Is there an official comprehensive list of Metamask RPC Error codes?

Question

Metamask errors are handled using a JSON object with two fields.

1. Error Code (code)
2. Error Message (message)

Example if a user denies to sign a transaction:

{code: 4001, message: "MetaMask Tx Signature: User denied transaction signature."}

There does not seem to be a comprehensive list of possible error codes on the official Metamask docs.

I would like a comprehensive list, so I can implement it into my application and handle any possible error that metamask can detect.

Does a comprehensive list of all possible Metamask error codes exist?

Answer 1

Yes there is an official list. And here is an example implementation in Javascript JSON format:

const METAMASK_POSSIBLE_ERRORS = 
{
    '-32700': 
    {
        standard: 'JSON RPC 2.0',
        message: 'Invalid JSON was received by the server. An error occurred on the server while parsing the JSON text.',
    },
    '-32600': 
    {
        standard: 'JSON RPC 2.0',
        message: 'The JSON sent is not a valid Request object.',
    },
    '-32601': 
    {
        standard: 'JSON RPC 2.0',
        message: 'The method does not exist / is not available.',
    },
    '-32602': 
    {
        standard: 'JSON RPC 2.0',
        message: 'Invalid method parameter(s).',
    },
    '-32603': 
    {
        standard: 'JSON RPC 2.0',
        message: 'Internal JSON-RPC error.',
    },
    '-32000': 
    {
        standard: 'EIP-1474',
        message: 'Invalid input.',
    },
    '-32001': 
    {
        standard: 'EIP-1474',
        message: 'Resource not found.',
    },
    '-32002': 
    {
        standard: 'EIP-1474',
        message: 'Resource unavailable.',
    },
    '-32003': 
    {
        standard: 'EIP-1474',
        message: 'Transaction rejected.',
    },
    '-32004': 
    {
        standard: 'EIP-1474',
        message: 'Method not supported.',
    },
    '-32005': 
    {
        standard: 'EIP-1474',
        message: 'Request limit exceeded.',
    },
    '4001': 
    {
        standard: 'EIP-1193',
        message: 'User rejected the request.',
    },
    '4100': 
    {
        standard: 'EIP-1193',
        message: 'The requested account and/or method has not been authorized by the user.',
    },
    '4200': 
    {
        standard: 'EIP-1193',
        message: 'The requested method is not supported by this Ethereum provider.',
    },
    '4900': 
    {
        standard: 'EIP-1193',
        message: 'The provider is disconnected from all chains.',
    },
    '4901': 
    {
        standard: 'EIP-1193',
        message: 'The provider is disconnected from the specified chain.',
    },
}

Answer 2

All errors thrown or returned by the MetaMask provider follow this interface:

interface ProviderRpcError extends Error {
  message: string;
  code: number;
  data?: unknown;
}

The ethereum.request(args) method throws errors eagerly. You can often use the error code property to determine why the request failed. Common codes and their meaning include:

4001 : The request was rejected by the user

-32602: The parameters were invalid

-32603: Internal error

For the complete list of errors, please see EIP-1193 and EIP-1474