Show HN: AgentFuse – A local circuit breaker to prevent $500 OpenAI bills

Hey HN, I’ve been building agents recently, and I hit a problem: I fell asleep while a script was running, and my agent got stuck in a loop. I woke up to a drained OpenAI credit balance. I looked for a tool to prevent this, but most solutions were heavy enterprise proxies or cloud dashboards. I just wanted a simple "fuse" that runs on my laptop and stops the bleeding before it hits the API. So I built AgentFuse. It is a lightweight, local library that acts as a circuit breaker for LLM calls. Drop-in Shim: It wraps the openai client (and supports LangChain) so you don't have to rewrite your agent logic. Local State: It uses SQLite in WAL mode to track spend across multiple concurrent agents/terminal tabs. Hard Limits: It enforces a daily budget (e.g., stops execution at $5.00). It’s open source and available on PyPI (pip install agent-fuse). I’d love feedback on the implementation, specifically the SQLite concurrency logic! I tried to make it as robust as possible without needing a separate server process.