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

# Errors

> The single error envelope and what each status means.

Every error — from the gateway or from Mithril's core — renders as one shape:

```json theme={null}
{
  "error": {
    "code": "risk_limit_exceeded",
    "message": "order notional 40000 exceeds max_order_notional 250",
    "request_id": "req_9f3a..."
  }
}
```

* **`code`** — a stable, machine-readable string you can branch on.
* **`message`** — a human-readable explanation. Safe to log and show.
* **`request_id`** — include this when you contact support; it ties your request
  to our logs.

## Status codes

| Status | Meaning                                            | Typical `code`               |
| ------ | -------------------------------------------------- | ---------------------------- |
| `400`  | Malformed request or missing required field/header | `bad_request`                |
| `401`  | Missing, invalid, or revoked API key               | `unauthorized`               |
| `403`  | Authenticated but not allowed                      | `forbidden`                  |
| `404`  | Resource not found (or not in your workspace)      | `not_found`                  |
| `409`  | Conflict — e.g. a guardrail rejection              | `risk_limit_exceeded`        |
| `422`  | Semantically invalid (e.g. price out of range)     | `invalid_argument`           |
| `429`  | Rate limited — back off and retry                  | `rate_limited`               |
| `5xx`  | Upstream/venue failure                             | `internal`, `upstream_error` |

<Note>
  A guardrail rejection is a **normal, expected** response, not a bug. It means
  Mithril protected you — the order never reached the venue. See
  [Guardrails](/guides/guardrails).
</Note>

## Handling errors

```python theme={null}
resp = s.post(f"{BASE}/v1/orders", headers=idem, json=body)
if not resp.ok:
    err = resp.json()["error"]
    if err["code"] == "risk_limit_exceeded":
        # tighten size or raise the limit — this is a guardrail doing its job
        ...
    else:
        raise RuntimeError(f"[{resp.status_code}] {err['message']} ({err['request_id']})")
```