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Please reload this page . modelcontextprotocol / ext-apps Public * Notifications You must be signed in to change notification settings * Fork 377 * Star 2.8k * Code * Issues 124 * Pull requests 82 * Discussions * Actions * Projects * Security and quality 0 * Insights Additional navigation options * Code * Issues * Pull requests * Discussions * Actions * Projects * Security and quality * Insights Files Expand file tree main Breadcrumbs * ext-apps * / examples / system-monitor-server / Copy path Directory actions More options More options Directory actions More options More options Latest commit   History History History main Breadcrumbs * ext-apps * / examples / system-monitor-server / Copy path Top Folders and files Name Name Last commit message Last commit date parent directory .. src src     .gitignore .gitignore     README.md README.md     grid-cell.png grid-cell.png     main.ts main.ts     mcp-app.html mcp-app.html     package.json package.json     screenshot.png screenshot.png     server.ts server.ts     tsconfig.json tsconfig.json     tsconfig.server.json tsconfig.server.json     vite.config.ts vite.config.ts     View all files README.md Outline Example: System Monitor App A demo MCP App that displays real-time OS metrics with a stacked area chart for per-core CPU usage and a bar gauge for memory. MCP Client Configuration Add to your MCP client configuration (stdio transport): { "mcpServers" : { "system-monitor" : { "command" : " npx " , "args" : [ " -y " , " --silent " , " --registry=https://registry.npmjs.org/ " , " @modelcontextprotocol/server-system-monitor " , " --stdio " ] } } } Local Development To test local modifications, use this configuration (replace ~/code/ext-apps with your clone path): { "mcpServers" : { "system-monitor" : { "command" : " bash " , "args" : [ " -c " , " cd ~/code/ext-apps/examples/system-monitor-server && npm run build >&2 && node dist/index.js --stdio " ] } } } Features * Per-Core CPU Monitoring : Stacked area chart showing individual CPU core utilization over a 1-minute sliding window * Memory Usage : Horizontal bar gauge with color-coded thresholds (green/yellow/red) * System Info : Hostname, platform, and uptime display * Auto-Polling : Automatically starts monitoring on load with 2-second refresh interval * Theme Support : Adapts to light/dark mode preferences Running * Install dependencies: npm install * Build and start the server: npm run start:http # for Streamable HTTP transport # OR npm run start:stdio # for stdio transport * View using the basic-host example or another MCP Apps-compatible host. Architecture Server ( server.ts ) Exposes two tools demonstrating a polling pattern: * get-system-info (Model-visible) — Returns static system configuration: * Hostname, platform, architecture * CPU model and core count * Total memory * poll-system-stats (App-only, visibility: ["app"] ) — Returns dynamic metrics: * Per-core CPU timing data (idle/total counters) * Memory usage (used/free/percentage) * Uptime The Model-visible tool is linked to a UI resource via _meta.ui.resourceUri . App ( src/mcp-app.ts ) * Receives static system info via ontoolresult when the host sends the get-system-info result * Polls poll-system-stats every 2 seconds for dynamic metrics * Uses Chart.js for the stacked area chart visualization * Computes CPU usage percentages client-side from timing deltas * Maintains a 30-point history (1 minute at 2s intervals) Footer (c) 2026 GitHub, Inc. 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