What problem does it solve? Teams using jj (jujutsu) instead of git need agents that understand its different mental model: no staging area, change IDs instead of commits, and editor-invoking commands that hang non-interactive shells. This Skill prevents the classic failure where jj commit or jj describe silently waits for an editor that never opens, and teaches safe patterns for parallel agents sharing one working copy. ## Core Features & Use Cases - Hang prevention: Enforces -m "msg" or -u on describe, commit, squash, and split so jj never opens an interactive editor in an automated shell. - Parallel-agent safety: Prefers explicit change IDs over @/@-, warns against jj restore on mixed working copies, and mandates jj diff -r @- --stat verification after selective commits. - Selective commits and squashing: Covers cwd:"..." fileset wrapping for paths with [/], jj split/jj squash --from/--into workflows, and a recipe for collapsing ~10 session commits into 1-2 clean ones. - Use Case: An agent finishing a feature runs jj commit -m "msg" -- 'cwd:"apps/www/src/routes/[id]/+page.svelte"', verifies the file list with jj diff -r @- --stat, then squashes fixups into the parent with jj squash -r <id> -u before pushing a bookmark and opening a PR. ## Quick Start Use the jj skill to commit my current changes with a proper message and verify nothing was left stranded in the working copy.