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Burr

State machine framework for AI agent tracking

open sourceupdated Apr 21, 2026

Burr is an open-source Python framework for building applications as state machines with built-in observability and persistence. Designed for AI agents, chatbots, and RAG pipelines where tracking state transitions, debugging decisions, and replaying execution is critical. Features automatic state persistence, a visual UI for inspecting execution flows, time-travel debugging, and integration with LangChain, OpenAI, and any Python code. Apache 2.0 licensed by DAGWorks.

Burr models applications as state machines where actions transition between states based on conditions. This explicit structure makes agent behavior predictable, debuggable, and reproducible.

Automatic state persistence saves application state at every transition, enabling pause/resume, crash recovery, and human-in-the-loop workflows. Time-travel debugging replays past executions step by step.

The Burr UI provides visual inspection of execution flows, showing state transitions, action inputs/outputs, and decision points. This observability is invaluable for debugging complex agent behaviors.

Integrates with LangChain, OpenAI, and any Python code. Apache 2.0 licensed. Particularly valuable for teams building AI applications that need auditability and reproducibility.

Pricing

Free and open-source (Apache 2.0)

full pricing breakdown →

Platforms

Python, Web UI

Categories

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FAQ

What is Burr?

Burr is an open-source Python framework for building applications as state machines with built-in observability and persistence. Designed for AI agents, chatbots, and RAG pipelines where tracking state transitions, debugging decisions, and replaying execution is critical. Features automatic state persistence, a visual UI for inspecting execution flows, time-travel debugging, and integration with LangChain, OpenAI, and any Python code. Apache 2.0 licensed by DAGWorks.

Is Burr free?

Yes — Burr is open source and free to use. Free and open-source (Apache 2.0)

Is Burr open source?

Yes — Burr is open source.

What are the best Burr alternatives?

The top editor-verified Burr alternatives are Browser Use, Agno, Claude-Flow.