n8n MCP server: build, lint, and debug workflows from your AI agent Nine tools that generate correct n8n JSON, lint for the failure modes that matter, and diagnose silent data loss. Install snippets for Cursor, Claude Code, and six more hosts.
n8n Code node: Run Once for All Items vs Each Item Run Once for All Items uses $input.all() and returns an array; Run Once for Each Item uses $json and returns { json: ... }. Three traps to watch.
n8n webhook returns 404: the most common causes and fixes Production webhook 404 in n8n almost always traces to one of four causes. Here's how to identify which and fix it in under five minutes.
How to fix the n8n "ECONNREFUSED" error in HTTP Request nodes Inside the n8n container, localhost is the container - not your machine. The one-line fix, plus the IPv6 gotcha most guides miss.
Self-hosting n8n on a $5 DigitalOcean VPS: complete 2026 setup walkthrough A 1 GB Ubuntu droplet, Docker Compose with n8n + Caddy, and the WEBHOOK_URL setting most tutorials skip - run in under 15 minutes.