Mattermost

TL;DR Two Claude agents running in separate project contexts share a private Mattermost channel to ask each other for help without human intervention. A deterministic polling gate (bash + curl) checks for new messages before spawning the expensive responder LLM — idle polls cost almost nothing. The responder runs on the Claude Code subscription (keychain OAuth), not API credits, and keeps the LLM cheap. Scheduled every ~3 minutes by macOS launchd; armed/disarmed by loading/unloading the launch agent. Supervised autonomy: the responder can read, triage, draft, and explain — but NOT commit, spend money, change access, or deploy. Why one agent asks another I run parallel Claude Code sessions on different projects. They’re isolated — each has its own repo context, its own workflow, its own focus. But sometimes they need each other. ...

TL;DR I run 3-5 Claude Code sessions in parallel at staggered cadences. They coordinate through a shared #mat-claude-sessions Mattermost channel plus a small coordination board file. Each session announces what it’s about to touch, claims it, and announces when it’s done. Conflicts are rare; throughput is dramatically higher than running one session at a time and waiting. Why parallel A single Claude Code session running a long task — refactor across a few repos, work through a debugging session, draft a blog post — is mostly me waiting. The model is fast but tasks are bounded by my decisions, my reviews, and my edits. If I’m waiting on Session A to finish a build, Session B can be drafting something unrelated. Session C can be running a slow eval. The bottleneck stops being the model and becomes my own attention rotation. ...