Show HN: Sentinel Gate – Open-source RBAC firewall for MCP agents (github.com)

Sentinel Gate has been introduced as an open-source role-based access control (RBAC) firewall specifically designed for Model Context Protocol (MCP) agents. This tool acts as a proxy between AI agents, such as Claude and GPT, and MCP tools, providing crucial functionalities like authentication, access control, rate limiting, and comprehensive audit logging. By implementing policy enforcement via Common Expression Language (CEL) rules, Sentinel Gate allows users to dictate what operations AI agents can perform, such as restricting deletion actions for non-admin users or allowing read-only file access from designated directories. The significance of Sentinel Gate lies in its ability to enhance security and control over AI operations, which is increasingly vital as AI agents gain capabilities like querying databases and executing code. With features like deterministic decision-making and a structured audit trail, it ensures transparency and compliance in AI-driven environments. Moreover, the ease of integration, via Docker or direct installation, along with its zero-dependency nature, positions Sentinel Gate as a practical solution for organizations looking to mitigate risks associated with automated AI actions while maintaining flexibility in policy management. This development could have far-reaching implications for best practices in AI governance and operational security.