Cowork

Muster runs in Claude Cowork through a local MCP server. The neutral core is mcp/server.mjs; mcp/codex-server.mjs, mcp/chatgpt-work-server.mjs, and cowork/mcp-server.mjs are explicit host adapters. The old cowork/chatgpt-work-server.mjs path remains a compatibility shim. Model work uses the active Cowork account or subscription.

Support matrix

Capability	Cowork support
Routing, manifests, waves, and gates	Native MCP tools
Tool inventory	31 tools: 30 CLI-wrapper tools plus muster_sprint_protocol
Parallel subagents	Conditional; run probe phase 3 on the active build first
Sequential execution	muster_next fallback
Per-agent worktree isolation	No proven native primitive
Hooks and action fence	MCP-only lane has none
Native Muster plugin	Unverified; declared through MUSTER_COWORK_NATIVE_PLUGIN
Remote connectors	Declared through MUSTER_COWORK_CONNECTORS

The server exposes 31 tools in total: 30 CLI-wrapper tools plus muster_sprint_protocol. The protocol returns the Cowork-adapted backlog playbook. It is a protocol tool, not a CLI wrapper.

Backlog writes use muster_backlog_publish, a compare-and-swap publication tool. Pass the complete next content plus the lowercase SHA-256 of the version you read (or absent for creation). A concurrent-writer mismatch fails closed; reread, reapply your change, and retry instead of overwriting another runner's update.

The repository tests verify probe phases 1 and 2: CLI portability and the dispatch contract. They do not contain a live phase-3 receipt. Run node scripts/cowork-probe.mjs, execute its phase-3 spec in the active Cowork build, and grade the returned results before relying on parallel dispatch or per-call model override. Until that passes, use the sequential muster_next path.

Configure the local server

Add a muster entry to Cowork's MCP configuration and point it at the Cowork adapter cowork/mcp-server.mjs (the canonical core is mcp/server.mjs):

{
  "mcpServers": {
    "muster": {
      "command": "node",
      "args": ["/absolute/path/to/muster/cowork/mcp-server.mjs"]
    }
  }
}

Use Node 20 or newer on the host path, then fully restart Cowork. Connect or trust the project folder before asking Cowork to read it. Verify by listing muster_* tools and calling muster_detect with the project directory.

Backlog runs

Call muster_sprint_protocol before a Cowork backlog clear. It names backlog resolution, dependency waves, per-item lifecycle, and claim receipts. After each worker wake, use muster_sprint_reconcile to drain all receipts and dispatch every newly eligible action before waiting again. Without a proven native per-subagent worktree primitive, the orchestrator creates a dedicated isolated Git worktree for each write-capable wave item and executes those items sequentially in their assigned worktrees. The connected project is the coordination and ordered-integration surface, not the fallback implementation workspace. Prefer pr or keep dispositions over direct base-branch merges.

Cowork's native plugin loader may eventually carry Muster's skills, hooks, and agents. That path is not auto-detected. Leave MUSTER_COWORK_NATIVE_PLUGIN unset unless a live Cowork session has loaded the plugin and exposed those capabilities.

See Configuration for connector declarations, native-plugin declaration, concurrency, and queue limits.