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@unmodeled-tyler/vessel-browser

MCP browser for agents with durable state

Vessel Browser is a Chromium-based browser that lets agents act on the web while keeping the human in the loop. It combines a visible browser UI with MCP access, persistent runs, approvals, checkpoints, and browser state that survives longer sessions. It also supports built-in chat, bookmarks with agent metadata, page change tracking, and a supervisor sidebar for reviewing or steering work. External harnesses can connect through the local MCP server or the `vessel-browser-mcp` proxy.

130 stars12 forksTypeScriptUpdated 22d ago
Who it's for

Builders who want an agent to browse, research, and fill forms in a visible browser instead of a hidden automation run.

What it delivers

You can let an agent work across long web sessions without losing context or control.

What it does

Visible browser control

The agent works in a normal browser window, so you can see pages, follow along, and take over when needed.

MCP server and proxy

External agents connect through the local MCP server, or through `vessel-browser-mcp --stdio` for stdio-based harnesses.

Durable sessions and runs

Vessel keeps conversation threads, run history, checkpoints, bookmarks, and page changes across interrupted work.

Human approvals and undo

You can approve once, approve by run or domain, reject with steering, and undo the last mutating action.

Agent-friendly browsing tools

The browser includes reader mode, form autofill, page diff tracking, page highlights, bookmarks, and research workflows.

How to get it

  1. 1Run
    npm install -g @quanta-intellect/vessel-browser
    vessel-browser
  2. 2Or run it directly without installing
    npx @quanta-intellect/vessel-browser
  3. 3Run
    curl -fsSL https://raw.githubusercontent.com/unmodeled-tyler/vessel-browser/main/scripts/install.sh | bash
  4. 4Vessel development uses Node.js 22. If you use fnm, run fnm use from the repo root to…
    fnm use
    npm install
    npm run dev
  5. 5After install
    vessel-browser
  6. 6Example
    llama-server -m /path/to/model.gguf --port 8080 --ctx-size 32768

README

quanta-intellect-logo-transparent

Get it from the Snap Store Vessel Browser from Quanta Intellect - The browser where agents drive and humans supervise | Product Hunt

Vessel: Your AI-Powered Browser

Vessel is a simple, clean web browser with an AI assistant built in. Browse the web normally, then ask Vessel to help research, navigate pages, summarize what you are reading, fill forms, or keep track of longer tasks.

Unlike invisible browser automation, Vessel shows you what the AI is doing in a real browser window. You can follow along, approve important actions, pause or redirect the work, and take over whenever you want.

  • A familiar browser, with AI help nearby — tabs, bookmarks, reader mode, downloads, and a sidebar assistant for web tasks
  • Great for longer browsing sessions — durable conversation threads, a cross-source run inbox, named sessions, checkpoints, notes, bookmarks, and page changes make interrupted work recoverable
  • You stay in control — review what the AI is doing, approve sensitive actions once or for a scoped run/domain, reject with steering, undo recent changes, and switch back to manual browsing at any time
  • Open source and extensible — built on Chromium, with advanced automation support for MCP clients and agent tools when you need it

Linux is the most mature install target today. macOS release packaging is available from source.

Vessel is in active development. Treat it as early software, especially for sensitive browsing or account access.

https://github.com/user-attachments/assets/0a72b48a-873a-4eb0-b8f2-23e34d8472c4

Quick Start

Want the complete AI toolkit from day one? Start a 7-Day Free Trial of Vessel Premium — $5.99/mo.

Fastest Install Today

Linux AppImage from GitHub Releases:

  1. Download the latest Vessel-<version>-x64.AppImage
  2. Mark it executable: chmod +x Vessel-*.AppImage
  3. Launch it: ./Vessel-*.AppImage
  4. Open Settings (Ctrl+,) to choose your AI provider and review advanced connection options

Install via npm

npm install -g @quanta-intellect/vessel-browser
vessel-browser

Or run it directly without installing:

npx @quanta-intellect/vessel-browser

Source Install

curl -fsSL https://raw.githubusercontent.com/unmodeled-tyler/vessel-browser/main/scripts/install.sh | bash

Development From Source

Vessel development uses Node.js 22. If you use fnm, run fnm use from the repo root to pick up .node-version.

fnm use
npm install
npm run dev

If you want extra local AI tracing in development, create an optional src/main/telemetry/trace-logger.local.cjs file. Vessel will load it only in local dev builds, and packaged production builds ignore it.

