BROWSER AUTOMATION / Mozilla
Firefox DevTools MCP
Automate and inspect a local Firefox browser through WebDriver BiDi and selectable tool presets.
“Automate and inspect a local Firefox browser through WebDriver BiDi and selectable tool presets.”
01 / THE REASONING
Why this made the selection.
- Automate and inspect a local Firefox browser through WebDriver BiDi and selectable tool presets.
- The setup documentation makes this operating boundary explicit: Browser tools act on reachable pages and browser session state. Broader developer presets add script, network and debugging access.
02 / THE REVIEW RECORD
What we actually inspected.
Source review has boundaries.
A clear record is more useful than a “safe” badge.
Material inspected
- README.md
- LICENSE-MIT
- package.json
- src/cli.ts
Our findings
- Browser tools act on reachable pages and browser session state. Broader developer presets add script, network and debugging access.
- The basic preset includes evaluate_script; internal Mozilla-only modules are omitted from the public package even if requested. Android mode wipes the target app data before each session.
Not established by this review
- No server installation, authentication, live tool execution or isolation test was performed.
- Package/container parity with the pinned source and transitive dependency security were not established.
The review applies to the material and revision named here. A newer upstream release can change its behavior.
03 / PUT IT TO WORK
Connect a server deliberately.
DOCUMENTED COMMAND
npx @mozilla/firefox-devtools-mcp@latestCopying does not execute this command. It may retrieve a newer version than the reviewed source.
- Run the local package with Node.js >=20.19.0 and Firefox installed; use a dedicated profile and --tool-preset slim when script evaluation is not needed.
- Verify the connected account, available tools and target resource before authorizing mutations.
Before you start
- Pinned package Node.js requirement: >=20.19.0.
- A compatible local process MCP client.
- Browser tools act on reachable pages and browser session state. Broader developer presets add script, network and debugging access.
04 / FOLLOW THE EVIDENCE
The source trail.
Our notes are separate from the original resource.
Check upstream before adopting a new version.
https://github.com/mozilla/firefox-devtools-mcp/blob/dff834a995bc5e4853c03103e0b83310e7a57a11/README.md
Supports: description, setup, capabilities, review, limitations
https://github.com/mozilla/firefox-devtools-mcp/blob/dff834a995bc5e4853c03103e0b83310e7a57a11/LICENSE-MIT
Supports: license
- Pinned package metadata ↗Checked
https://github.com/mozilla/firefox-devtools-mcp/blob/dff834a995bc5e4853c03103e0b83310e7a57a11/package.json
Supports: install, language, review
https://github.com/mozilla/firefox-devtools-mcp/blob/dff834a995bc5e4853c03103e0b83310e7a57a11/src/cli.ts
Supports: review, install, access, limitations