# adapter_error (/docs/reference/errors/adapter-error)



`EmailAdapterError` exposes:

* `adapter`
* optional HTTP `status`
* optional provider `requestId`
* `retryable`
* `delivery: "not_sent" | "unknown"`
* standard `cause`

`not_sent` means fallback may proceed. `unknown` means delivery cannot be ruled out and fallback stops by default.

```ts title="src/send.ts"
if (error instanceof EmailAdapterError && error.delivery === "unknown") {
  await reconcileProviderState(error.requestId);
}
```

A retryable flag does not override abort or unknown-delivery policy. It only participates in the configured retry decision for the current adapter.