Sage

Sage is a lightweight security tool designed to protect AI coding assistants from executing harmful actions. It intercepts tool calls—shell commands, URL requests, and file operations—before they run, analyzing them against multiple threat detection layers to catch malicious activity.

The system detects dangerous commands like reverse shells and privilege escalation, identifies malicious URLs through cloud reputation checks, prevents credential leaks, and guards against supply-chain attacks on packages. It integrates directly into platforms like Claude Code, Cursor, and VS Code with minimal setup. The maker says it was built with Claude Code.