n8n Workflow Watchdog: Monitor Failures via API & Alert Email/Slack

Never miss a failing n8n workflow again — receive automatic email (and optional Slack) alerts

n8n Workflow Watchdog runs every hour to monitor your selected n8n workflows via the n8n API, detects missing executions and recent errors/crashes, and then notifies you by email and optionally Slack with a timestamped issue summary.

What this workflow does

• Runs hourly: Executes on a schedule to keep monitoring continuous.
• Loads watchdog configuration: Reads which workflow IDs to watch, the silent window, execution limits, and alert recipients/settings.
• Queries n8n API executions: Splits the configured workflow ID list and requests the most recent executions for each workflow.
• Flags issues: Detects workflows with no runs within the configured time window, recent error/crashed runs, and (optionally) successful runs whose last executed node output zero items.
• Sends alerts: When problems are found, it sends an alert email with a timestamped summary and issue count.
• Posts to Slack (optional): If enabled, it posts the same issue summary to your configured Slack channel.

Use cases

• Catch stalled automations when a critical workflow stops executing (silentHours monitoring).
• Get immediate visibility into workflows that crash or fail with errors.
• Detect “success without results” scenarios when a workflow completes but outputs zero items.
• Operate SaaS and internal automation with confidence using email/Slack notifications for reliability.

Technical details

• Integrations: Uses the n8n API for execution/list (and execution read if required) to fetch recent workflow executions.
• Nodes / tools: Built with if, set, code, email send, and slack (when Slack alerts are enabled).
• Setup requirements: Add an n8n API key, configure SMTP credentials for email, and optionally add a Slack OAuth credential plus target channel ID.

Set it up once, then let the n8n Workflow Watchdog continuously protect your automations with actionable alerts.