Why Vessel?

Most AI tools can answer questions about the web. Vessel is for actually working on the web: reading pages, following links, comparing information, filling forms, tracking changes, and keeping longer browsing sessions organized.

Vessel Browser supervisor sidebar showing agent workflow controls Vessel Browser command bar and agent-driven page interaction Vessel Browser persistent session and checkpoint interface Vessel Browser integrated chat assistant with browser tools

Vessel keeps that work visible. The AI uses a real browser, so you can see the pages it opens, the choices it makes, and the places where it needs your approval. You are never stuck watching a hidden automation run or guessing what happened after the fact.

For power users and developers, the same foundation also supports external agents, MCP clients, persistent sessions, checkpoints, and browser automation workflows.

Features

  • AI-assisted browsing — ask Vessel to help with research, page reading, navigation, form work, and multi-step web tasks
  • Human-visible browser UI — pages render like a normal browser so AI activity stays legible instead of disappearing into a hidden run
  • Command Bar (Ctrl+L) — a secondary operator surface for harness-driven workflows and future runtime commands
  • Supervisor Sidebar (Ctrl+Shift+L) — live supervision across ten tabs, including a durable Run Inbox, conversation Threads, approvals, checkpoints, changes, and Research
  • Chat Assistant — built-in conversational AI in the sidebar Chat tab; supports Anthropic, OpenAI, Ollama, llama.cpp, Mistral, xAI, Google Gemini, OpenRouter, and any OpenAI-compatible endpoint; reads the current page automatically; has full access to the same browser tools as external agents; multi-turn session history; configure provider, model, and API key in Settings
  • Skills (Premium) — reusable browser skills in the sidebar Skills tab; import, view, run, or delete skills the built-in agent can use for research, shopping, and site-specific workflows
  • Research Desk (Beta) — a dedicated sidebar Research tab for structured research reports; start with a topic, complete an in-tab briefing, let Vessel draft research objectives, approve the plan, then dispatch browser sub-agents to collect source-backed claims and synthesize a markdown-exportable report. Starting the brief is free; plan approval, sub-agent execution, and report export require Vessel Premium.
  • Dev Tools Panel (F12) — inspect console output, network requests, and MCP/agent activity in a resizable panel at the bottom of the window; export logs by category and date range as JSON
  • Browser Basics For Long Runs — pinned tabs stay compact at the front of the tab strip and are protected from accidental close; tab groups can be color-coded and collapsed; audible tabs show audio indicators with mute controls; open additional browser windows with Ctrl+N; print the active page with Ctrl+P or save it directly as PDF with Ctrl+Shift+P
  • Action Undo / Rollback — restore the browser to the session snapshot captured immediately before the last successful mutating agent action; available from the Supervisor tab and through the undo_last_action tool
  • Durable Run Inbox — Chat, MCP, scheduled, and Research work share one persisted lifecycle with status filters, parent/child research runs, redacted inputs, outputs, errors, and tab context
  • Persistent Conversation Threads — group multiple independent chats inside named threads; each chat gets an AI-generated title after its first completed exchange and can be reopened or retitled, while threads can be renamed, archived, or deleted; archived threads follow the configured history period
  • Scoped Approval Policies — approve once, approve for a run, approve for a domain, or reject and steer; explicit denies take precedence and expired scoped rules are ignored
  • Agent-Meaningful Bookmarks — bookmarks carry structured context the agent can read and act on: intent (what the page is for), expectedContent (what to expect on the page), keyFields (important form fields), agentHints (arbitrary directives), and a stored pageSchema; humans can create and edit this metadata directly in the Bookmarks tab, and all fields are searchable
  • Portable Bookmark Export — export browser-compatible Netscape HTML for import into Chrome, Firefox, Safari, Edge, Brave, and other browsers; optionally include Vessel notes/agent metadata, or export a full-fidelity Vessel JSON archive
  • Page Schema Inference — Vessel automatically infers a typed schema for every page: pageType (article, product, form, search, checkout, login, dashboard), primaryEntity (structured fields for products and articles), formFields (with names, types, labels, selectors), and actionButtons (with inferred intents: submit, addToCart, login, etc.); schema is attached to every content extraction result
  • Bookmarks for Agents — save pages into folders, attach one-line folder summaries, and search bookmarks over MCP instead of dumping the entire library
  • Named Session Persistence — save cookies, localStorage, and current tab layout under a reusable name, then reload it after a restart
  • Annotated Checkpoints — capture and restore short-lived browser recovery points with names and editable notes, so humans and agents can mark why a checkpoint matters before risky flows
  • Page Highlights — agents can visually highlight text or elements on any page with labeled, color-coded markers that persist across navigation; highlight count and navigation controls appear in the sidebar; cleared explicitly or via tool call
  • Agent Transcript Dock — floating transcript overlay anchored to the browser chrome; configurable display modes (off, summary, full) set in Settings; shows live agent thinking and status updates without occupying sidebar space
  • Workflow Flow Tracking — agents can declare a named multi-step workflow at runtime using flow_start; progress is tracked step-by-step with flow_advance and visible in the sidebar throughout execution
  • Structured Page Visibility Context — extraction can report in-viewport elements, obscured controls, active overlays, and dormant consent/modal UI
  • Popup Recovery Tools — agents can explicitly dismiss common popups, newsletter gates, and consent walls instead of brute-forcing generic clicks
  • Form Autofill Profiles — save reusable personal or work profiles in Settings and fill common contact, address, and organization fields on the current page; Vessel matches fields using labels, names, placeholders, and autocomplete hints
  • Page Diff / "What Changed?" — Vessel remembers the last snapshot of a page and surfaces a Changed badge in the address bar when the title, headings, or main content differ on a later visit; expand it to see a compact summary of what changed since the last snapshot
  • What Changed Timeline (Premium) — the sidebar Changes tab keeps a per-page history of recent change bursts, showing when each update was detected and a compact summary of what changed
  • Per-Tab Ad Blocking Controls — tabs default to ad blocking on, but agents can selectively disable and re-enable blocking when a page misbehaves
  • Domain Policy — allowlist or blocklist domains globally in Settings; agents cannot navigate to blocked domains
  • Agent Credential Vault (Premium) — encrypted credential storage for agent-driven logins; credentials are filled directly into login forms via a "blind fill" pattern and are never sent to AI providers; user consent dialog before every use; TOTP 2FA support; domain-scoped access; append-only audit log
  • Screenshot & Visual Analysis (Premium) — take a full-page screenshot and pass the image directly to the AI for visual layout analysis; useful when text extraction fails on heavy or canvas-rendered pages
  • Obsidian Memory Hooks (Premium) — optional vault path for agent-written markdown notes, page captures, and research breadcrumbs
  • Runtime Health Checks — startup warnings for MCP port conflicts, unreadable settings, and user-data write failures
  • Reader Mode — extract article content into a clean, distraction-free view; toggle on and off from the address bar
  • Focus Mode (Ctrl+Shift+F) — hide all chrome, content fills the screen
  • Resizable Panels — drag the sidebar edge to resize; width persists across sessions
  • Minimal Dark Theme — warm dark grays, restrained accent color, and no pure black/white

