Spec Driven Development
by formulahendry
MCP Server that facilitates spec-driven development workflows, not just Vibe Coding.
Runs on your computer★ 440MITUpdated 14 months ago
Install
Zen DevTools MCP
Overview
Description from the maker (original English)
Attach firefox-devtools-mcp to your running Zen or Firefox, auto-restarting with Marionette.
PopNx MCP’s three pillars
These three are never merged into one score: opinions, measurements and popularity are different things.
- User voiceiNo reviews yetReviews open together with accounts in a later step
- Our basic checksi1 of 1 passedChecked from public information; code not scanned yet
- UsageiNot measured yet★ –
What you can do with it
We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.
- Connection: –
- Transport:
- Category: Other
Install
Pick the AI app you use, then copy the settings.
Before you install
- Basic checks: 1 of 1 passed
- Runs on your computer with your user’s permissions (files, network, apps).
- The registry lists no key to fill in.
The maker has not listed install details in the registry. See the maker’s README below.
What it can do
Runs on your computer; the tool list appears in your AI app after you install it.
Basic checksi
We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 7, 2026
- ✓ Pass
Maker matches the repo
The registry name was verified with the GitHub account sushruth, which owns the repo
- … Not checked yet
Still maintained
We have not read this repo from GitHub yet
- … Not checked yet
Has a licence
We have not read this repo from GitHub yet
- – Not applicable
Endpoint responds
This one runs on your computer; there is no internet endpoint
- – Not applicable
Sign-in with OAuth
Runs on your computer and uses local settings instead
- … Not checked yet
No hidden instructions in tool descriptions
Runs on your computer; we can only read tool lists from internet endpoints
Compared with others in Otheri
- More stars than 0% of the other 32572 servers in this category
- Published to the registry more recently than 70% of the other 32572 servers in this category
- Basic checks equal to or better than 100% of the other 32572 servers in this category
Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.
Common questions
Is Zen DevTools MCP safe?
It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.
What keys or codes does it need?
The registry does not list a required key, though some servers ask you to sign in on first use.
Does it run on my computer or in the cloud?
It runs on your computer. Your AI app starts it when needed, and data does not pass through the maker’s servers (unless it calls an online service itself).
Is it still maintained?
The GitHub repo last changed –, and the latest version (1.0.0) reached the registry 16 days ago.
Which apps can use it?
Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code.
What can I use instead?
In the same category: Spec Driven Development, Remote Desktop Commander, AvaHR
Alternatives
Servers in the same category from other makers, sorted by stars.
Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi
Remote Desktop Commander
by desktop-commander
Remote Desktop Commander: use files, terminal and processes on your own computers from any AI app.
Runs in the cloud★ 211Updated yesterday
Install
AvaHR
by avahr.com
Read hiring data and create inactive assessment and questionnaire drafts for human review.
Runs in the cloudUpdated today
Install
README from the maker
Open the README
Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.
zen-devtools-mcp
Wraps @mozilla/firefox-devtools-mcp so it attaches to your already-running Firefox-based browser — Zen Browser, Firefox, or any fork — instead of launching a throwaway instance.
The upstream --connectExisting mode requires the browser to have been launched with Marionette enabled. Plain relaunches (clicking the dock icon, open -a Zen) don't set that, so attaching fails. This wrapper fixes that: if Marionette isn't up, it gracefully quits the browser (session restore keeps your tabs), relaunches it with --marionette, waits for the port, then starts the MCP.
Install / run
No install needed — run it straight from GitHub:
npx github:sushruth/zen-devtools-mcpbunx github:sushruth/zen-devtools-mcp
Options
| Flag | Default | What it controls |
|---|---|---|
--app | Zen | macOS app name for open -a / quit |
--process | zen | process name for pgrep -x |
--port | 2828 | Marionette port to probe and listen on |
Examples:
# Firefox instead of Zennpx github:sushruth/zen-devtools-mcp --app Firefox --process firefox
Zen with a custom Marionette port
npx github:sushruth/zen-devtools-mcp --port 2829
MCP client config
OpenCode example:
"zen-devtools": {"type": "local", "command": ["npx", "-y", "github:sushruth/zen-devtools-mcp"], "enabled": true }, "firefox-devtools": { "type": "local", "command": ["npx", "-y", "github:sushruth/zen-devtools-mcp", "--app", "Firefox", "--process", "firefox", "--port", "2829"], "enabled": true }
Claude Code (claude mcp add-json zen-devtools ' ' or .mcp.json):
"zen-devtools": {"command": "npx", "args": ["-y", "github:sushruth/zen-devtools-mcp"] }
Notes
- Session restore preserves tabs across wrapper-triggered restarts.
- Marionette can't be enabled on a live browser process — a restart is unavoidable the first time.
- macOS-only (
open,osascript,pgrep). - Passes
--connectExisting --enableScriptto the underlying MCP; it inherits stdio from its parent.