Jujutsu Workspaces for Subagent Isolation

Overview

A jj workspace is a second working directory attached to the same .jj/repo/ store. It has its own @ (working-copy commit) and its own checkout on disk, but shares the commit graph, bookmarks, and operation log with every other workspace.

Workspaces are an excellent substrate for delegating work to a subagent:

• The subagent gets its own on-disk directory to edit freely.
• Any commit it makes is immediately visible in the main workspace — no pull, fetch, push, or merge step.
• When the subagent finishes, the main agent can rebase, squash, or reorder the resulting commits into the user's stack with normal jj operations.
• Cleanup is two commands.

Core principle: the workspace is the subagent's sandbox; the commit graph is the shared output channel.

This skill covers only the jj side. How you spawn a subagent (shell exec, Task tool, API call, MCP, etc.) is intentionally out of scope — the workflow only requires that you can run the subagent with a chosen working directory.

When to Use