Pi — this one is (y)ours

An unofficial, personal VS Code chat UI for the Pi coding agent.

Disclaimer. I have no affiliation with pi.dev. I genuinely appreciate their work — this extension simply builds a GUI on top of Pi’s public RPC protocol. I made it for myself and I’m sharing it for anyone who wants to use it. It is provided as-is, with no warranty, and “Pi” belongs to its respective owners.

The Pi coding agent, natively in VS Code — the same power as the pi terminal, in a clean chat UI with editor-tab conversations and a session launcher.

What it is

Pi RPC embeds the Pi coding agent inside VS Code. It hosts real Pi sessions on a shared runtime in the background and gives you a native GUI on top:

• Parallel chats — every chat tab is its own independent Pi session on a shared runtime worker pool (with per-chat process fallback if the shared host cannot start). Fire off a long task in one chat and keep working in another; closing a tab tears down just that session.
• A sidebar launcher with an instant New Chat (a draft session is prewarmed for you), your saved chats, an Other projects group with every chat from every project, live status badges, and full-text search across chat content.
• Mission Control — the status bar shows how many chats are open / generating / waiting for your approval; background chats that need permission raise a notification.
• Turn review — when a turn changes files, review a consolidated list: open before↔after diffs, revert one file, or revert everything the turn touched.
• Edits fork, visibly — editing a message re-runs the chat on a fork in the same tab; Pi: Show Chat Versions opens any earlier version.
• Quick switcher (Cmd/Ctrl+Alt+P), aggregate usage/cost across open chats, export/copy conversations, and many Pi TUI workflows: models, thinking levels, slash commands, attachments/context, compaction, retry, usage, diagnostics.
• Watch & drive from your phone — a Connect a phone button mirrors the live chat to a phone browser (opt-in via piRpc.remote.enabled).

It talks to Pi over Pi’s documented RPC protocol, so your existing Pi setup, models, sessions, skills, prompts, and extensions all work unchanged.

Prerequisites

Have pi installed already? It's used as-is — the extension detects pi on your PATH and runs on it directly (no duplicate copy, no surprise npm installs; you manage updates). No pi yet? Either install it yourself (npm install -g @earendil-works/pi-coding-agent) or set piRpc.autoInstall: true and the extension installs the newest Pi version supported by its native host into its own storage. Auto-install is off by default — nothing is ever downloaded without your consent.

The native host supports the audited Pi SDK versions 0.99.1, 0.99.2, 1.0.0, 1.0.4, 1.1.0, 1.2.0 and 1.3.0. Other versions and custom wrappers use stock RPC; features requiring the native SDK report their unsupported capability.

Resolution is deterministic: an explicit piRpc.executable wins, otherwise the current pi on PATH wins, and only then can a compatible managed installation be used. With piRpc.autoInstall: false, the extension performs no npm check, download, replacement, or staged-update application.

You also need:

1. Authenticate Pi once (either is fine):
   • Subscription / OAuth: run pi in a terminal and use /login, or
   • API key: export your provider key, e.g. export ANTHROPIC_API_KEY=…
2. Open a folder in VS Code.

Prefer your own install? Set piRpc.piSource to external and (optionally) Settings → Pi RPC → Pi Executable Path.

How it works

VS Code
├─ Sidebar (Pi)            New Chat · search (titles + content) · saved chats · Other projects
└─ Editor tabs "Pi Chat"   one INDEPENDENT Pi session per tab — chats run in parallel
        │
        ▼
shared Pi runtime pool     configurable workers host sessions (per-session extensions/MCP);
                           a draft session is prewarmed so New Chat opens instantly

• The first chat boots the shared runtime; every further chat attaches in the background while the tab paints immediately (animated loader, then the composer goes live).
• Sessions are named Session N by default and can be renamed; the real session id stays internal. Closing a tab tears down only that chat's session — never the file.
• Each message edit forks the session and stays in the same tab; stale fork ancestors are collapsed in the sidebar and reachable via Pi: Show Chat Versions.

Getting started

1. Install this extension and open a project folder (your PATH pi is auto-detected; otherwise install Pi or enable piRpc.autoInstall).
2. Log in once if you haven't (see Prerequisites).
3. Click the Pi icon in the Activity Bar → New Chat.
4. Type your message and press Enter to send (Shift+Enter for a newline).

Features (Pi workflows in a GUI)

The Outbox holds follow-ups in the extension until sending. If delivery cannot be confirmed, it pauses pending messages and never automatically resends the uncertain message. Terminal-only extension interfaces show an unsupported notice in chat.

While Pi is working

In native editor chat tabs, your sent message stays visible with a Working… indicator while Pi prepares a reply. The current empty assistant container and its π role label are deferred until the first meaningful reply content arrives; the reply then streams normally, without waiting for completion. Thinking, tool activity, errors and completed history (including empty-reply Retry/Logs feedback) remain available.

Watch & drive from your phone

You can mirror a live chat to your phone — handy for kicking off a long task and keeping an eye on it (or nudging it) from the couch.

