Crowd Test

The mob, on tap — an MCP server for crowd-test.

Ask Claude Desktop, Claude Code, Cursor, or any MCP client to unleash a crowd of AI virtual users — impatient shoppers, confused seniors, keyboard-only users, chaos monkeys — on your website. They browse it in real Chromium, file findings, and hand back a damage report with a survival grade (S–F).

"Send the mob at https://staging.myapp.com and tell me what to fix first."

That's the whole workflow now.

Install

pip install crowd-test-mcp

An LLM key is required in the server's environment: ANTHROPIC_API_KEY or OPENAI_API_KEY.

Claude Code

claude mcp add crowd-test -e ANTHROPIC_API_KEY=sk-... -- crowd-test-mcp

Claude Desktop / Cursor / anything MCP

{
  "mcpServers": {
    "crowd-test": {
      "command": "crowd-test-mcp",
      "env": { "ANTHROPIC_API_KEY": "sk-..." }
    }
  }
}

Tools

Tool	What it does
run_crowd_test	Send the crowd at a URL. Pick personas, add a random mob, set a goal, choose the verification depth (none / detective / cross / tribunal). Returns a compact damage summary; full markdown/HTML reports land in ~/crowd-test-reports/.
list_personas	The ten built-in ringleaders and what each one catches.
preview_mob	Preview the random mob a given count/seed would generate.
read_report	Fetch the newest full markdown report from disk.

The verification tribunal

Findings can be cross-examined by up to three independent harnesses before they count against the grade — a skeptical detective agent, a raw Playwright probe, and a Microsoft Webwright agent. Automation artifacts get disputed instead of panicking you. Details in the crowd-test README.

Deeper layers need one-time extras:

pip install crowd-test[probe] && playwright install chromium   # verify="cross"
pip install git+https://github.com/microsoft/Webwright         # verify="tribunal"

Good to know

• Runs take minutes, not seconds — every persona drives a real browser. Start with 2–3 personas; escalate to mob=10 when you mean it.
• Only test what you own. The mob is for your own staging and production sites, not other people's.
• Reports default to ~/crowd-test-reports/<host>-<timestamp>/.

License

MIT