Topic

How To

Tactical how-to / step-by-step / troubleshooting

How to fix Claude Code MCP "spawn npx ENOENT" (and "spawn uv ENOENT") on Windows

On Windows, Node's spawn can't find .cmd shims or user-PATH tools like uv. Two fixes: the cmd /c wrapper and the full binary path - plus the plugin-cache gotcha that wipes the patch on update.

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.

Claude Code and Claude Desktop MCP config file: location and format (Windows/Mac/Linux)

Two tools, two config files. Claude Desktop reads claude_desktop_config.json; Claude Code reads ~/.claude.json -- not ~/.claude/settings.json, which many guides incorrectly recommend.

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.

Fix 'claude mcp add: unknown option --command' in the Claude Code CLI

No --command flag exists. Use -- to pass the command: claude mcp add myserver -- npx -y server. All options go before the server name.

Make scenario won't trigger: 7-step webhook diagnosis

Seven sequential checks to diagnose a Make scenario that won't run: covers webhooks, polling triggers, incomplete executions queue, scheduling, and timezone issues.

How to fix n8n OAuth callback URL returning 401

Three causes of the n8n OAuth callback 401 and the exact fixes: WEBHOOK_URL mismatch, stale credentials after a domain change, and X (Twitter) OAuth1/OAuth2 endpoint confusion.

Cursor: fix 'Waiting for extension host' hang

The 'Waiting for extension host' hang blocks Cursor's AI agent and extensions. Four fixes in order of effort: restart the host, disable extensions, wipe the state database, or update Cursor.

n8n Loop node only processes the first item: how to fix it

The Loop Over Items node only processes one batch when processing nodes aren't wired back to its input. Here's the exact fix, plus the Merge node pattern for conditional branches.