What Tau does

The first builds of Tau set out to prove that Pi can stay the agent runtime while a desktop shell around it becomes independently extensible. This is what the workbench does with Pi today, across the core and the kits Tau ships. Other runtimes are in Runtimes and tools; other machines, the browser and the phone in Hosts, machines and devices.

• real Pi SDK session with streamed text, thinking and tool events
• recent Pi threads across projects, including project identity, the Git branch Workspace Kit supplies, live activity, and a settled shelf
• searchable recent-project modal (Cmd/Ctrl+P) and extension-provided add-project sources
• working local-folder and Git-clone project flows, plus thread search (/)
• file index marked with the working tree's changes, and a Signals event stream
• full-window diff review (Cmd/Ctrl+Shift+D) with unified and split views, driven by a real git diff
• commit and push from the review, with the message editable before it runs
• composer-level model, thinking and access controls, plus a context dial wired to Pi's own usage and manual compaction
• composer autocomplete for Pi skills, prompt templates, and extension commands; skills are searchable as $skill or /skill, and the selected runtime adapter resolves the shorthand to its supported invocation form when sent
• @ file mentions in the composer, expanded to the file's workspace-relative path the way Pi reads it
• ! shell commands from the composer, run through the login shell with their output styled in the transcript
• prompt history that survives a restart, plus a search over it
• open the workspace in the user's own editor (Cmd/Ctrl+O) or terminal (Cmd/Ctrl+J), and the draft prompt in the editor (Cmd/Ctrl+E)
• a runtime per thread, with Pi as the default (Which runtime a thread gets)
• model picker with provider tabs, cross-provider search and favourites
• the branch in the thread's head is a menu: switch or create a branch, open, add or remove a worktree; "New thread" asks for the project first (the one in context selected, ↵ confirms), and the new thread's page offers project, machine ("Run on") and branch (its own worktree, its tau/… branch and the base) as pills under its heading
• enforced access levels: Tau's inline Pi extension gates workspace mutations and computer-control actions; read-only threads retain inspection tools, while ask-before-edits requires approval before clicks, typing, launches, shell commands, and file changes
• a Preview panel (/preview <url>, Cmd/Ctrl+Shift+B) showing a real browser view the host draws over the dock, and preview_open/navigate/status/snapshot/screenshot/click/type/press/scroll/evaluate/wait_for/resize/set_appearance/recording_start/recording_stop tools so the agent can read and drive the page it just changed; a floating picture of what an agent drives while the panel is hidden
• request_takeover for every runtime: when only the user can go on (a sign-in, a 2FA code, a captcha), a Your turn card above the composer brings the Preview, the driven app or a page in the user's own browser forward, offers to bring a signed-in session over from the user's browser, holds Computer Use, the Preview and evidence pictures, and Done hands control back
• built-in cross-platform computer use through @amaster.ai/pi-computer-use (Apache-2.0) and its bundled Cua Driver assets; safe mode excludes it, and an explicitly configured Pi package wins over Tau's bundled registration
• grouped command palette (Cmd/Ctrl+K) with arrow-key navigation, attributing every command to the extension that contributed it
• one settings page: workbench defaults, keybindings, and a click-through list of extensions rendered from the options each one declares
• Markdown rendering of messages: GFM tables, task lists, inline code, and syntax-highlighted code blocks with copy, all styled on the workbench palette; raw HTML is deliberately not enabled
• extension-provided tool renderers for reads, writes and shell commands
• thread title generation on a small model (the one the settings name, else one close to the thread's), automatic after the first prompt and manual on demand
• extension-free safe mode with empty layout slots collapsed

This page is docs/features.md in Tau's repository.