Diagnose and fix Claude in Chrome MCP extension connectivity issues. Use when mcp__claude-in-chrome__* tools fail, return "Browser extension is not connected", or behave erratically.
Installs just this skill. Get the whole plugin for auto-invocation.
⚡ How it fires
How this skill gets triggered: by you, by Claude, or both.
Fires itselfClaude auto-loads it when your prompt matches the work.
You can call itInvoke it directly when you want it.
Slash command/chrome-mcp-troubleshooting
👁️ Context preview
The summary Claude sees to decide when to auto-load this skill.
Diagnose and fix Claude in Chrome MCP extension connectivity issues. Use when mcp__claude-in-chrome__* tools fail, return "Browser extension is not connected", or behave erratically.
📊 Stats
Stars6,229
Forks540
LanguagePython
LicenseCC-BY-SA-4.0
📦 Ships with trailofbits-skills
</> SKILL.md
chrome-mcp-troubleshooting.SKILL.md
---name: chrome-mcp-troubleshooting
description: Diagnose and fix Claude in Chrome MCP extension connectivity issues. Use when mcp__claude-in-chrome__* tools fail, return "Browser extension is not connected", or behave erratically.
---# Claude in Chrome MCP Troubleshooting
Use this skill when Claude in Chrome MCP tools fail to connect or work unreliably.
## When to Use
- `mcp__claude-in-chrome__*` tools fail with "Browser extension is not connected"
- Browser automation works erratically or times out
- After updating Claude Code or Claude.app
- When switching between Claude Code CLI and Claude.app (Cowork)
- Native host process is running but MCP tools still fail
## When NOT to Use
- **Linux or Windows users** - This skill covers macOS-specific paths and tools (`~/Library/Application Support/`, `osascript`)
- General Chrome automation issues unrelated to the Claude extension
- Claude.app desktop issues (not browser-related)
- Network connectivity problems
- Chrome extension installation issues (use Chrome Web Store support)
## The Claude.app vs Claude Code Conflict (Primary Issue)
**Background:** When Claude.app added Cowork support (browser automation from the desktop app), it introduced a competing native messaging host that conflicts with Claude Code CLI.
# Claude Code: ~/.local/share/claude/versions/X.X.X --chrome-native-host
# 2. Where is the socket?
# For Claude Code (single file in TMPDIR):
ls -la "$(getconf DARWIN_USER_TEMP_DIR)/claude-mcp-browser-bridge-$USER" 2>&1
# For Claude.app (directory with PID files):
ls -la /tmp/claude-mcp-browser-bridge-$USER/ 2>&1
# 3. What's the native host connected to?
lsof -U 2>&1 | grep claude-mcp-browser-bridge
# 4. Which configs are active?
ls ~/Library/Application\ Support/Google/Chrome/NativeMessagingHosts/com.anthropic*.json
```
## Critical Insight
**MCP connects at startup.** If the browser bridge wasn't ready when Claude Code started, the connection will fail for the entire session. The fix is usually: ensure Chrome + extension are running with correct config, THEN restart Claude Code.
1. **Primary issue:** Claude.app (Cowork) and Claude Code use different native hosts with incompatible socket formats
2. **Fix:** Disable the native messaging config for whichever one you're NOT using
3. **After any fix:** Must restart Chrome AND Claude Code (MCP connects at startup)
4. **One profile:** Only have Claude extension in one Chrome profile
5. **One session:** Only run one Claude Code instance
---
*Original skill by [@jeffzwang](https://github.com/jeffzwang) from [@ExaAILabs](https://github.com/ExaAILabs). Enhanced and updated for current versions of Claude Desktop and Claude Code.*
