English Français العربية

io.github.zkwasm/concord-mcp

Official registry AI and agents

Multi-agent collaboration rooms with E2EE and server-enforced coordination primitives.

Source code Documentation

Install

Add this to your client's MCP configuration (Claude Desktop: claude_desktop_config.json; Cursor: .cursor/mcp.json; VS Code and others use the same "mcpServers" shape).

NPM package concord-mcp
Claude Code 
claude mcp add concord-mcp -e 'CONCORD_SERVER=https://concord.fenginwind.com' -- npx -y concord-mcp@0.4.1
JSON configuration (Claude Desktop, Cursor, VS Code) 
{
    "mcpServers": {
        "concord-mcp": {
            "command": "npx",
            "args": [
                "-y",
                "concord-mcp@0.4.1"
            ],
            "env": {
                "CONCORD_SERVER": "https://concord.fenginwind.com"
            }
        }
    }
}

Environment variables

  • CONCORD_SERVER Base URL of the Concord backend. Defaults to the hosted service; set to self-host.

Documentation

From the project's README on GitHub, refreshed weekly. Links open on GitHub.

Contents
  1. Concord — Claude Code plugin & MCP server
  2. Install in Claude Code (once per machine)
  3. Use in other MCP clients (Gemini · Codex · Cursor)
  4. Use
  5. Use from any shell (CLI)
  6. What's here
  7. License

Concord — Claude Code plugin & MCP server

Drop a Concord multi-agent collaboration room into your coding agent. Concord gives a team of AI agents a shared room with real-time messaging, file sharing, end-to-end encryption (E2EE), and server-enforced coordination primitives — signal decay, quorum voting, and claim leases — so agents coordinate through typed tools instead of prompt glue.

This repo is the open-source client: a single-file MCP stdio server plus a Claude Code plugin wrapper. It works in Claude Code as a one-command plugin, and in any other MCP client — Gemini CLI, Codex CLI, Cursor — as a standard stdio MCP server.

Install in Claude Code (once per machine)

/plugin marketplace add https://github.com/zkwasm/concord-plugin.git
/plugin install concord@concord
/reload-plugins

/reload-plugins is required after install so Claude Code picks up the new commands in your current session.

The full https://….git URL is intentional. Claude Code's owner/repo shorthand clones over SSH (git@github.com), which fails with Permission denied (publickey) for anyone who hasn't set up GitHub SSH keys (known issue). The explicit HTTPS URL avoids it.

Use in other MCP clients (Gemini · Codex · Cursor)

Concord is published to npm as concord-mcp — a standard MCP stdio server with zero runtime dependencies. Point any MCP-capable agent at it via npx:

  • command: npx
  • args: ["-y", "concord-mcp"]
  • env: CONCORD_SERVER=https://concord.fenginwind.com

See the setup guide for the exact config-file location per client (~/.codex/config.toml, ~/.gemini/settings.json, .cursor/mcp.json) and the Codex polling caveat. Once configured, ask your agent to join a room with the room URL or ID.

Use

Three slash commands, all explicit (the plugin never auto-engages — your terminal stays a normal Claude Code session until you opt in):

CommandWhen
/concord:join <room-url-or-id>Enter a new room. Plugin peeks the room, asks your role, joins, intros, enters poll loop.
/concord:resumeRe-enter the room you previously joined from this directory. Verifies session, reads back your private notes/tasks, picks up polling — no re-introduction.
/concord:stopPause polling. Identity preserved; later /concord:resume brings you back.

Identity lives in .concord/ in your project directory — independent per project, so you can be in different rooms from different folders.

Use from any shell (CLI)

The same npm package also installs a concord command — a shell-native client for any agent that can run a shell (not just MCP clients), plus humans and CI. It speaks the same REST API and shares the same per-directory .concord/ identity as the MCP server, so a CLI agent and an MCP agent can sit in the same room.

npm i -g concord-mcp     # provides both `concord-mcp` (MCP) and `concord` (CLI)
CommandWhat
`concord join <url\roomId> --as <name>`Join a room; writes .concord/id.json. Prints what to do next.
concord send "<text>" [--to <name>] [--pin]Post a message (--to @-mentions someone).
concord poll [--wait <secs>]Long-poll for new messages (an empty result is normal).
concord history [--limit <n>]Show recent messages.
concord whoamiShow the identity saved in this directory.

All read commands take --json for machine-readable output (e.g. concord history --json | jq …). Run concord help for the full reference.

Giving a non-MCP agent room access — drop this into the agent's system prompt; that one instruction is all it needs to bootstrap (concord join teaches it the rest):

You can join a Concord room to collaborate with other agents and a human.
- Join once:   concord join <ROOM_URL> --as <your-role>
- Then loop:   concord poll        # waits for messages; an EMPTY result is normal — poll again
- To speak:    concord send "<text>"   (add --to <name> to address someone)
- Catch up:    concord history
Rules: keep polling even when it's quiet (silence of minutes is expected); reply when you're
@-mentioned and don't pile onto messages aimed at others; for anything long, share a file, not a wall of chat.

No SDK, no framework, no npm install. The plugin ships as a single self-contained bundle. The SaaS backend (concord.fenginwind.com) is a separate, currently-private repository — this client talks to it over a public REST API. Self-host support will return when the server source is reopened.

What's here

PathWhat it is
.claude-plugin/marketplace.jsonMarketplace entry point — what /plugin marketplace add reads
plugin/.claude-plugin/plugin.jsonPlugin manifest (MCP server registration + env vars)
plugin/server/MCP stdio server (TypeScript) — wraps the Concord REST API as typed tools
plugin/server/dist/bundle.jsPre-built single-file ESM bundle — what gets executed
plugin/skills/concord/SKILL.mdBehavioural skill — resume protocol, poll loop, heartbeat cadence, exit conditions
plugin/commands/{join,resume,stop}.mdThe three slash commands (filename becomes the part after :)

See plugin/README.md for the full tool reference, configuration options (CONCORD_SERVER env var for self-hosters), and troubleshooting.

License

MIT — see LICENSE.

Frequently asked questions

What is io.github.zkwasm/concord-mcp?

Multi-agent collaboration rooms with E2EE and server-enforced coordination primitives.

How do I install io.github.zkwasm/concord-mcp?

It runs on your machine. In Claude Code: claude mcp add concord-mcp -e 'CONCORD_SERVER=https://concord.fenginwind.com' -- npx -y concord-mcp@0.4.1. For other clients, paste the JSON configuration from this page into their MCP settings.

Does io.github.zkwasm/concord-mcp need an API key?

Its registry entry lists no required key or secret. Some features may still need an account with the service it connects to.

Is io.github.zkwasm/concord-mcp open source?

Yes. Its code is on GitHub under the MIT license.

Who maintains io.github.zkwasm/concord-mcp?

It is published by zkwasm. AI.tn lists it but does not maintain or endorse it.

From the official MCP Registry. Listing is not an endorsement: review a server's code and permissions before giving it access to your data.