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

KeyRunner: Governed runtime securing AI agent API calls with credential injection & PII redaction. built by KeyRunner. Core capabilities include Pre-execution policy enforcement with RBAC before every API call, Runtime credential injection from external vaults without exposing secrets to agents, PII, PHI, and card data redaction from API responses before reaching the agent..

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.

KeyRunner differentiates with Pre-execution policy enforcement with RBAC before every API call, Runtime credential injection from external vaults without exposing secrets to agents, PII, PHI, and card data redaction from API responses before reaching the agent. 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.

KeyRunner is developed by KeyRunner. 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.

KeyRunner 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 Gateway. Review the feature comparison above to determine which fits your requirements.