One-time setup (Settings → Pi RPC → Remote):

• Broker URL — the address of your Pi relay (e.g. https://pi.fromlab.work).
• Host Secret — the shared secret your relay expects.

Each session:

1. Open a chat, then click 📱 Connect a phone in the Pi sidebar (or run Pi: Start Remote Session from the Command Palette).
2. A pairing panel opens with a QR code and a 6-digit PIN. It stays open until you stop.
3. On your phone, scan the QR (or open the link) and enter the PIN.
4. The phone shows the conversation live. Tap Take control to send prompts; VS Code pops a confirmation when a device connects.
5. Click Stop session in the panel (or Pi: Stop Remote Session) when you’re done.

Security. The relay never sees your code or Pi — it only forwards messages. Pairing is QR + PIN, a per-session token is minted server-side and held only on the phone (never in a URL), sessions expire, and only one device can drive at a time.

Keyboard

Undo after sending restores the submitted text into the composer for editing. It does not retract or resend the message. Ctrl+Shift+Z also supports Redo.

Chat menus

In the current source tree, the sidebar ellipsis menu groups actions as:

• Chat — Review last turn, Chat versions, Export chat
• Configure — Extensions…, Skills…, Prompts…, Agent instructions…, Working Animation (opens the existing animation selector for piRpc.workingAnimation; choose braille, dots, bars, earth, moon, or dolphin there; braille is the default, and the picker describes your current preference)
• System — Restart π

The sidebar always shows the Agentic chat list. Opening a chat or starting a new one uses a native editor tab. The editor-title Pi Chat Actions menu additionally offers rename, retry (including with another model), find, copy as Markdown, thinking level, compaction, attachments, health, logs, and help. Model and thinking controls live in the composer status chip; there is no composer gear. With Pi 1.2.0 or 1.3.0, opening model selection refreshes OpenRouter's key-specific models in the background while cached choices remain usable. Discovery does not run during activation or warmup. Offline mode keeps cached models; a failed refresh shows a clear fallback message in the picker.

Settings worth knowing (Settings → Pi RPC)

• Working Animation — choose one of the six working glyph styles (default: braille). The separate decorative π logo has a fixed shape; this setting does not change it. Its breathing motion and the glyph animation respect reduced motion.
• Typewriter Speed — how smoothly streamed answers type out (off / slow / normal / fast).
• Chat Font Family / Size — the transcript font.
• Notify On Complete — ping when a long response finishes and the chat isn’t focused.
• Auto Compact Mode / Percent — piRpc.autoCompact.mode defaults to auto; piRpc.autoCompact.percent defaults to 75% of the model's detected context window. The old piRpc.autoCompactThreshold setting is deprecated.
• CodeLens Enabled — the inline “Ask Pi” action above functions/methods.
• Remote → Broker URL / Host Secret — required for Connect a phone.
• Pi Executable Path — set this if pi isn’t on your PATH.

Troubleshooting

• Stuck on “Connecting…” → use Show Health in the editor-title menu or Command Palette, or Restart π. Make sure pi --version works in a terminal and that you’ve logged in.
• “Pi is still connecting…” when using / → wait a moment; slash commands need a live session.
• Wrong/old Pi → set the Pi Executable Path setting to the exact binary.
• Phone won’t pair → make sure Remote → Broker URL and Host Secret are set, and pair before the code expires. If it says the code expired, just run Start Remote Session again.
• Phone connected but blank → open (or click into) a chat in VS Code so there’s an active conversation to mirror.

Privacy & security

• Runs entirely locally against your own pi process — this extension adds no telemetry.
• Respects VS Code Workspace Trust: in a restricted workspace, chat is read-only and mutating actions stay disabled until you trust the folder.
• Diagnostics exports are redacted and never include transcript text, drafts, or secrets.
• Pi extension prompts use inline selection, confirmation, input and multiline editor controls with Cancel. Suggested composer text always waits for Use or Keep, including an empty composer; later typing and attachments stay protected. The synchronous native getEditorText() getter remains unavailable over RPC and returns an empty string, matching Pi's terminal RPC contract.

Notes

• Workspace folders are isolated. piRpc.runtimeWorkers sizes the shared worker pool (auto, or 1–8); disabling shared runtime or a host startup failure uses per-chat processes.
• Agentic is the sole interface in 0.2.22. Its 27 supported command paths have automated coverage, with additional installed VS Code checks for chat-list navigation, deletion and composer layout. Terminal-only extension UI and physical OS input methods retain their documented limits; this does not establish universal native TUI parity.
• The Activity Bar icon and gallery logo are an original Pi × VS Code fusion mark.

Credits & affiliation

This is an independent, unofficial project. I am not affiliated with pi.dev and claim no endorsement by them. All credit for the Pi coding agent goes to its authors at pi.dev; this extension only talks to Pi over its documented RPC protocol. Built for personal use and shared freely for anyone who finds it useful.

License

MIT