Reliability, History, and Approvals

The Supervisor sidebar now keeps longer-running work understandable across Chat, external MCP agents, scheduled jobs, and Research:

  • Open Runs to filter work that needs attention, is active, failed, completed, or comes from any source. Each run has a chronological timeline with status changes, approvals, outputs, errors, and relevant tab context; records can be exported as Markdown or JSON or deleted from Vessel.
  • Open Threads to organize multiple chats under a named topic. Chats can be reopened or retitled independently, while their parent thread can be renamed, archived, or deleted. New chats receive a generated title after their first completed exchange.
  • Approval cards show the action, redacted arguments, domain, and whether undo is available. You can approve once, approve matching work for the current run or domain, reject, or reject with written steering. Persisted scoped rules remain visible in Supervisor and can be removed there.
  • If Vessel closes while a run is active or waiting for approval, that run is marked interrupted on the next launch instead of being left misleadingly active. Vessel does not claim to resume or retry the unfinished execution automatically.
  • Terminal run history and archived threads follow historyRetentionDays (90 days by default; supported values are 7, 30, 90, 180, 365, or null for no automatic expiry). Active runs and unarchived threads are preserved.

Conversation history is encrypted through Electron's safeStorage API when encryption is available. If secure storage is unavailable, Vessel keeps conversations in memory for that session instead of writing plaintext chat history. Run records redact sensitive argument fields and limit stored output size before persistence or export.

