HTTP MCP Header Secret Support - Implementation Summary

Use this reference for HTTP MCP header secret support in the copilot engine.

Problem Statement

When HTTP MCP headers include GitHub Actions secrets, mcp-config.json must:

1. Extract secrets from headers (e.g., ${{ secrets.DD_API_KEY }})
2. Declare those env variables in the execution step
3. Configure the MCP config's "env" section to passthrough those variables
4. Use the passed variables in the headers section

Example Workflow