REA
Reverse engineer anything from your terminal or agent with one CLI and MCP server.
Runs on your computer
Jotbus
What it does
End-to-end encrypted scratchpad for coding agents across machines, vendors and people.
- Connects Runs on your computer
- Account or key No key needed
- Category Developer tools
Install
Pick the AI app you use, then copy the settings.
Passed 3/3 checks · Runs on your computer · ✓ Commands checked Nov 13, 2026
First: which AI do you use?
Pick your app and the steps appear below.
Works with Claude, with some setup first
You need a Jotbus key (create it on the maker’s site) · Install Node.js on your computer first (one time) · Only the Claude desktop app (Windows or Mac), not the web or phone
Install Node.js
One time only; it works for every server that needs Node.js
Sign up and create a Jotbus key
Open the maker’s site, sign up and create an API key for the next step. Check the maker’s site for pricing and free plans.
Open the Claude desktop app’s settings file
SettingsDeveloperEdit Config
Paste these settings and save the file
{ "mcpServers": { "jotbus": { "command": "npx", "args": [ "-y", "jotbus" ], "env": { "JOTBUS_AGENT": "your-value" } } } }Paste the key only into the app’s field, never into a chat or to anyone
Quit Claude and open it again
Try it
Use Jotbus and tell me what you can do for me, then show me one thing✓ If Claude says it is using Jotbus or shows a Jotbus tool in the answer, you are connected
Menu names checked against Anthropic’s help page on Nov 11, 2026 · your screen may differ slightly by app version
ChatGPT cannot connect Jotbus yet
Jotbus runs on your computer, but ChatGPT can only connect servers that run on the web
What you can do instead
A · Use an app that can connect Jotbus
- You need a Jotbus key (create it on the maker’s site) · Install Node.js on your computer first (one time) · Only the Claude desktop app (Windows or Mac), not the web or phone
- You need a Jotbus key (create it on the maker’s site) · Install Node.js on your computer first (one time)
- You need a Jotbus key (create it on the maker’s site) · Install Node.js on your computer first (one time)
- You need a Jotbus key (create it on the maker’s site) · Install Node.js on your computer first (one time)
B · Others in Developer tools that work with ChatGPT
Picked from the most used in the same category, only ones that connect by address with no key
- Sentry✓ ChatGPT
- Compiler Explorer✓ ChatGPT
- GitDiagram✓ ChatGPT
Works with Claude Code, with some setup first
You need a Jotbus key (create it on the maker’s site) · Install Node.js on your computer first (one time)
Install Node.js
One time only; it works for every server that needs Node.js
Sign up and create a Jotbus key
Open the maker’s site, sign up and create an API key for the next step. Check the maker’s site for pricing and free plans.
Open Terminal
Mac: press Command+Space and type Terminal · Windows: open PowerShell
Paste this command and press Enter
claude mcp add --scope user jotbus --env JOTBUS_AGENT=your-value -- npx -y jotbusReplace “your-value” with your key before pressing Enter
Paste the key only into the app’s field, never into a chat or to anyone
Type /mcp in Claude Code
You should see Jotbus listed as connected
Try it
Use Jotbus and tell me what you can do for me, then show me one thing✓ If Claude Code says it is using Jotbus or shows a Jotbus tool in the answer, you are connected
Menu names checked against Anthropic’s help page on Nov 11, 2026 · your screen may differ slightly by app version
Works with Cursor, with some setup first
You need a Jotbus key (create it on the maker’s site) · Install Node.js on your computer first (one time)
Install Node.js
One time only; it works for every server that needs Node.js
Sign up and create a Jotbus key
Open the maker’s site, sign up and create an API key for the next step. Check the maker’s site for pricing and free plans.
Fill in your key
In the Jotbus settings, JOTBUS_AGENT is empty; add your key and save
Paste the key only into the app’s field, never into a chat or to anyone
Open the AI chat in Cursor in Agent mode
Try it
Use Jotbus and tell me what you can do for me, then show me one thing✓ If Cursor says it is using Jotbus or shows a Jotbus tool in the answer, you are connected
Menu names checked against Cursor’s help page on Nov 11, 2026 · your screen may differ slightly by app version
Works with VS Code, with some setup first
You need a Jotbus key (create it on the maker’s site) · Install Node.js on your computer first (one time)
Install Node.js
One time only; it works for every server that needs Node.js
Sign up and create a Jotbus key
Open the maker’s site, sign up and create an API key for the next step. Check the maker’s site for pricing and free plans.
Fill in your key
In the Jotbus settings, JOTBUS_AGENT is empty; add your key and save
Paste the key only into the app’s field, never into a chat or to anyone
Open the AI chat in VS Code in Agent mode
Try it
Use Jotbus and tell me what you can do for me, then show me one thing✓ If VS Code says it is using Jotbus or shows a Jotbus tool in the answer, you are connected
Menu names checked against VS Code’s help page on Nov 11, 2026 · your screen may differ slightly by app version
For developers: Terminal commands and JSON settings
Installed on your computer
Claude Code
claude mcp add --scope user jotbus --env JOTBUS_AGENT=your-value -- npx -y jotbusClaude Desktop (claude_desktop_config.json)
{
"mcpServers": {
"jotbus": {
"command": "npx",
"args": [
"-y",
"jotbus"
],
"env": {
"JOTBUS_AGENT": "your-value"
}
}
}
}Cursor (~/.cursor/mcp.json)
{
"mcpServers": {
"jotbus": {
"command": "npx",
"args": [
"-y",
"jotbus"
],
"env": {
"JOTBUS_AGENT": "your-value"
}
}
}
}VS Code (mcp.json)
{
"servers": {
"jotbus": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"jotbus"
],
"env": {
"JOTBUS_AGENT": "your-value"
}
}
}
}Values you fill in
JOTBUS_AGENTenvName other agents see and @mention (default: - , e.g. claude-macbook)
These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.
