Pi Agent

Pi Agent

Pi Agent is a minimal, terminal-based coding agent built around the idea that the harness should adapt to the developer instead of forcing the developer to adapt to the harness. Hosted at https://pi.dev/ and shipped by Earendil Inc., Pi Agent runs as a TUI in the terminal, exposes a tree-structured session history, supports skills, AGENTS.md and SYSTEM.md context files, and is unusually token-efficient thanks to a minimal default system prompt. The product's tagline is "There are many agent harnesses, but this one is yours."

Pi Agent ships in four runtime modes. Interactive mode delivers the full terminal UI with rich keyboard shortcuts and a stylable interface. Print mode runs Pi Agent headlessly with a single query for use inside shell scripts. JSON mode streams structured events from a Pi Agent run for piping into other tools. RPC mode exposes Pi Agent over JSON over stdin/stdout so non-Node processes can drive it. An SDK lets developers embed Pi Agent directly into their own applications. The product documentation points to OpenClaw as a real-world example of that SDK being used.

The model layer is provider-agnostic. Pi Agent works with Anthropic, OpenAI, Google, Azure, Bedrock, Mistral, Groq, Cerebras, xAI, Hugging Face, Kimi For Coding, MiniMax, NVIDIA, OpenRouter, Ollama and more than fifteen other providers in total. Authentication can be done with API keys or OAuth. The /model command and Ctrl+L shortcut switch models mid-session, while Ctrl+P cycles through favourites. Custom providers and models can be added through a models.json file or extensions.

Context engineering is central to Pi Agent. The platform loads AGENTS.md project instructions from ~/.pi/agent, parent directories and the current directory, supports per-project SYSTEM.md overrides, auto-summarises older messages via compaction, and ships a skills system for capability packages loaded on demand. Prompt templates let developers reuse common prompts as Markdown files. Extensions, written in TypeScript, can inject context before each turn, filter message history, implement RAG or build long-term memory. Sessions can be branched, shared, exported to HTML, or pushed to a GitHub gist with /share to obtain a shareable URL.

Pi Agent is built for developers who want to customise their coding workflow rather than accept whatever defaults a closed product provides.