Agen Shield vs Promptfoo MCP Proxy: Side-by-Side Comparison (2026)

Agen Shield: Endpoint & browser enforcement layer blocking dangerous AI agent actions pre-execution. built by Agen.co. Core capabilities include On-device pre-execution blocking of out-of-policy AI agent actions, Browser paste detection and blocking of sensitive data into AI tools, Unified policy plane shared across device, browser, and gateway enforcement..

Promptfoo MCP Proxy: Proxy layer for controlling and monitoring MCP server access in AI apps. built by Promptfoo. Core capabilities include MCP server whitelisting to block unapproved servers, Granular access control per user and application, Real-time monitoring of MCP interactions..

Both serve the Agentic AI Security market but differ in approach, feature depth, and target audience.

Agen Shield differentiates with On-device pre-execution blocking of out-of-policy AI agent actions, Browser paste detection and blocking of sensitive data into AI tools, Unified policy plane shared across device, browser, and gateway enforcement. Promptfoo MCP Proxy differentiates with MCP server whitelisting to block unapproved servers, Granular access control per user and application, Real-time monitoring of MCP interactions.

Agen Shield is developed by Agen.co. Promptfoo MCP Proxy is developed by Promptfoo. The vendor behind a product decides its roadmap, support, and longevity, so check each company's profile before you commit.

Agen Shield and Promptfoo MCP Proxy serve similar Agentic AI Security use cases: both are Agentic AI Security tools, both cover MCP Security, Agentic AI Security, AI Observability. Review the feature comparison above to determine which fits your requirements.