browsercontrol CLAUDE.md

browsercontrol CLAUDE.md is an instructions file for coding agents from adityasasidhar/browsercontrol. It costs 1,432 tokens per session, scanned A, original, MIT.

Repository instructions for BrowserControl, an MCP server that lets AI agents control browsers through Playwright and annotated screenshots. Playwright is a browser-automation tool, and the annotations number clickable elements for the agent.

In plain words
What is it for?
Use them to set up the project, run its tests and code checks, and automate browser actions by referring to numbered screenshot elements.
Why use it?
They explain how to install, test, lint, format, and operate the browser-control project without relying on unfamiliar selectors.

Instructions file

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add instructions/adityasasidhar/browsercontrol/claude-md
Clone the repo
git clone --depth 1 https://github.com/adityasasidhar/browsercontrol

Wrote 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.

agentmods badge for browsercontrol CLAUDE.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/adityasasidhar/browsercontrol/claude-md.svg)](https://agentmods.dev/instructions/adityasasidhar/browsercontrol/claude-md)
Your own site
<a href="https://agentmods.dev/instructions/adityasasidhar/browsercontrol/claude-md"><img src="https://agentmods.dev/badge/instructions/adityasasidhar/browsercontrol/claude-md.svg" alt="Measured on agentmods" height="20"></a>
Per session 1,432 This file is loaded in full into every session.
When invoked 1,432 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.01432 $0.01432
Opus 5 $0.00716 $0.00716
Sonnet 5 $0.00286 $0.00286
Haiku 4.5 $0.00143 $0.00143

Measured 5d ago against content hash 7e08b10f81c1, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

browsercontrol 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 5d 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.

CLAUDE.md · 116 lines

How it starts

The opening of the file, as written. The whole thing — 116 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.

Overview

BrowserControl is an MCP (Model Context Protocol) server that gives AI agents vision-first browser automation via Playwright. Its defining idea is Set of Marks (SoM): every action returns an annotated screenshot where interactive elements are overlaid with numbered red boxes, so the agent acts by referring to an element's number (click(7)) instead of CSS selectors or XPath.

Commands

This project uses uv for all dependency and task management.

uv sync                                    # Install deps (use --all-extras in CI to include dev group)
uv run playwright install chromium         # One-time: install the browser engine

uv run pytest                              # Run all tests
uv run pytest tests/test_navigation.py     # Run a single test file
uv run pytest tests/test_navigation.py::TestScroll::test_scroll_down_medium   # Single test
uv run pytest --cov=browsercontrol         # With coverage

uv run ruff check .                        # Lint
uv run ruff check . --fix                  # Lint + autofix
uv run ruff format .                       # Format (line length 100, double quotes)
uv run mypy browsercontrol/                # Type-check (strict mode)
uv run bandit -c pyproject.toml -r . --exclude ./tests,./.venv   # Security scan
uv run pre-commit run --all-files          # Run every hook (mirrors the CI lint job)

uv run fastmcp dev browsercontrol/server.py   # Run the server in dev mode with inspector
browsercontrol                                # Run the installed server (also: python -m browsercontrol)

CI (.github/workflows/ci.yml) gates on the lint job first, then runs tests on Linux/Windows/macOS plus bandit and mypy. Run ruff check, ruff format, and pytest locally before pushing.

Architecture

The flow is: agent calls an MCP tool → tool drives the Playwright page → a fresh annotated screenshot + element map is captured → both are returned to the agent.

Read the full file on GitHub · 116 lines

Changes

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.

  1. 5d ago First seen · 116 lines · 1,432 tokens per session scan A 7e08b10f81c1

Subscribe to this mod's changes

browsercontrol CLAUDE.md is an instructions file published in the GitHub repository adityasasidhar/browsercontrol (11 stars, last pushed 1mo ago), licensed MIT. It adds 1,432 tokens to every session, about $0.0072 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.