twentyhq/twenty · error · Error

Failed to describe cron expression: ${errorMessage}

Error message

Failed to describe cron expression: ${errorMessage}

What it means

Top-level catch-all wrapper in describeCronExpression: any error thrown inside the try block (most commonly from parseCronExpression) is re-thrown with the prefix 'Failed to describe cron expression: ' plus the inner error message. This is the error users see for malformed cron input.

Source

Thrown at packages/twenty-front/src/modules/workflow/workflow-trigger/utils/cron-to-human/describeCronExpression.ts:114

    }
    const monthsDesc = getMonthsDescription(
      parts.month,
      mergedOptions,
      localeCatalog,
    );
    if (isDefined(monthsDesc) && monthsDesc !== '') {
      descriptions.push(monthsDesc);
    }

    if (descriptions.length === 0) {
      return t`every minute`;
    }
    // Simple joining - just use spaces, no commas for cleaner descriptions
    return descriptions.join(' ');
  } catch (error) {
    const errorMessage =
      error instanceof Error ? error.message : 'Unknown error';
    throw new Error(`Failed to describe cron expression: ${errorMessage}`);
  }
};

View on GitHub (pinned to 1f5dd2bbd2)

Solutions

1. Read the suffixed inner message to identify which validation failed (field count vs cron-parser range error).
2. Correct the cron expression to valid 5-field syntax with in-range values.
3. If surfacing to users, strip the 'Failed to describe cron expression: ' prefix and show only the inner reason.

Example fix

// before: cron '99 99 * * *'  -> 'Failed to describe cron expression: Invalid cron expression: ...'
// after:  cron '0 9 * * *'   -> 'at 09:00'

const tryDescribeCron = (expr: string): string => {
  try { return describeCronExpression(expr); }
  catch (e) { return ''; }
};

const isValidCron = (expr: string): boolean => {
  try { parseCronExpression(expr); return true; } catch { return false; }
};

try {
  const human = describeCronExpression(expr);
} catch (e) {
  // strip the wrapper prefix to show only the inner reason
  const inner = (e as Error).message.replace(/^Failed to describe cron expression: /, '');
  setScheduleError(inner);
}

When it happens

Trigger: parseCronExpression throws (invalid field count, cron-parser rejects out-of-range values like minute 99). A descriptor helper throws on unsupported syntax. Any non-Error throw produces 'Unknown error'.

Common situations: User types an invalid cron expression in the workflow schedule editor (e.g., '99 99 * * *', '*/5 / / * *', too many fields). Out-of-range or non-numeric field values.

Related errors

• Cron expression is required
• Cron expression is required
• Invalid cron expression. Expected 4-6 fields, got ${parts.le
• Malformed workflow version: missing steps information; be su
• Invalid cron expression: ${errorMessage}

AI-assisted analysis of twentyhq/twenty@1f5dd2bbd2 (2026-08-12). Data as JSON: /api/errors/e0ddee75b98ae60a. Report an issue: GitHub.