n8n-expression-syntax

To fix n8n expression syntax errors, ensure you correctly wrap variables with {{}} and reference $json or $node accurately. Proper syntax prevents runtime errors and ensures correct data extraction from your workflow nodes.

The correct way to reference node data in n8n expressions is using the $node syntax wrapped in {{}}. This ensures safe node references and accurate data extraction, preventing data leakage and broken workflow logic.

Your n8n expression returns undefined because webhook payload data is nested under the .body property. You must access it via $json.body instead of referencing the root $json object directly to extract the correct values.

Common n8n expression mistakes include forgetting the {{}} wrapper, incorrectly referencing $json for webhook body data, and unsafe node references. Following strict syntax rules and debugging patterns prevents these runtime errors.