Borrowing it
Nothing to install: this file belongs to docentovich/chrometools-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/docentovich/chrometools-mcp/main/CLAUDE.mdgit clone --depth 1 https://github.com/docentovich/chrometools-mcpWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/instructions/docentovich/chrometools-mcp/claude-md)<a href="https://agentmods.dev/instructions/docentovich/chrometools-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/docentovich/chrometools-mcp/claude-md.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.02168 | $0.02168 |
| Opus 5 | $0.01084 | $0.01084 |
| Sonnet 5 | $0.00434 | $0.00434 |
| Haiku 4.5 | $0.00217 | $0.00217 |
Grade A, and why
chrometools-mcp CLAUDE.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 7d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 311 lines — stays where its author put it; the contents beside it link to each section on GitHub.
CLAUDE.md
This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
Project Overview
chrometools-mcp - MCP (Model Context Protocol) server for Chrome automation using Puppeteer.
Cross-platform MCP server (Windows/WSL, Linux, macOS) that provides Chrome browser automation capabilities.
Active Specs
| Spec | Status | Progress |
|---|---|---|
| SEGM-537 QA Unblockers | NEEDS APPROVAL | progress |
| Novofon Blockers (iframe/session/P1) | CODE COMPLETE — needs live e2e | progress |
Key Architecture Concept
Persistent Browser Sessions: Browser tabs remain open after command execution, allowing users to:
- Prepare pages manually between AI iterations
- Continue work from previous state
- Interact with pages between MCP server calls
This enables iterative workflows where the user and AI collaborate within the same browser session.
Installation & Usage
Users install and run via npx (single command, no setup):
npx chrometools-mcp
This design makes installation automatic and simple for end users.
Development Commands
# Install dependencies
npm install
# Run tests
npm test
# Build
npm run build
# Development/testing
npm start
# or
node index.js
Technology Stack
- Puppeteer: Chrome automation library
- MCP SDK:
@modelcontextprotocol/sdkfor server implementation - Transport: stdio (standard for MCP servers)
Core Workflow
- User runs
npx chrometools-mcp(or adds to MCP config) - MCP server launches Puppeteer with
headless: false - AI sends commands via MCP tools → Server executes in Chrome
- Browser tabs stay open after execution
- User can manually interact with pages
- Next AI request continues from current browser state
Implementation Guidelines
Puppeteer Configuration
// Browser should persist between commands
const browser = await puppeteer.launch({
headless: false, // User needs to see and interact
// Keep browser alive between MCP calls
});
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 7d ago First seen · 311 lines · 2,168 tokens per session scan A bc48000296e5
chrometools-mcp CLAUDE.md is an instructions file published in the GitHub repository docentovich/chrometools-mcp (9 stars, last pushed 2mo ago), licensed ISC. It adds 2,168 tokens to every session, about $0.0108 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other instructions, from other repositories
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.