I built javaperf – an MCP (Model Context Protocol) server that lets AI assistants profile Java applications without touching the command line.
If you’ve ever debugged Java performance issues, you know the drill: jps, jcmd, jfr… memorizing flags, parsing output. What if your AI assistant could do this for you?
What is MCP?
Model Context Protocol (MCP) is a standard for connecting AI assistants to external tools. Instead of AI just generating code suggestions, it can actually:
- Run diagnostics on your running Java apps
- Analyze thread dumps
- Inspect JFR recordings
- All through natural conversation
javaperf Features
-
Process Discovery: Auto-detect running Java processes via
jps -
Thread Analysis: Dump and analyze threads (
jcmd Thread.print) - VM Flags: Inspect JVM configuration
- JFR Support: Record and analyze Java Flight Recorder data
- Performance Counters: Access low-level JVM metrics
Installation
npm install -g javaperf
Or use directly via npx (no install needed):
npx javaperf
Connecting to Claude Desktop
Add to your claude_desktop_config.json:
{
"mcpServers": {
"javaperf": {
"command": "npx",
"args": ["-y", "javaperf"]
}
}
}
Example Usage
Once connected, you can ask Claude things like:
- “Show me all running Java processes”
- “Analyze thread dump for process 1234”
- “Start a 60-second JFR recording”
- “Why is my app using so much memory?”
The AI handles the jcmd, jfr, and jps commands behind the scenes.
Why This Matters
Before MCP: You Google the right flags, copy-paste commands, manually parse output.
After MCP: “Hey Claude, why is my Spring Boot app slow?” → AI investigates → Finds thread contention → Suggests fixes.
Links
- GitHub: https://github.com/theSharque/mcp-jperf
- npm: https://www.npmjs.com/package/javaperf
- Requirements: Node.js 18+, JDK 8u262+ or 11+
Try It Out
If you’re working with Java and using Claude Desktop or Cursor IDE, give it a spin. Would love feedback on what other profiling features would be useful!
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