Pi

Pi is a minimal terminal coding harness designed to adapt to your workflows rather than forcing you into predefined patterns. Install via npm install -g @mariozechner/pi-coding-agent and extend it with TypeScript, custom providers, and bundled packages shared through npm or git.

Key capabilities include:

• Multi-provider support: Access 15+ providers including Anthropic, OpenAI, Google, Azure, Bedrock, Mistral, Groq, and more with hundreds of models. Switch models mid-session with /model or cycle through favorites with Ctrl+P.
• Tree-structured sessions: Navigate to any previous conversation point and branch from there. All branches live in a single file with filtering by message type and bookmark labels. Export to HTML or share via GitHub gist with /share.
• Context engineering: Load project instructions from AGENTS.md, customize system prompts via SYSTEM.md, and implement auto-compaction that summarizes older messages. Progressive disclosure through skills prevents prompt cache issues.
• Flexible interaction modes: Interactive TUI, print/JSON output for scripts, JSON RPC protocol for non-Node integrations, and SDK embedding for applications.
• Extensibility without bloat: Build features yourself using TypeScript extensions with access to tools, commands, keyboard shortcuts, and the full terminal UI. Install third-party packages or ask pi to build what you need.
• Message steering: Submit messages while the agent works—Enter sends steering messages that interrupt remaining tools, while Alt+Enter sends follow-ups that wait for completion.

Pi ships with powerful defaults but intentionally skips sub-agents, plan mode, and permission popups, letting you implement these your way through extensions or packages. The philosophy prioritizes a minimal core that you shape to fit your exact requirements.