Borrowing it
Nothing to install: this file belongs to drisplabs/browser-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/drisplabs/browser-mcp/main/CLAUDE.mdgit clone --depth 1 https://github.com/drisplabs/browser-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/drisplabs/browser-mcp/claude-md)<a href="https://agentmods.dev/instructions/drisplabs/browser-mcp/claude-md"><img src="https://agentmods.dev/badge/instructions/drisplabs/browser-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 | $0.01909 | $0.01909 |
| Opus 5 | $0.00955 | $0.00955 |
| Sonnet 5 | $0.00382 | $0.00382 |
| Haiku 4.5 | $0.00191 | $0.00191 |
Grade A, and why
browser-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 6d 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 — 213 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
Drisp Browser is an MCP (Model Context Protocol) server for AI-powered browser automation via Puppeteer and CDP (Chrome DevTools Protocol). It provides semantic page snapshots - compact, structured representations designed for LLM consumption with stable element IDs that survive DOM mutations.
25 Tools across 9 categories:
- Session: list_pages, close_page
- Navigation: navigate, go_back, go_forward, reload
- Observation: snapshot, find, get_element, screenshot
- Interaction: click, type, press, select, hover, scroll_to, scroll, drag, wheel
- Canvas: inspect_canvas
- Form Understanding: get_form, get_field
- Content: read_page
- Network: list_network_calls, search_network_calls
Build and Development Commands
# Build
npm run build # Compile TypeScript
npm run dev # Watch mode compilation
# Quality checks
npm run type-check # TypeScript type checking
npm run lint # ESLint
npm run lint:fix # ESLint with auto-fix
npm run format # Prettier format
npm run check # Run all checks (type-check + lint + format:check + test)
# Testing
npm test # Run all tests once
npm run test:watch # Watch mode for development
npm run test:coverage # Generate coverage report
npm run test:unit # Run only unit tests
npm run test:integration # Run only integration tests
# Run single test file
npx vitest run tests/unit/browser/session-manager.test.ts
# Run tests matching pattern
npx vitest run -t "should launch with default options"
# Debug/inspect
npm run mcp:inspect # MCP protocol inspector
Architecture
AI Agent
↓ MCP Protocol (stdio)
Tool Handlers (browser-tools.ts)
↓
┌─────────────────────────────────────┐
│ Core Systems │
│ ├─ SessionManager (lifecycle) │
│ ├─ StateManager (state + diff) │
│ ├─ SnapshotCompiler (extraction) │
│ └─ ElementRegistry (eid lookup) │
└─────────────────────────────────────┘
↓ Puppeteer + CDP
Chromium Browser
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.
- 6d ago First seen · 213 lines · 1,909 tokens per session scan A 28ecd18a5f67
browser-mcp CLAUDE.md is an instructions file published in the GitHub repository drisplabs/browser-mcp (15 stars, last pushed 20d ago), licensed MIT. It adds 1,909 tokens to every session, about $0.0095 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 2026-08-30.
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