Fix n8n MCP AI Agent OAuth2 Silent Tool Failure
The AI Agent says it used no tools and the run shows success - the real cause is an OAuth2 token n8n never refreshes in an MCP context.
Topic
No-Code
A collection of 54 issues
Fix the Zapier Tables Cannot Create ULID 400 Error
The 400 'Cannot create ULID from string' error is a field-mapping mistake, not a broken table - here is how to feed Zapier Tables a valid Record ID.
Fix n8n's MCP Webhook Heap Leak in Queue Mode
Why memory climbs to an OOM crash on n8n workers running an MCP Trigger in queue mode, and the exact version that fixes the SessionManager leak.
How to fix Make's Retry error handler (formerly Break) not triggering
Make's Retry error handler (formerly Break) silently skips HTTP module failures until you flip one toggle on the HTTP module itself.
Self-hosting n8n with Docker Compose in 2026: complete walkthrough
Run n8n on your own server with Docker Compose and Traefik: compose.yaml, .env, WEBHOOK_URL, and N8N_PROXY_HOPS=1 — the setting most guides skip.
How to throw a custom error in an n8n Code node inside a loop
Two patterns for collecting per-item errors in n8n loops without halting the workflow - including the silent colon-truncation bug in Continue mode.
Automate social media posting with n8n: full workflow walkthrough
Build one n8n workflow that reads a Google Sheets queue and posts to all four major platforms -- including the Instagram two-step container trick and Meta token renewal.
n8n Code node: how to install and use external npm packages
Allowlist and install external npm packages for the n8n Code node - including the n8n 2.x task-runner gotcha most guides skip.
How to fix n8n nested loops: the inner loop retains completed state bug
The inner Loop Over Items node skips processing after the first outer iteration because it retains its completed state. Here are the three fixes, including the Done-branch chain pattern that avoids the bug entirely.
Send automated emails with n8n: SMTP, Gmail, and templates
Set up Gmail SMTP credentials, build HTML templates with dynamic data, and wire the Send Email node into any n8n workflow.