> ## Documentation Index
> Fetch the complete documentation index at: https://docs.blockdb.io/llms.txt
> Use this file to discover all available pages before exploring further.

# API Error Codes

> HTTP statuses and error bodies returned by BlockDB REST endpoints.

### Format

```json theme={null}
{
  "error": {
    "code": "INVALID_ARGUMENT",
    "message": "from_block must be <= to_block",
    "details": { "field": "from_block" },
    "request_id": "req_01HXYZ..."
  }
}
```

### Common API Errors

| HTTP | Code               | Meaning                    | Action                                   |
| ---- | ------------------ | -------------------------- | ---------------------------------------- |
| 400  | INVALID\_ARGUMENT  | Body failed validation     | Fix the field noted in details           |
| 401  | UNAUTHENTICATED    | Missing/invalid token      | Send Authorization: Bearer token         |
| 403  | PERMISSION\_DENIED | Not allowed for plan/scope | Request access or adjust scope           |
| 404  | NOT\_FOUND         | Resource not found         | Verify endpoint or identifiers           |
| 409  | CONFLICT           | Mutually exclusive filters | Choose one filter set                    |
| 429  | RATE\_LIMITED      | Too many requests          | Backoff and retry; request higher limits |
| 500  | INTERNAL           | Unexpected error           | Retry with jitter; include request\_id   |
| 503  | UNAVAILABLE        | Temporary outage           | Retry after a short delay                |

<Note>
  Include the <code>request\_id</code> (if present), timestamp (UTC), and a minimal cURL reproduction when contacting support.
</Note>