeded |
| 429 | quota_exhausted | Plan quota exhausted for this billing period |
| 500 | internal_error | Internal server error |
API documentation
Everything to build on the Postify REST API — 5-minute quickstart, API-key auth, RFC 9457 errors, cursor pagination, idempotency keys, rate limits, and all 17 operations with examples.
Webhooks
Subscribe to 5 workspace event types over Standard-Webhooks-signed HTTPS deliveries — envelope contract, HMAC verification with a runnable Node snippet, the 9-attempt retry schedule, and the failure ladder.