@yocoolab/mcp-server
MCP (Model Context Protocol) server that exposes Yocoolab feedback threads and design selections as tools for Claude Code and other MCP-compatible clients.
With this installed, your AI coding assistant can:
- List and triage open design feedback threads on your repo
- Pull rich context for a thread (selection, screenshot, conversation, files touched)
- Reply to designers and mark threads as addressed
- Open PRs that close out feedback threads
- Inspect element context and selection history from the Yocoolab Chrome extension
- Read companion chat messages, AI conversations, and Pendo product analytics
Install
One command:
npx -y @yocoolab/mcp-server@3 setup
The setup wizard auto-detects your installed AI agents (Claude Code, Cursor, Cline, Roo Code, Windsurf) and writes the correct MCP config for each. Restart your agent and the yocoolab server appears with all tools available.
init is kept as an alias for setup for backwards compatibility with v1.0.x install instructions.
If you'd rather configure manually, the equivalent ~/.mcp.json looks like:
{
"mcpServers": {
"yocoolab": {
"command": "npx",
"args": ["-y", "@yocoolab/mcp-server@3"],
"env": {
"YOCOOLAB_API_URL": "https://app.yocoolab.com",
"YOCOOLAB_TOKEN": "<your-yocoolab-jwt>",
"GITHUB_TOKEN": "<your-github-pat>",
"YOCOOLAB_BRIDGE_PORT": "9800",
"YOCOOLAB_BRIDGE_WORKSPACE": "/absolute/path/to/your/workspace"
}
}
}
}
The @3 version pin keeps you on the v3 major line — you'll receive bug fixes and new features automatically, but a future v4 with breaking changes won't break your setup. v3.0.0 removed the activity monitor and no longer writes Claude Code hooks into ~/.claude/settings.json; see CHANGELOG.md if you are upgrading from v2.
Requirements
- Node.js 20 or newer. We test on Node 20 and 22 in CI. We support whichever Node.js versions are currently in Active LTS or Maintenance LTS status, and drop versions within 30 days of their EOL. Node 18 was dropped in v2.0.0 (EOL April 2025).
- A Yocoolab account and JWT token — get yours from the Yocoolab Chrome extension settings, or via your account at app.yocoolab.com.
- A GitHub personal access token with
repo scope, if you want to use the PR-creation tools (create_pr_for_thread). The token is auto-detected if you have the GitHub CLI installed and authenticated (gh auth login). No GITHUB_TOKEN env var needed in that case. Otherwise, create one at github.com/settings/tokens/new?scopes=repo.
Configuration
| Env var | Required | Default | Description |
|---|
YOCOOLAB_TOKEN | no | — | Your Yocoolab JWT (from the Chrome extension). When unset, thread feedback tools are disabled but bridge / companion / selection tools still work. |
YOCOOLAB_API_URL | no | https://app.yocoolab.com | Yocoolab API base URL |
GITHUB_TOKEN | only for PR tools | — | GitHub PAT with repo scope. Auto-detected — if gh CLI is installed and authenticated (gh auth token), no env var is needed. Placeholder values like <your GitHub PAT> are detected and safely ignored. |
YOCOOLAB_BRIDGE_PORT | no | 9800 | Local port for the HTTP bridge to the Chrome extension |
YOCOOLAB_BRIDGE_WORKSPACE | no | process.cwd() | Absolute path to your project workspace, used to resolve file references in selections |
YOCOOLAB_AGENT_NAME | no | Claude Code | Display name shown in the Chrome extension's agent picker |
YOCOOLAB_PROJECT_PR_LINKS | no | 1 | Set to 0 to restore the pre-2.5 behaviour: mark_thread_addressed without PR/preview link fields, GitHub-only PR guidance in the prompt |
YOCOOLAB_AGENT_TYPE | no | claude-code | Agent type identifier (claude-code, roo, cline, cursor, windsurf, or custom) |
CLI
yocoolab-mcp Run the MCP server (used by your agent via .mcp.json)
yocoolab-mcp setup Interactive setup — auto-detects agents and writes their configs
yocoolab-mcp init Alias for `setup` (backwards compatible with v1.0.x)
yocoolab-mcp --help Show this help
The mcp-server command is a synonym for yocoolab-mcp. Either works.
The server exposes tools across several categories:
- Threads —
list_open_threads, get_thread_context, add_thread_message, mark_thread_addressed, create_pr_for_thread
- On a link-only project (no GitHub App connection) open the PR with your own git/
gh, then call mark_thread_addressed with pr_url (and pr_branch, preview_url when you have them). The PR fields land on the thread and the preview link goes into the review message; get_thread_context prints the project's repo links so you know which repository it points at. create_pr_for_thread remains for GitHub-connected owner/name workspaces.
- Selection / Bridge —
get_latest_selection, get_selection_history, get_element_context, find_source_for_selection, ai_analyze_page
- Companion —
get_companion_messages, reply_to_companion
- AI —
get_ai_conversations
- Deployment —
get_deployment_preview
- Pendo (optional) —
pendo_list_guides, pendo_page_analytics, pendo_feature_usage, pendo_track_event
For full tool descriptions and parameters, your MCP client will list them after the server starts.
Troubleshooting
yocoolab-mcp: command not found — make sure you're on v1.0.1 or newer. Run npx -y @yocoolab/mcp-server@latest setup to get the current release.
[yocoolab] Warning: YOCOOLAB_TOKEN not set — thread feedback tools are disabled without a token, but bridge / companion / selection tools still work. To enable everything, run yocoolab-mcp setup to (re)generate the config with your JWT.
Tools don't appear in your agent after install — restart your agent completely (quit & reopen). MCP servers load at startup.
Port 9800 is already in use — another instance of the MCP server is running, or another app has the port. Set YOCOOLAB_BRIDGE_PORT to a different value (e.g. 9801) in your .mcp.json.
Verbose diagnostic logs — set DEBUG=yocoolab:* in your env block. All diagnostic output goes to stderr (so it doesn't interfere with the MCP stdio protocol on stdout).
PR creation says "GitHub token not configured" — the create_pr_for_thread tool needs a GitHub token. Two ways to fix:
- Auto-detect (easiest): install the GitHub CLI and run
gh auth login. The server picks up the token automatically.
- Manual: create a personal access token with
repo scope and add GITHUB_TOKEN: "ghp_..." to your MCP config's env block.
If your config has a placeholder value like <your GitHub PAT>, the server detects it and shows a helpful message instead of crashing with a 401.
Support
Development
git clone https://github.com/Yocoolab/mcp-server.git
cd mcp-server
npm install
npm run build
npm test
npm run dev
See CONTRIBUTING.md for the full contributor workflow.
Security & supply chain
- Released with npm provenance — every published version is cryptographically signed by GitHub Actions OIDC, traceable back to the exact commit and workflow run.
- Each release ships with a CycloneDX SBOM attached to the GitHub Release.
- We run
npm audit signatures and CodeQL static analysis in CI on every PR.
- See SECURITY.md for vulnerability reporting.
License
Apache 2.0 — © 2026 Yocoolab