Firefox DevTools MCP vs web-eval-agent

A side-by-side comparison of two Browser Automation servers — tools, transport, auth, maintenance, and copy-paste config for each.

	Firefox DevTools MCP Automate and inspect Firefox via WebDriver BiDi (Selenium) from any MCP client. Unverified stdio (local) No auth TypeScript	web-eval-agent Autonomous browser agent that evaluates and debugs your web app end-to-end from your IDE. Unverified stdio (local) API key Python
Category	Browser Automation	Browser Automation
Language	TypeScript	Python
Transport	stdio (local)	stdio (local)
Auth	None	API key
GitHub stars	228	1.2k
Last commit	4 days ago	4 months ago
Verified
Actively maintained
Install	`claude mcp add firefox-devtools npx @mozilla/firefox-devtools-mcp@latest`	`curl -LSf https://operative.sh/install.sh -o install.sh && bash install.sh && rm install.sh`
Repo	Open	Open

Verdict

Pick Firefox DevTools MCP if you want zero-setup with no API key, and you need the broadest set of tools.

Pick web-eval-agent if you prefer the more popular, battle-tested option.

Add Firefox DevTools MCP

Install / run

claude mcp add firefox-devtools npx @mozilla/firefox-devtools-mcp@latest

Paste into ~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "firefox-devtools-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@mozilla/firefox-devtools-mcp@latest",
        "--headless",
        "--viewport",
        "1280x720"
      ],
      "env": {
        "START_URL": "about:blank"
      }
    }
  }
}

Add web-eval-agent

Install / run

curl -LSf https://operative.sh/install.sh -o install.sh && bash install.sh && rm install.sh

Paste into ~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "web-eval-agent": {
      "command": "uvx",
      "args": [
        "--refresh-package",
        "webEvalAgent",
        "--from",
        "git+https://github.com/Operative-Sh/web-eval-agent.git",
        "webEvalAgent"
      ],
      "env": {
        "OPERATIVE_API_KEY": "<YOUR_KEY>"
      }
    }
  }
}

Requires `uv` (the Python package runner). Install it from https://docs.astral.sh/uv/ if `uvx` is not found.

FAQ

Firefox DevTools MCP or web-eval-agent — which is better?

Pick Firefox DevTools MCP if you want zero-setup with no API key, and you need the broadest set of tools. Pick web-eval-agent if you prefer the more popular, battle-tested option.

Can I use both Firefox DevTools MCP and web-eval-agent?

Yes — MCP clients let you enable multiple servers at once. Add both configs to your client's mcpServers and use whichever tool fits the task.

Do Firefox DevTools MCP and web-eval-agent work with Claude, Cursor and Windsurf?

Both do. Copy the per-client config below into Claude Desktop, Cursor, or Windsurf.

View Firefox DevTools MCP →View web-eval-agent →More comparisons →