http-mcp-headers

# 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., `${{ secrets.DD_API_KEY }}`) 2. Declare those env variables in the execution step 3. Configure the MCP config's "env" section to passthrough those variables 4. Use the passed variables in the headers section ## Example Workflow ```markdown on: workflow_dispatch: permissions: contents: read engine: copilot mcp-servers: datadog: type: http url: "https://mcp.datadoghq.com/api/unstable/mcp-server/mcp" headers: DD_API_KEY: "${{ secrets.DD_API_KEY }}" DD_APPLICATION_KEY: "${{ secrets.DD_APPLICATION_KEY }}" DD_SITE: "${{ secrets.DD_SITE || 'datadoghq.com' }}" allowed: - search_datadog_dashboards - search_datadog_slos - search_datadog_metrics - get_datadog_metric # Datadog Dashboard Search Search for Datadog dashboards and provide a summary. ``` ## Generated Output ### 1. MCP Config (mcp-config.json) ```json { "mcpServers": { "datadog": { "type": "http", "url": "https://mcp.datadoghq.com/api/unstable/mcp-server/mcp", "headers": { "DD_API_KEY": "${DD_API_KEY}", "DD_APPLICATION_KEY": "${DD_APPLICATION_KEY}", "DD_SITE": "${DD_SITE}" }, "tools": [ "search_datadog_dashboards", ...