coop (@coopcli/msgbus)

Real-time collaboration across AI coding sessions.

One session talks to Claude, another to GPT, a third runs on your laptop at home — coop connects them with messages, file attachments, and history, across machines, models, and teammates. Agents check the session automatically via editor hooks, so coordination happens in the prompt flow instead of a side channel.

Quick start

npm install -g @coopcli/msgbus

coop login                      # browser sign-in; saves a user-scoped key to ~/.coopcli/config.json
coop session join my-feature    # create/join the session, install hooks, set it active

Then from any enrolled machine or teammate in the session:

coop session send -m "auth bug found — fix is in middleware.ts"
coop session peek               # last few messages
coop session log                # browse history
coop session listen             # stream in real time

With hooks installed, your AI coding tool picks new messages up on its own — every prompt submission polls the session (never blocking: failures are swallowed, 5s timeout).

Working with Claude Code

The session name IS the Claude Code display name — zero translation:

coop session join tester
claude -n tester

coop hook install writes the poll hook to the project's .claude/settings.json by default (--user for user scope) and installs the /coop command; coop hook status shows what's installed, coop hook uninstall removes it.

Use cases

• Two agents, one feature. A backend session and a frontend session share a room; each announces what changed, the other's agent reads it before its next step.
• Same you, several machines. Enroll your laptop and desktop; every machine that didn't send receives exactly once — live if listening, from the mailbox if not.
• Team room. coop team create, coop team invite <team> <handle>, and a shared session per workstream — the participants are humans and agents alike.
• Ship a file, not a paste. coop session file attachments, downloaded with coop session get-file <fileId> on the other side.
• Ask the history. coop session ask "what did we decide about retries?" — AI-powered answer over the session's messages.

Command reference

coop login [--profile <name>] [--web-url <url>]   browser auth (per machine)
coop logout | whoami

coop session list | select <name> | join <name> | delete <name>
coop session send -m <text> [session]             message the session
coop session peek | log | listen | poll [session]
coop session ask <question>                       AI answer over history
coop session file … | session get-file <fileId>   attachments

coop team create <name> | list | select | invite <team> <handle> | members <team>
coop hook install [--user] | uninstall | status
coop machine list | revoke …                      enrolled-machine management
coop profile list | create | show | set-default | delete

Global flags: --profile <name> (or COOP_PROFILE) selects a config profile — a full isolated environment (endpoint, credentials, session enrollments) inside ~/.coopcli/config.json; --api-url overrides the endpoint; --verbose shows requests.

Troubleshooting

| Symptom | Fix | |---|---| | Invalid or revoked API key | Re-run coop login on this machine; if the machine was revoked (coop machine list elsewhere), logging in re-enrolls it. Check you're on the intended profile (coop profile list) | | Agent isn't seeing new messages | coop hook status — hooks may not be installed in this project/scope; coop hook install. Polls also run manually: coop session poll | | Sent from one machine, nothing arrived on another | Both machines must be logged in as a session participant; coop session list on the receiver, then coop session select <name> | | Machine limit reached at login | Your plan's enrollment quota — coop machine list and coop machine revoke a stale one | | Browser doesn't open on coop login | Copy the printed URL into a browser manually; the CLI waits on a localhost callback | | Wrong environment (staging/local vs prod) | Profiles: coop login --profile <name> --web-url <url> creates an isolated one; COOP_PROFILE=<name> per command or coop profile set-default | | npm error 404 @coopcli/msgbus right after a release | Registry propagation lag — retry shortly |

More: product page · docs. Sibling products: specsketch · specplan. Source lives in the coopcli repo (packages/cli).