docs: add contributing guide and CI badge

CONTRIBUTING.md

@@ -0,0 +1,70 @@
+# Contributing to agent-browser
+
+Thanks for helping improve agent-browser. This guide covers the basic local workflow for documentation, TypeScript packaging, and the native Rust CLI.
+
+## Development Setup
+
+1. Install the project dependencies:
+
+```bash
+pnpm install
+```
+
+2. Install the Rust toolchain if you plan to work on the native CLI:
+
+```bash
+rustup default stable
+```
+
+3. Build the JavaScript package and native binary as needed:
+
+```bash
+pnpm build:native
+```
+
+For a faster Rust-only loop, run commands directly against the CLI crate:
+
+```bash
+cargo build --manifest-path cli/Cargo.toml
+```
+
+## Code Style
+
+- Use `pnpm` for package scripts and dependency management.
+- Use kebab-case for CLI flags, for example `--auto-connect` instead of `--autoConnect`.
+- Keep documentation updates in sync with user-facing behavior changes.
+- Run Rust formatting before submitting CLI changes:
+
+```bash
+cargo fmt --manifest-path cli/Cargo.toml -- --check
+```
+
+- Run Clippy for Rust changes:
+
+```bash
+cargo clippy --manifest-path cli/Cargo.toml -- -D warnings
+```
+
+## Testing
+
+Run the standard Rust test suite:
+
+```bash
+cargo test --profile ci --manifest-path cli/Cargo.toml
+```
+
+End-to-end tests require Chrome and run headless browser sessions. Use them when changing browser automation behavior:
+
+```bash
+cargo test --profile ci --manifest-path cli/Cargo.toml e2e -- --ignored --test-threads=1
+```
+
+## Pull Request Workflow
+
+1. Create a focused branch for your change.
+2. Keep the diff small and explain the user-visible behavior in the PR description.
+3. Link the relevant issue, if one exists.
+4. Include the commands you ran to verify the change.
+5. Update docs when changing commands, flags, environment variables, output, or workflows.
+
+For documentation-only changes, mention that no runtime tests were required and explain what was reviewed instead.

README.md

@@ -1,5 +1,7 @@
 # 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