Documentation

Build with Phoson

The open-source agent engine and terminal CLI — framework-free, multi-provider, and built to be extended.

Open Source RuntimeMIT Licenseon PyPI

phoson-engine-minimal

Framework-free Python runtime for autonomous agents. Custom ReAct loop built directly on provider SDKs — multi-provider, typed events, branchable sessions, cost tracking, and an interactive CLI.

Framework-freeMulti-providerTyped eventsBranchable sessionsMIT

What you can build

Streaming AI

Real-time token-by-token responses with a typed event stream

Branchable Sessions

Rewind and branch conversations with ConversationTree

Tools & MCP

@tool decorator and MCP servers with pooled sessions

Multi-Provider

OpenAI, Anthropic, Gemini, OpenRouter, Ollama and more