browser-use-rules

browser-use-rules is a cursor rule for Cursor from dsouza-anush/browser-use-heroku. It costs 662 tokens per session, scanned A, original, MIT.

A set of development rules for Browser-Use, an AI agent that operates websites through Chromium and Playwright. The rules cover file documentation, dependency installation, model names, and typed data structures.

In plain words
What is it for?
Use it when adding features, fixing bugs, or creating files in the Browser-Use project.
Why use it?
It keeps changes consistent and makes the code easier for both developers and AI agents to understand. It also reduces mistakes caused by unclear files, unapproved dependency tools, or incorrect model names.

Cursor rule for Cursor

Written for Cursor: installed under .cursor/.

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 rules/dsouza-anush/browser-use-heroku/browser-use-rules
Clone the repo
git clone --depth 1 https://github.com/dsouza-anush/browser-use-heroku

Made for: Cursor.

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 browser-use-rules

README.md
[![agentmods](https://agentmods.dev/badge/rules/dsouza-anush/browser-use-heroku/browser-use-rules.svg)](https://agentmods.dev/rules/dsouza-anush/browser-use-heroku/browser-use-rules)
Your own site
<a href="https://agentmods.dev/rules/dsouza-anush/browser-use-heroku/browser-use-rules"><img src="https://agentmods.dev/badge/rules/dsouza-anush/browser-use-heroku/browser-use-rules.svg" alt="Measured on agentmods" height="20"></a>
Per session 662 This file is loaded in full into every session.
When invoked 662 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 5.1 $0.00662 $0.00662
Opus 5 $0.00331 $0.00331
Sonnet 5 $0.00132 $0.00132
Haiku 4.5 $0.00066 $0.00066

Measured 5d ago against content hash 2f754f2606a7, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

browser-use-rules 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.

.cursor/rules/browser-use-rules.mdc · 91 lines

How it starts

The opening of the file, as written. The whole thing — 91 lines — stays where its author put it; the contents beside it link to each section on GitHub.

🧠 General Guidelines for Contributing to browser-use

Browser-Use is an AI agent that autonomously interacts with the web. It takes a user-defined task, navigates web pages using Chromium via Playwright, processes HTML, and repeatedly queries a language model (like gpt-4o) to decide the next action—until the task is completed.

🗂️ File Documentation

When you create a new file:

  • For humans: At the top of the file, include a docstring in natural language explaining:

    • What this file does.
    • How it fits into the browser-use system.
    • If it introduces a new abstraction or replaces an old one.
  • For LLMs/AI: Include structured metadata using standardized comments such as:

    # @file purpose: Defines <purpose>
    

🧰 Development Rules

  • Always use uv instead of pip For deterministic and fast dependency installs.
uv venv --python 3.11
source .venv/bin/activate
uv sync
  • Use real model names Do not replace gpt-4o with gpt-4. The model gpt-4o is a distinct release and supported.

  • Type-safe coding Use Pydantic v2 models for all internal action schemas, task inputs/outputs, and controller I/O. This ensures robust validation and LLM-call integrity.

  • Pre-commit formatting ALWAYS make sure to run pre-commit before making PRs.


⚙️ Adding New Actions

To add a new action that your browser agent can execute:

from playwright.async_api import Page
from browser_use.core.controller import Controller, ActionResult

controller = Controller()

@controller.registry.action("Search the web for a specific query")
async def search_web(query: str, page: Page):
    # Implement your logic here, e.g., query a search engine and return results
    result = ...
    return ActionResult(extracted_content=result, include_in_memory=True)

Notes:

  • Use descriptive names and docstrings for each action.
  • Prefer returning ActionResult with structured content to help the agent reason better.

Read the full file on GitHub · 91 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 · 91 lines · 662 tokens per session scan A 2f754f2606a7

Subscribe to this mod's changes

browser-use-rules is a cursor rule published in the GitHub repository dsouza-anush/browser-use-heroku (1 stars, last pushed 1y ago), licensed MIT. It adds 662 tokens to every session, about $0.0033 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.