n8n Error Handler: Claude diagnosis + Gmail alerts

Stop error alerts from turning into alert fatigue—while still getting instant, plain-English diagnoses

This n8n Error Handler workflow catches failed executions across your monitored workflows, suppresses repeat notifications, sends detailed failure context to Claude via the Anthropic Messages API for a likely cause and fix steps, and then emails a formatted diagnostic alert through Gmail (including a link to the failed execution when available).

What this workflow does

• Global failure trigger: Runs automatically whenever an execution fails in any workflow configured to use it as the workflow’s n8n Error Workflow.
• Extracts failure details: Captures the workflow name/ID, the failing node, the error message, and a trimmed stack trace for concise reporting.
• Suppresses duplicates: Uses workflow static data to detect repeated failures and prevents sending repeat alerts within a configurable cooldown window.
• Asks Claude for diagnosis: For new (non-suppressed) failures, builds a structured prompt and JSON schema and calls the Anthropic Messages API to return severity, whether the issue is transient, a summary, a likely cause, and up to four fix steps.
• Email-ready formatting: Creates a readable plain-text alert email, falling back to raw error details if the AI response cannot be parsed.
• Sends Gmail alert with context: Emails the recipient configured in the workflow settings, including repeat counts and a link to the failed execution when available.

Use cases

• SaaS operators who need dependable error visibility across multiple n8n workflows without spamming their inbox.
• Automation engineers debugging production incidents with actionable, Claude-generated fix steps.
• Teams that want consistent error reports with execution links for rapid root-cause investigation.

Technical details

• n8n logic & control: if, set, code
• Notifications: gmail (email alerts); includes slack and a sticky note as part of the workflow components.
• AI diagnosis: Calls the Anthropic Messages API using ANTRHOPIC_API_KEY.

Setup: Configure this workflow as the “Error Workflow” in each monitored workflow’s settings, then set the recipient email (e.g., notifyTo), cooldown duration (e.g., cooldownMinutes), and your Anthropic API key.