pi-subagents

Pi is an open-source AI agent harness and toolkit from earendil-works for building and running coding agents. Its packages provide a unified multi-provider LLM API, an agent runtime with tool calling and state management, an interactive coding-agent CLI, a terminal UI library with differential rendering, and vendor-neutral telemetry contracts and adapters. Slack and chat automation are provided through a separate package project. Pi does not provide built-in restrictions for filesystem, process, network, or credential access; it runs with the permissions of its launching user and process. The project documents containerization and sandboxing approaches, including a local Linux micro-VM, Docker, and policy-controlled sandboxing, for stronger isolation.

Pi Web is an open-source local browser interface for the Pi coding agent, developed in the agegr/pi-web repository. It uses Pi’s local configuration and session files, allowing users to browse, resume, rename, export, delete, and branch project-grouped conversations; run agent turns; and inspect running state, context usage, costs, and compaction details. New sessions create independent session files, while “Edit from here” creates a branch within the current session. Its project workspace supports file browsing and uploads, Git diff inspection, automatic previews for source files, Markdown, images, audio, PDFs, and DOCX files, and Git worktree switching. Configuration panels manage provider logins and API keys, models and model tests, plugin packages, and skills. The interface supports English, Simplified Chinese, and Traditional Chinese, follows the browser language initially, and includes a language switcher. Pi Web is distributed through the `@agegr/pi-web` npm package, requires Node.js 22.19.0 or newer, and listens on `127.0.0.1` by default. Remote binding and HTTP Basic Authentication are available, but the documentation warns that Basic Auth does not encrypt credentials in transit and that the service should not be exposed over plain HTTP without a trusted reverse proxy or VPN. It reads Pi agent data from `~/.pi/agent` by default, shares Pi’s model, settings, and credential storage, and limits file browsing to known project or session roots rather than providing general filesystem access.

PI-Desktop is a local-first desktop workspace for AI coding agents, built with Electron, a Rust host core, and the pi Agent Harness. It lets users open local projects, connect cloud or local models through providers such as OpenAI-compatible APIs, manage projects and long-running sessions, and review file changes and command output. Its architecture separates the React renderer, Electron desktop orchestration, Rust-managed permissions, filesystem access, SQLite persistence and secrets, and a pi Agent sidecar responsible for the agent loop, model interaction, and streaming. Agent, Plan, and Goal modes provide different approval boundaries; agents can read and edit files, run commands, and delegate exploration, implementation, research, testing, or review to background Subagents. The workspace supports MCP servers, Skills, installable Plugins, model and provider switching, session imports, notifications, context checkpoints, and a plugin marketplace. Conversations are stored locally as JSONL with a SQLite index, settings and logs remain on the machine, credentials use the operating-system keychain, and model requests go directly to the configured provider or endpoint. Plugin processes are permission-gated and isolated from the renderer, but plugins remain user-trusted code rather than a complete operating-system sandbox. It is an early-preview cross-platform application distributed for macOS, Windows, and Linux under the GNU Lesser General Public License v3.0.

pi-peer is a pi extension for discovering and messaging coding-agent sessions. It provides `list_peers` to show sessions, working directories, and statuses, and `message_peer` to send short plain-text messages to a named session. Messages carry no conversation history or files and arrive marked as peer text with no authority: they cannot approve actions, change configuration, or execute slash commands. Local messages use disk-backed mailboxes that survive restarts and queue mail for inactive sessions; sessions can also communicate across team machines through a shared Redis server. The extension supports inbound-message policies and stores local peer data with restricted filesystem permissions.