# validation_failed — Postify API error

HTTP 400 · Request validation failed

This page is the resolution of the problem `type` URI `https://usepostify.com/docs/api/problems/validation-failed`.

The request parsed, but one or more fields failed schema validation. The `errors` array lists every failing field with a JSON Pointer (`pointer`), a field-level `code` and a message — fix them all in one pass.

## Common causes

- A required field is missing (e.g. variants on POST /v1/posts).
- A field is the wrong type or out of range (body over the length cap, scheduled_at not ISO-8601, an unknown webhook event type).
- Mutually exclusive fields sent together (e.g. draft plus scheduled_at).

## How to fix

- Iterate the `errors` array — each entry carries the field's `pointer` and what's wrong with it.
- Check the operation's request-body table in these docs for required fields, types, and limits.
- Send timestamps as full ISO-8601 UTC strings, e.g. 2026-08-01T09:00:00Z.

## Example response

```json
{
  "type": "https://usepostify.com/docs/api/problems/validation-failed",
  "title": "Request validation failed",
  "status": 400,
  "code": "validation_failed",
  "detail": "1 field failed validation.",
  "request_id": "req_6f1f8a2b40d34cd2a6f1e2c9b8d7a601"
}
```

## Related

- [Operation reference](https://usepostify.com/docs/api)
- [Interactive schema reference](https://usepostify.com/docs/api-reference)