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

# Errors

> HTTP status codes and error response format.

## Error format

All errors follow this structure:

```json theme={null}
{
  "error": {
    "message": "Human-readable error description",
    "type": "error_type"
  }
}
```

## Status codes

| Code  | Type               | Description                    |
| ----- | ------------------ | ------------------------------ |
| `401` | `auth_error`       | Invalid or missing API key     |
| `402` | `billing_error`    | Insufficient balance           |
| `429` | `rate_limit_error` | Too many requests              |
| `502` | `upstream_error`   | LLM provider returned an error |
| `500` | `internal_error`   | Server error                   |

## Common errors and solutions

### 401 — Invalid API key

```json theme={null}
{"error": {"message": "Invalid API key", "type": "auth_error"}}
```

**Solutions:**

* Check that your key starts with `sk-occ-`
* Ensure the `Authorization` header format is `Bearer sk-occ-...`
* Verify the key hasn't been revoked in your dashboard

### 402 — Insufficient balance

```json theme={null}
{"error": {"message": "Insufficient balance", "type": "billing_error"}}
```

**Solution:** Add funds in the [dashboard](https://www.opencompress.ai/dashboard).

### 429 — Rate limit exceeded

```json theme={null}
{"error": {"message": "Rate limit exceeded", "type": "rate_limit_error"}}
```

**Solution:** Wait and retry with exponential backoff. Default limit is 60 requests/minute per key.

### 502 — Upstream error

```json theme={null}
{"error": {"message": "Upstream error: ...", "type": "upstream_error"}}
```

**Solutions:**

* Check if the model name is correct
* The LLM provider may be experiencing downtime
* For BYOK: verify your upstream API key is valid