Show HN: Kairos – Open-source risk and fraud decisioning platform

Kairos is an open-source, real-time fraud and risk decisioning platform that automatically approves, flags, or blocks transactions as they occur while recording the reasoning behind each decision. It differentiates itself from competitors like Sardine and Sift by offering AI agent tuning through Claude Code and an MCP server, plus decision models that can detect fraud with minimal labeled data. The platform provides SDKs for TypeScript and Python, traditional ML models (logistic regression and XGBoost), and self-hosting capabilities via Docker.