Firefox DevTools MCP
by Mozilla
Official listing: built and published by Mozilla. More from Mozilla
Lets MCP clients automate and debug a local Firefox via WebDriver BiDi: navigate pages, fill forms, inspect network and console, and take screenshots.
Use it now
Keep it with up to 9 other tools you're setting up, then share them all as one link.
Try this first
Ask your assistant, with Firefox DevTools MCP connected:
- Page Management
Use Firefox DevTools MCP to list Firefox tabs: ‹what you need›
- Snapshot And Input
Use Firefox DevTools MCP to take a DOM snapshot: ‹what you need›
- Network And Console
Use Firefox DevTools MCP to capture network requests and console messages for inspection: ‹what you need›
Connect it over MCP
{
"mcpServers": {
"firefox-devtools-mcp": {
"command": "npx",
"args": [
"-y",
"@mozilla/firefox-devtools-mcp@latest",
"--headless",
"--viewport",
"1280x720"
]
}
}
}claude mcp add firefox-devtools-mcp -- npx -y @mozilla/firefox-devtools-mcp@latest --headless --viewport 1280x720
It runs on your computer, so web assistants such as Grok and ChatGPT can’t start it.
Setup guide: github.com/mozilla/firefox-devtools-mcp
Install the CLI
Install it as its own instructions say.
Setup guide: github.com/mozilla/firefox-devtools-mcp
Compare
Press Compare to add it to the tray at the bottom of the window, then pick up to 2 others anywhere on the site.
- Access
- MCPCLI
- Auth
- None
- Skills
- 4
Skills
Page Management
Lists, selects, and navigates Firefox tabs with list_pages, select_page, and navigate_page, including headless runs and Firefox for Android.
Snapshot And Input
Takes a DOM snapshot with element UIDs, then clicks or fills elements by UID with click_by_uid and fill_by_uid to drive forms.
Network And Console
Captures network requests and console messages for inspection with list_network_requests, get_network_request, and list_console_messages.
Screenshots And Downloads
Captures page screenshots with screenshot_page and tracks or configures file downloads with list_downloads and set_download_behavior.
