Tau

About

Tau is Hugging Face's Python port of the Pi minimalist coding agent, published both as a usable terminal agent and as a reference for how coding agents are constructed. The package splits into tau_ai (a provider-neutral event stream over OpenAI, Anthropic, Codex, OpenRouter, HF, and OpenAI-compatible endpoints), tau_agent (the harness loop, tools, and durable JSONL sessions with resume and branching), and tau_coding (the Textual TUI, one-shot print mode, file/shell tools, skills, and AGENTS.md project instructions). Context accounting with manual and automatic compaction keeps long sessions coherent, and providers are configured through a catalog file rather than code. Because the 'brain' is decoupled from the interface, the project doubles as teaching material — the docs site walks through the architecture — and the README states the goal of showing how coding agents work. Developers who want a small, inspectable agent they can read and modify, rather than a maximalist product, are the audience.