Positioning

Most browsers treat automation as secondary and assume a human is the primary actor. Vessel is the opposite: it is the browser for the agent, with a visible interface that keeps the human in the loop.

That means the product should optimize for:

  • persistent browser state across tasks and sessions
  • clear visibility into what the agent is doing right now
  • lightweight human intervention instead of constant manual driving
  • a browser runtime that can serve long-lived agent systems such as Hermes Agent or OpenClaw-style harnesses

Stack

LayerTechnology
EngineChromium (Electron 40)
UI FrameworkSolidJS
LanguageTypeScript
Buildelectron-vite + Vite
AI ControlExternal agent harnesses (Hermes Agent, OpenClaw, MCP clients) + built-in chat (Anthropic, OpenAI, Ollama, llama.cpp, and any OAI-compatible endpoint)
Content Extraction@mozilla/readability

Architecture

Main Process                                  Renderer (SolidJS)
├── TabManager (WebContentsView[])            ├── TabBar, AddressBar
├── AgentRuntime (session + supervision)      ├── CommandBar (secondary surface)
├── Run, conversation, and policy managers    ├── AI Sidebar (Supervisor/Runs/Threads/Chat/...)
├── MCP server for external agents            ├── DevTools Panel (Console/Network/Activity)
├── AI providers (Anthropic + OAI-compatible) ├── Agent Transcript Dock
├── Bookmarks, checkpoints, and page history  └── Signal stores (runtime/runs/conversations/policies/...)
└── IPC handlers ◄──contextBridge──► Preload API

Each browser tab is a separate WebContentsView managed by the main process. The browser chrome (SolidJS) runs in its own view layered on top. All communication between renderer and main goes through typed IPC channels via contextBridge.

The sidebar Skills tab renders skill forms entirely in the renderer and passes the rendered prompt to the built-in agent via the same query() path used by the Chat tab — no additional IPC surface is needed. The Changes tab reads the current page's diff timeline through IPC and unlocks persisted history for Premium users. The Research tab has a dedicated IPC surface for its state machine: briefing is available to everyone, while objective approval, parallel browser sub-agents, report synthesis, and markdown export are Premium-gated during the beta.

Getting Started

The installer:

  • clones or updates Vessel into ~/.local/share/vessel-browser
  • installs dependencies and builds the app
  • creates a vessel-browser launcher in ~/.local/bin
  • creates a vessel-browser-launch helper in ~/.local/bin
  • creates a vessel-browser-update helper in ~/.local/bin
  • creates a vessel-browser-status helper in ~/.local/bin
  • creates a desktop entry for Linux app launchers
  • writes ~/.config/vessel/vessel-settings.json with MCP port 3100
  • writes ~/.config/vessel/mcp-stdio-snippet.json
  • writes ~/.config/vessel/mcp-http-snippet.json
  • installs a vessel-browser-mcp helper that can run as a stdio-to-HTTP proxy (--stdio) or print config snippets
  • prints the exact recommended stdio MCP snippet to paste into your harness config

The packaged AppImage path:

  • does not require a local Node/Electron toolchain
  • uses the packaged Vessel app icon and metadata
  • is the recommended path for early adopters who just want to run Vessel

Windows packaged releases:

  • use the Vessel-<version>-x64-setup.exe NSIS installer
  • can be installed over an existing Vessel install when upgrading
  • preserve Vessel app data during the normal upgrade path

You do not need to uninstall Vessel before installing a newer Windows release. Uninstall first only if you are recovering from a broken install or intentionally removing local Vessel data.

After install:

vessel-browser
# Use the pinned Node.js 22 runtime
fnm use

# Install dependencies
npm install

# If Electron download fails, use a mirror:
ELECTRON_MIRROR="https://npmmirror.com/mirrors/electron/" npm install

# Development (with HMR)
npm run dev

# Production build
npm run build

# Smoke-test the MVP release path
npm run smoke:test

# Package an unpacked Linux app
npm run dist:dir

# Package a Linux AppImage
npm run dist

# Package an unpacked universal macOS app bundle (run on macOS)
npm run dist:mac:dir

# Package universal macOS DMG + ZIP artifacts (run on macOS)
npm run dist:mac

# Verify a universal macOS build contains Intel and Apple Silicon slices
npm run verify:mac:universal

# Package signed macOS DMG + ZIP artifacts (run on macOS with signing set up)
npm run dist:mac:signed

Notes:

