A web UI for Pi coding agent. Runs as a Pi extension inside your existing Pi process — no separate server needed.
Forked from deflating/tau. Thanks to the original author for building the foundation. Renamed to pi-web-ui with significant changes including single-session scope, removed auth, redesigned sidebar.
Pi Web UI connects to your running Pi session and gives you a browser interface. Same session, same messages, same tools — just a different screen. Type in the terminal or the browser, both stay in sync.
- Real-time streaming — messages, tool calls, and thinking blocks
- Conversation tree sidebar — inspect the current session tree, select nodes without changing drafts, branch from user messages, and continue from branch ends
- React UI — Vite, Tailwind, shadcn/ui, AI Elements
- Markdown rendering — Streamdown for code blocks, math, Mermaid
- No extra process — the Pi extension is the server
Install from GitHub:
pi install git:github.com/kkkiio/pi-web-uiOr from npm:
pi install npm:@kkkiio/pi-web-ui- Start Pi in your terminal
- Type
/webui— the extension uses the execution context to resolve the URL, enable advanced features, and open the browser
The server starts automatically when a Pi session begins and shuts down when the session ends.
- Streaming text and thinking/reasoning blocks
- Tool call display with expand/collapse
- Image attachments with paste, drop, and preview
- Branch from user messages and continue from branch ends via
navigate_treein the current session tree (requires/webuicommand context) - Follow-up messages while the agent is streaming
- Current model label and searchable model picker
- Thinking level cycle button
- Context-window visualization and compact suggestion
- Sidebar with the current conversation tree
- Search, expand/collapse, and select tree nodes without overwriting the input draft
- Branch from user messages when you want to edit an earlier prompt and continue in the same session
- Continue from non-user branch ends when you want to resume an existing branch without changing the draft
- Command palette: compact, export HTML, session stats, tool toggle
- Light, dark, and system theme modes
Environment variables (set before starting Pi):
| Variable | Default | Description |
|---|---|---|
PI_WEB_UI_PORT |
3001 |
Server port |
PI_WEB_UI_HOST |
127.0.0.1 |
Bind address |
PI_WEB_UI_DISABLED |
0 |
Set to 1 to disable |
PI_WEB_UI_STATIC_DIR |
(bundled) | Override static files path |
PI_CODING_AGENT_DIR |
~/.pi/agent |
Override Pi config directory |
PI_CODING_AGENT_SESSION_DIR |
(derived) | Override Pi session storage directory |
Or in ~/.pi/agent/settings.json:
{
"pi-web-ui": {
"port": 3001,
"host": "127.0.0.1"
}
}Pi Web UI follows Pi's PI_CODING_AGENT_DIR and PI_CODING_AGENT_SESSION_DIR
overrides when reading settings and current session state.
/webui-stop Stop the server
/webui-start Start it again
To prevent auto-start:
PI_WEB_UI_DISABLED=1 piPi Web UI binds to 127.0.0.1 by default — accessible only from your local machine. For remote access, use tailscale serve or a reverse proxy with TLS. There is no built-in authentication; it's unnecessary for local-only access and insecure over cleartext.
Pi Web UI is a Pi extension. When Pi starts a session, the extension starts an HTTP + WebSocket server inside the Pi process. The extension subscribes to Pi events and forwards them to the browser. Commands from the browser execute via the extension API using the ExtensionContext that Pi provides.
graph LR
A[Pi TUI<br/>terminal] <-->|Pi events| B[Pi Process<br/>pi-web-ui extension]
B <-->|HTTP + WS :3001| C[Browser]
git clone https://github.com/kkkiio/pi-web-ui.git
cd pi-web-ui
npm install
npm run build:web
PI_WEB_UI_STATIC_DIR=$(pwd)/dist piFor frontend development, run Pi in one terminal, then:
npm run dev:webOpen http://localhost:4444; Vite serves the React UI and proxies /api and /ws to the extension on localhost:3001.
MIT