AegisGate

Open-source security gateway for LLM APIs — prompt injection detection, PII redaction, dangerous response sanitization, and audit logging. OpenAI/Claude compatible, MCP & Agent SKILL support. Drop-in proxy for AI coding agents (Cursor, Claude Code, Codex). Maintained by ax128 on GitHub, where it has earned 50 stars from the community.

It's actively developed around ai-agent, ai-gateway, api-security, and is a solid reference for anyone building with these tools.