docs: add CONTRIBUTING guide and CI badge

CONTRIBUTING.md

@@ -0,0 +1,104 @@
+# Contributing to agent-browser
+
+Thanks for your interest in contributing to `agent-browser`! This guide covers how to set up the project locally, the expected coding style, and how to submit a pull request.
+
+## Development setup
+
+### Prerequisites
+
+- Node.js 20 or newer
+- pnpm
+- Rust toolchain (`rustup` recommended)
+- Chrome/Chromium or Chrome for Testing
+- Docker (optional, only needed for cross-platform build helpers)
+
+### Clone and install dependencies
+
+```bash
+git clone https://github.com/dextonai/agent-browser.git
+cd agent-browser
+pnpm install
+```
+
+### Build from source
+
+Sync package metadata and build the native CLI:
+
+```bash
+pnpm run version:sync
+pnpm run build:native
+```
+
+For platform-specific build helpers, use the existing package scripts:
+
+```bash
+pnpm run build:linux
+pnpm run build:macos
+pnpm run build:windows
+```
+
+### Install browser dependencies
+
+After building or installing the package, install Chrome for Testing:
+
+```bash
+agent-browser install
+```
+
+On Linux, you may also need system dependencies:
+
+```bash
+agent-browser install --with-deps
+```
+
+### Verify your changes
+
+Before opening a pull request, run the checks that apply to your change:
+
+```bash
+pnpm run version:sync
+pnpm run build:native
+```
+
+If you change Rust code, also run the relevant Cargo checks from the `cli` crate:
+
+```bash
+cargo fmt --manifest-path cli/Cargo.toml
+cargo test --manifest-path cli/Cargo.toml
+```
+
+## Coding style guidelines
+
+- Keep changes focused and small. One pull request should solve one problem.
+- Follow the existing project structure and naming conventions.
+- Prefer clear, explicit command names and error messages for CLI-facing behavior.
+- Keep documentation examples copy-pasteable and tested when practical.
+- Update README or docs when adding or changing user-facing behavior.
+- Do not commit generated build artifacts unless they are already part of the documented release process.
+- Avoid unrelated formatting changes in files you are not modifying.
+
+## Submitting a pull request
+
+1. Create a feature branch from the latest `main` branch.
+2. Make your changes and include tests or documentation updates when relevant.
+3. Run the applicable checks locally.
+4. Write a clear pull request description that includes:
+   - What changed
+   - Why the change is needed
+   - How it was tested
+   - Any follow-up work or known limitations
+5. Link related issues using GitHub keywords such as `Fixes #123` or `Refs #123`.
+6. Respond to review feedback with follow-up commits.
+
+## Reporting issues
+
+When opening an issue, include:
+
+- Operating system and version
+- Node.js, pnpm, and Rust versions when relevant
+- The exact command you ran
+- Expected behavior
+- Actual behavior and logs/errors
+- Minimal reproduction steps
+
+Clear reports and focused pull requests help maintainers review contributions faster.

README.md

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 # agent-browser
 
+[![CI](https://github.com/dextonai/agent-browser/actions/workflows/ci.yml/badge.svg)](https://github.com/dextonai/agent-browser/actions/workflows/ci.yml)
+
 Browser automation CLI for AI agents. Fast native Rust CLI.
 
 ## Installation