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

# Error handling

> Error codes returned by the Mint Manager SDK.

Every failure the SDK raises is a `MintManagerError` carrying a stable `code`. Branch on `code`; the `message` is written for a human reading a log and may change between releases.

```typescript theme={null}
import { MintManagerError } from '@thenamespace/mint-manager';

try {
  const check = await mintClient.checkName('alice.example.eth', {
    minterAddress: '0x1D84ad46F1ec91b4Bb3208F645aD2fA7aBEc19f8',
  });
} catch (error) {
  if (!(error instanceof MintManagerError)) throw error;

  switch (error.code) {
    case 'RPC_ERROR':
      // Infrastructure, not the name. Offer a retry.
      break;
    case 'PRICE_EXCEEDS_MAX':
      // The price moved past your cap. Re-quote and confirm with the user.
      break;
    default:
      console.error(error.code, error.message, error.details);
  }
}
```

Each error also carries `details` with the offending values, and often `docsUrl` and `cause`.

### Error codes

| Code                   | Cause                                                                               | How to handle it                                                                                                        |
| ---------------------- | ----------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------- |
| `INVALID_NAME`         | A full name failed ENSIP-15 normalization, or was empty                             | Reject the input at the form and show the reason                                                                        |
| `INVALID_LABEL`        | A label was empty, contained `.`, was an encoded labelhash, or failed normalization | Usually a full name passed where a label was expected                                                                   |
| `INVALID_ADDRESS`      | A value that must be a 20-byte EVM address was not one                              | Resolve ENS names to addresses first; checksums must be correct                                                         |
| `UNSUPPORTED_CHAIN`    | The chain has no Namespace deployment in this environment                           | Check `isTestnet`. Mainnet and testnet chains are separate sets                                                         |
| `UNSUPPORTED_LISTING`  | The listing is neither `L1` nor `L2`                                                | Offchain names mint with [Offchain Manager](/developer-guide/sdks/offchain-manager) instead                             |
| `NAME_NOT_AVAILABLE`   | A check result that was not `available` reached `prepareMint`                       | Handle `taken` and `blocked` first                                                                                      |
| `LISTING_NOT_FOUND`    | No listing exists for the parent name on the selected network                       | Activate the name in the [Namespace App](/user-guide/app#activate-your-ens-name), or check `isTestnet` and the spelling |
| `RPC_ERROR`            | A contract read or JSON-RPC call failed                                             | Retryable. Supply your own `customRpcUrls`                                                                              |
| `API_ERROR`            | The Namespace API returned a non-2xx response                                       | A 404 usually means the name is not listed on this network; retry 5xx with backoff                                      |
| `MINT_PARAMS_MISMATCH` | The API signed a different label, parent, or owner than requested                   | Normalize inputs first, then request parameters with the normalized values                                              |
| `PRICE_EXCEEDS_MAX`    | The quoted total exceeded your `maxValue`                                           | Nothing was submitted. Re-quote, then raise the cap or show the new price                                               |
| `SIGNATURE_EXPIRED`    | The mint authorization is past its expiry                                           | Call `prepareMint` again and submit promptly                                                                            |
| `CONFIG_ERROR`         | `createMintClient` received unusable options, such as a plain `http` URI override   | Fix the options and construct the client again                                                                          |

## RPC\_ERROR is not an answer about the name

A failed registry lookup means the name's status is unknown, not unavailable. Showing "name taken" on the strength of an RPC failure tells a user a free name is gone, and they leave.

```typescript theme={null}
try {
  const check = await mintClient.checkName(name, { minterAddress });
} catch (error) {
  if (error instanceof MintManagerError && error.code === 'RPC_ERROR') {
    showRetryableError('Could not reach the registry. Try again.');
  }
}
```

The usual cause is rate limiting on the shared public endpoint. Pass your own endpoints keyed by numeric chain ID. The error reports which chain failed in `details.chainId`.

```typescript theme={null}
const mintClient = createMintClient({
  customRpcUrls: {
    1: process.env.MAINNET_RPC_URL,
    8453: process.env.BASE_RPC_URL,
  },
});
```

## The signed quote is verified for you

Three codes cover the signed mint parameters the API returns. The SDK checks that the signature matches the mint you asked for before the transaction reaches a wallet. A mismatched or tampered response throws at this step.

* `MINT_PARAMS_MISMATCH`. The signed label, parent node, or owner disagrees with the request.
* `PRICE_EXCEEDS_MAX`. The total is above the ceiling you set. See [`maxValue`](/developer-guide/sdks/mint-manager/get-mint-transaction-parameters#cap-the-price-with-maxvalue).
* `SIGNATURE_EXPIRED`. The authorization aged out between quoting and submitting.