Errors

Treat error codes as the stable contract. Human-readable messages can add context and may change; the code identifies the class of failure.

TypeScript

try {
  const document = parseDocument(value);
} catch (error) {
  if (isKeyHoldError(error) && error.code === 'invalid_document') {
    // Ask for a fresh document.
  }
}

Go

document, err := keyhold.Parse(data)
if err != nil {
    switch keyhold.ErrorCodeOf(err) {
    case keyhold.ErrInvalidDocument:
        // Ask for a fresh document.
    }
}

The stable categories are invalid_json, unsupported_format, unsupported_version, invalid_document, unsupported_algorithm, invalid_parameter, invalid_private_key, and unlock_failed.