Installation
Install WebMCP Kit in Claude Code, Codex, or Cursor, and set up a browser that can run WebMCP tools.
Prerequisites
- Claude Code 2.1.220 or newer (
claude --version), Codex, or Cursor. - Your website’s repo, cloned locally, with a dev server you can run.
- Node.js and npm for the included verification browser driver.
- Bun for the Explorer and AgentLane connection.
Claude Code
Inside a Claude Code session:
/plugin marketplace add nekuda-ai/webmcp-kit
/plugin install webmcp-kit@nekuda
Or from your terminal — same result:
claude plugin marketplace add nekuda-ai/webmcp-kit
claude plugin install webmcp-kit@nekuda
Confirm it worked:
claude plugin details webmcp-kit@nekuda
Expect Skills (3): implement, verify, connect-existing-tools. The skills load as /webmcp-kit:implement, /webmcp-kit:verify, and /webmcp-kit:connect-existing-tools.
Codex
The plugin ships in the Agent Plugins open format, which Codex supports natively. In a Codex session:
- Run
/pluginsto open the plugin directory. - Add
nekuda-ai/webmcp-kitas a marketplace source. - Install
webmcp-kit.
Or run the same flow from your terminal:
codex plugin marketplace add nekuda-ai/webmcp-kit
codex plugin add webmcp-kit
Cursor
Run this from your project’s terminal:
npx skills add nekuda-ai/webmcp-kit --skill '*' --agent cursor
This installs implement, verify, and connect-existing-tools as Agent Skills. In Cursor, type / followed by a skill name to run one directly.
Browser setup
The kit includes a browser driver for verification. The skill starts a separate test browser with WebMCP enabled and closes it when finished. You do not need to configure a browser MCP server.
It uses a supported installed or cached browser. If none is available, it downloads Chrome for Testing on supported platforms. On Linux arm64, install a native Chrome or Chromium 150+ and set WEBMCP_BROWSER_PATH to its executable.
Testing in your own browser
For manual checks, use Chrome 150+ and enable WebMCP in chrome://flags. Older Chrome versions may expose navigator.modelContext instead; the SDK handles both. Visitors with unsupported browsers are unaffected because the SDK quietly does nothing there.
Quick check in devtools:
typeof document.modelContext // "object" when WebMCP is active
Updating
/plugin marketplace update