  • npm run dev still launches the stock Electron binary, so Linux may continue showing the default Electron gear icon in development
  • packaged builds created with npm run dist / npm run dist:dir use the Vessel app icon
  • npm run build:icon:mac regenerates resources/vessel-icon.icns from resources/vessel-icon.png for macOS packaging
  • npm run dist:mac and npm run dist:mac:dir build universal macOS artifacts by default, so the same app runs natively on Intel and Apple Silicon Macs
  • npm run dist:mac:x64 and npm run dist:mac:arm64 are available when you need smaller architecture-specific test artifacts
  • npm run verify:mac:universal uses lipo to confirm the packaged app executable and Electron framework include both x86_64 and arm64 slices
  • npm run dist:mac, npm run dist:mac:dir, npm run dist:mac:x64, and npm run dist:mac:arm64 intentionally disable auto-signing so local packaging works on any Mac without keychain setup
  • npm run dist:mac:signed and npm run dist:mac:dir:signed build universal artifacts and use normal electron-builder signing discovery; if your login keychain has duplicate Apple certs, clean those up or use a dedicated keychain before running the signed path
  • signed builds are still not notarized by this repo out of the box, so Gatekeeper warnings remain until notarization is added for release publishing
  • the tracked smoke test runs typecheck, build, the MCP stdio proxy regression check, and the Electron navigation regression harness
  • for headless CI, run the smoke test under xvfb-run -a npm run smoke:test

Setting up Vessel for Hermes Agent or OpenClaw

Vessel is designed to act as the browser runtime that your external agent harness drives.

  1. Launch Vessel
  2. Open Settings (Ctrl+,) to confirm MCP status, copy the endpoint, or change the MCP port
  3. Optional: set an Obsidian vault path, create autofill profiles, or adjust session preferences
  4. Start Hermes Agent or OpenClaw and point it at Vessel — the easiest way is vessel-browser-mcp --stdio as the MCP command (auth is resolved automatically), or connect directly to http://127.0.0.1:<mcpPort>/mcp with the bearer token from ~/.config/vessel/mcp-auth.json
  5. Use the Supervisor panel in Vessel's sidebar to pause the agent, change approval mode, review pending approvals, checkpoint, undo the last mutating action, or restore the browser session while the harness runs
  6. Open Runs to inspect or export activity from Chat, MCP, scheduled jobs, and Research; use Threads to reopen and organize durable conversations
  7. Use the Bookmarks panel to organize saved pages into folders, edit agent-facing bookmark metadata, export bookmarks for other browsers, and expose saved pages back to the agent over MCP

Notes:

  • Vessel exposes browser control to external agents through its local MCP server
  • The MCP endpoint supports both legacy clients and the modern 2026-07-28 protocol revision, including server/discover
  • The default MCP port is 3100
  • Hermes Agent and OpenClaw should treat Vessel as the persistent, human-visible browser rather than launching their own separate browser session
  • Vessel supports a built-in Chat tab with configurable AI provider; open Settings (Ctrl+,) and enable Chat Assistant to set a provider and model
  • The sidebar Research tab is marked Beta; use it to turn a broad research topic into a brief, approve a multi-thread plan, run browser sub-agents, and export the final report as markdown. Briefing is free, while full execution and export require Premium.
  • llama.cpp (Local) is a first-class chat provider in Settings and targets http://localhost:8080/v1 by default; Vessel auto-fetches the active model from llama-server
  • For llama-server, use --ctx-size 16384 minimum and 32768 recommended for reliable Vessel agent loops; lower values often fail once prompt, tool schema, and tool history accumulate
  • Approval policy is controlled live from the sidebar Sup

Files in the repo

Repository payload28 top-level entries
  • .github
  • .husky
  • .kilo
  • bin
  • docs
  • flatpak
  • resources
  • scripts
  • snap
  • src
  • tests
  • .editorconfig
  • .gitignore
  • .node-version
  • .prettierrc
  • CONTRIBUTING.md
  • electron-builder.config.cjs
  • electron.vite.config.ts
  • eslint.config.mjs
  • knip.json
  • LICENSE
  • package-lock.json
  • package.json
  • README.md
  • server.json
  • tsconfig.json
  • tsconfig.node.json
  • tsconfig.web.json

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