> For the complete documentation index, see [llms.txt](https://anyint.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://anyint.gitbook.io/docs/api-reference/errors-and-limits.md).

# errors and limits

## Common HTTP outcomes

| Code  | Meaning                                  | Typical action                                 |
| ----- | ---------------------------------------- | ---------------------------------------------- |
| `400` | Invalid request body or missing fields   | Validate payload shape before retrying         |
| `401` | Authentication failed                    | Check your API key and header style            |
| `403` | Access blocked by subscription or policy | Check entitlement, model access, or org policy |
| `429` | Limit reached                            | Back off, retry later, or upgrade limits       |
| `503` | Upstream temporarily unavailable         | Retry with backoff or use a fallback route     |

## Practical guidance

### Header mismatches

AnyInt publishes both bearer-style and provider-style auth patterns. If a request fails unexpectedly, verify that you used the right header family for the route you called.

### Model access issues

Before treating a response as a platform outage, confirm:

* the model ID exists
* the model is enabled for your account
* your subscription or key policy allows it

### Rate and usage limits

Limits can come from:

* subscription caps
* per-key restrictions
* team-level policies
* upstream provider throttling

### Async workflows

For video and AI Music routes, do not treat the initial task response as completion. Poll the task route or wait for a webhook before assuming the asset is ready.

## Family-specific notes

* Anthropic-compatible routes may return request-shape errors if `anthropic-version` is missing
* OpenAI-compatible chat returns stream chunks when `stream` is `true`
* AI Music has additional task and callback status codes documented in its own section