> ## Documentation Index
> Fetch the complete documentation index at: https://cortex-foundation-add13747-droid-1a2462c9-cor-444-sanitize.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# upstream_failure

> An upstream service failed. HTTP 502.

# `upstream_failure`

|           |                                                            |
| --------- | ---------------------------------------------------------- |
| HTTP      | `502`                                                      |
| `code`    | `upstream_failure`                                         |
| `type`    | `https://docs.cortex.foundation/problems/upstream_failure` |
| Retryable | yes                                                        |

A dependency Cortex does not control failed. The `detail` names a product surface (the assistant, sign-in, audio), never a vendor.

```json theme={null}
{
  "type": "https://docs.cortex.foundation/problems/upstream_failure",
  "title": "An upstream service failed",
  "status": 502,
  "code": "upstream_failure",
  "request_id": "req_…"
}
```

See [Errors](/api/errors) for how to branch, and what not to render from `detail`.