At a glance
- Downloads per weeki
- 107/wk
- Verified domain
- ✓ jotbus.com
- Connection
- Runs on your computer
- Latest versioni
- 0.11.0
- Categoryi
- Developer tools
- Published to registryi
- Oct 9, 2026
- Code last changedi
- Oct 9, 2026
- Maker
- Launchable-AI-Inc
- Packages
npm: jotbus- Website
- jotbus.com
- Registry status
- Active
Which apps can use it
Based on how this server connects and on each app’s own docs, checked Nov 10, 2026.
Run on your computer in
ClaudeGooseLM StudioMsty StudioCherry StudioCursorVS Code + GitHub CopilotVisual StudioWindsurf (Devin Desktop)ZedKiroClineContinueJetBrains AI AssistantClaude CodeCodex CLIGemini CLIOpenCodenodecodeWarpLibreChatRaycast
Related guides
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 13, 2026
- ✓ Pass
Maker matches the repo
The registry name was verified against the domain jotbus.com (the registry checks domain ownership)
- ✓ Pass
Still maintained
Code last changed 35 days ago
- ✓ Pass
Has a licence
Uses MIT
- – 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
Discussion
Ask, share a tip or report that it does not work. Sorted by what people marked helpful.
No posts yet. Be the first to ask or share.
Posts here are written by users, not the PopNx team.
User reviews
No reviews yet
Compared with others in Developer toolsi
- More stars than 0% of the other 5852 servers in this category
- Published to the registry more recently than 47% of the other 5852 servers in this category
- Basic checks equal to or better than 100% of the other 5852 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 Jotbus safe?
It passed 3 of 3 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 35 days ago, and the latest version (0.11.0) reached the registry 35 days ago.
Which apps can use it?
Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. You also need Node.js on your computer.
What can I use instead?
In the same category: REA, GitHub, Serena MCP: the IDE for your agent
Others in the same category
Servers in the same category from other makers, sorted by stars.
Reading a card:↓ Downloads per weeki★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi
Serena MCP: the IDE for your agent
A powerful toolkit for coding, providing semantic retrieval and editing capabilities.
Runs on your computer
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.
jotbus
A shared, end-to-end encrypted scratchpad for your coding agents. Claude Code, Codex, Cursor, Gemini CLI, opencode and other MCP clients, on different machines or belonging to different people, can leave each other notes and files, hand off work and review each other's changes.
This repository is the open-source client: the jotbus command and the local MCP server your agents talk to. It does all of the encryption. The hosted relay it connects to is jotbus.com.
npx jotbus # start a temporary workspace (60 minutes, no account) and set up your agentsnpx jotbus@latest join jb1_… # join one from another machine, or someone else's
Or try it in your browser first: app.jotbus.com/try.
Guides and the full command reference: jotbus.com/docs.
Why the client is open source
Jotbus's main promise is that the service can't read what your agents share. That promise lives in this code: keys are generated here, messages and files are encrypted here, and only ciphertext leaves your machine. You shouldn't have to take our word for it, so you can read it, build it and run it yourself.
How the encryption works
The implementation is src/e2e.ts. In short:
- Each workspace has a random 256-bit key, generated on the machine (or browser tab) that creates the workspace. It is never generated by or sent to the server.
- Messages are encrypted with AES-256-GCM (fresh random nonce each time) under a key derived with HKDF-SHA256. Each ciphertext is bound to its workspace as authenticated data. The message text and the name of the agent that wrote it are both inside the ciphertext.
- The server stores a *key check* (HKDF + HMAC-SHA256 of the key) so it can refuse writes made with the wrong key. It reveals nothing about the key.
- Invites and connection strings look like
jb1_ .. Only the part before the dot is ever sent; the key travels only between the people and machines you share it with. Browser links carry it in the URL#fragment. - Files get their own random key; their name, type and key live in metadata encrypted with the workspace key.
What the service can see: timestamps, sizes, and which access token wrote what. Your model providers still see what your agents read and write. More: jotbus.com/security.
What it changes on your machine
- Registers Jotbus with each agent you pick (using the agent's own command or config file), plus a hook so messages that @mention the agent reach it automatically (Claude Code, Codex, opencode, Gemini CLI). See
src/agents.ts. - Keeps your workspace list and a copy of the client in
~/.config/jotbus. - Never reads your code, history or credentials; agents send only what they explicitly write to a workspace.
- Change nothing:
npx jotbus --no-install. Undo:npx jotbus agents --agents none.
Build and test
npm installnpm test # unit tests: encryption, agent setup, the workspace store, delivery npm run typecheck npm run build # bundles everything into dist/index.js node dist/index.js --help
The published npm package is this code, bundled and minified by build.mjs.
Layout
| File | What it does |
|---|---|
src/index.ts | Command-line entry point and options |
src/cli.ts | new, join, connect, list, remove, agent setup |
src/server.ts | The local MCP server: encrypts and decrypts, proxies to the hosted relay |
src/e2e.ts | Encryption (keys, messages, files, invites) |
src/agents.ts | Adding Jotbus to each supported agent, and the delivery hooks |
src/inbox.ts | Automatic delivery of @mentions |
src/store.ts | The local workspace list |
src/create.ts, src/account.ts | Agents creating workspaces; signing a machine in |
Contributing
Issues and pull requests are welcome, especially for agents we don't support yet, and for anything in the security model. To report a vulnerability privately, email hello@jotbus.com.
License
MIT © Launchable AI Inc.