Browser Kitten

An agent for the browser you already use.
Read signed-in pages, take action, create files, and follow up locally.

Quick start · Configuration · Documentation · Current limits · Contribute · Issues

--- Browser Kitten is an MIT-licensed Chrome MV3 extension with an agent in the side panel. It works with your existing browser session and keeps conversations, workspace files, and follow-up tasks on this computer. Model and other provider requests use the services you configure. **Current source version: 1.2.0 · Load unpacked · No build step for installation.** ## What you can do | Capability | In practice | | :--- | :--- | | **Read & research** | Understand pages you are signed in to, select relevant content, and collect findings. | | **Act on pages** | Delegate clicks, form entry, and navigation to a separately configured execution model. | | **Create deliverables** | Save documents, HTML pages, data, and files in a session workspace. | | **Follow up** | Arrange local checks, preserve progress, and manage ongoing tasks from a collapsible drawer. |

See the actual side panel — light & dark

Actual Browser Kitten side panel in light mode, with an unsent example task

_{Captured from the extension in a fresh browser profile. The example is an unsent draft, not a completed run.}

## Quick start 1. **[Download the current source ZIP](https://github.com/Player-YN/BrowserKitten/archive/refs/heads/main.zip)** and extract it into a folder you will keep. 2. Open `chrome://extensions` in desktop Chrome, enable **Developer mode**, then choose **Load unpacked**. Select `BrowserKitten-main`, the folder that directly contains `manifest.json`. 3. Pin **Browser Kitten**, refresh an ordinary website tab, open the side panel, and configure your providers below. You do **not** need Node.js, Python, npm, or a build command to install it. The source folder itself is the extension load root. > **Trying the latest work?** The download above follows `main`. The separate GitHub Releases page may contain older tagged versions. For the full walkthrough, permissions, update instructions, and troubleshooting, see **[Getting started](docs/GETTING_STARTED.md)** · **[中文安装指南](docs/GETTING_STARTED.zh-CN.md)**. ## Configuration Open **Settings** from the side-panel menu. For a bring-your-own-key setup: | Setting | Needed for | Enter | | :--- | :--- | :--- | | **Inference** | Planning, analysis, and tool calls | Base URL, API key, and a tool-capable model ID | | **System1** | Page clicks and form interactions | A separate execution-model configuration using an OpenAI-compatible `/chat/completions` endpoint | | Image / Transcription / Search | Additional media and web capabilities | Configure only the services you need | Inference and System1 can use the same provider, but must be configured separately. The unpacked build accepts your own keys without a Browser Kitten subscription; the external providers still charge for usage. Account-hosted services are optional and depend on the separate backend. Try a small first task: > Summarize the current page and save its key findings as a document. **Enter** inserts a newline. **Ctrl+Enter / Cmd+Enter** sends. Enable page scripts and capture permissions only when the task needs them; see the [permission guide](docs/GETTING_STARTED.md#permissions). ## Local follow-ups Describe the goal, permitted actions, reporting conditions, and when to stop. The agent can arrange or remove wakeups within that goal. Manage them in the **collapsible task drawer above the input**. - Chrome must remain running and the computer awake. Closing the side panel is fine. - Checks run on a minute-scale schedule; immediate webpage-event subscriptions are not implemented. - New scheduled tasks can stay quiet when nothing meaningful changes, and report actions, changes, or requests for help. See [follow-up behavior and controls](docs/GETTING_STARTED.md#local-follow-ups). ## Current limits - This is a local browser extension; there is no cloud execution environment or native OS / terminal control. - The host currently enforces **per-tab leases** and **per-session execution slots**, rather than a global browser lock. Automatic grouping of all agent-controlled website tabs is not implemented. Run one browser-operating task at a time. - Restricted Chrome pages and the Web Store are not ordinary automation targets. Browser smoke tests do not establish success on every website or with every model. - Settings and workspaces are local to this Chrome profile. They do not automatically move to another computer. Relevant task content may be sent to your configured providers. Read [updates and data](docs/GETTING_STARTED.md#updates-and-data) before replacing an installation. ## Documentation | Start here | Go deeper | | :--- | :--- | | [Getting started](docs/GETTING_STARTED.md) · [安装指南](docs/GETTING_STARTED.zh-CN.md) | [Architecture](AGENTS.md) · [Agent runtime](src/agent/AGENTS.md) *(中文)* | | [Documentation index](docs/README.md) | [Tools & Workflow](docs/PERSONAL_LIBRARY.md) · [Workflow contract](docs/WORKFLOW_V1.md) *(中文)* | | [Troubleshooting & support](SUPPORT.md) | [UI design](Design.md) · [Media](docs/CHAT_MEDIA_INPUT.md) *(中文)* | | [Changelog](CHANGELOG.md) | [Security policy](SECURITY.md) · [Third-party notices](THIRD_PARTY_NOTICES.md) | ## Contributing Bug reports, documentation fixes, and focused pull requests are welcome. Start with **[CONTRIBUTING.md](CONTRIBUTING.md)** for setup and checks. Use a [bug report](https://github.com/Player-YN/BrowserKitten/issues/new?template=bug_report.yml) or [feature request](https://github.com/Player-YN/BrowserKitten/issues/new?template=feature_request.yml) to give maintainers useful context. Please follow the [Code of Conduct](CODE_OF_CONDUCT.md). Report vulnerabilities through [private security reporting](https://github.com/Player-YN/BrowserKitten/security/advisories/new), rather than a public issue. No response-time commitment is implied. ## License & acknowledgments [MIT](LICENSE) © 2026 Yiteng (Player-YN). Built with open-source projects including Vercel AI SDK, QuickJS, esbuild, Zod, Lucide, and fflate. See [third-party notices](THIRD_PARTY_NOTICES.md) for their respective licenses.