| disable-model-invocation | false |
| name | cli-just |
| user-invocable | false |
| description | Use for just/justfile task automation: create justfiles, write recipes, configure settings, add modules/attributes, or set up command-runner workflows. |
Just Command Runner
Create readable task automation that matches the repository's installed Just version and existing justfile conventions.
Defaults
-
Inspect just --version, the existing justfile/module tree, and just --list before editing. Installed capabilities
and existing syntax are authoritative over this skill's examples.
-
Preserve bespoke formatting. Do not rewrite a justfile with just --fmt; use just --fmt --check only when the
repository explicitly treats the built-in formatter as authoritative. just --dump is inspection output, not a
formatting source.
-
Define multi-item string sequences one item per line with a parenthesized concatenation. Keep a trailing separator in
every non-final item; do not collapse them into one long string. Triple-quoted strings are for values whose newlines
are semantic, not visual wrapping. For example:
check-steps := (
"event-class-coverage " +
"orphan-disposal " +
"price-coverage"
)
-
Prefer explicit, small recipes; require() for tool dependencies; private helpers; check/write recipe pairs; and
aliases after their target recipes.
-
Make recipes quiet by default: prefix the recipe name with @ unless echoing commands has clear value. Recipe-level
@ inverts per-line @, so never also prefix lines inside a @recipe. Never add @ to a [script] recipe: scripts
are already quiet, and @ un-mutes them. See "Quiet Recipes and Command Prefixes" in references/recipes.md.
-
On stock macOS, assume /bin/bash 3.2 unless the recipe explicitly selects a newer shell.
-
Use the user's section-banner style when creating a new standalone justfile; existing repository organization
overrides it.
Workflow
-
Determine the requested recipe behavior, inputs, outputs, cwd, shell, environment, dependencies, and success
condition.
-
Use the installed manual (just --help, just --man, or https://just.systems/man/en/) for version-sensitive
syntax. Read only the task-specific reference:
| Task | Reference |
|---|
| Recipes, parameters, dependencies, cache | references/recipes.md |
| Settings, dotenv, lists, modules | references/settings.md |
| Expressions, functions, constants | references/syntax.md |
| Shell or script recipes | references/inline-scripts.md |
| Check/write, status, aliases, organization | references/patterns.md |
-
Make the smallest recipe or setting change. Do not enable unstable features unless the requested design needs them
and the installed version supports them.
-
Validate parsing with just --list or just --summary, then execute the narrowest safe recipe path. For
state-changing recipes, use an existing dry-run/check mode or inspect the expanded command first.
Opinionated Organization
For a new standalone file, prefer dependency declarations, constants, public recipes, checks, then private helpers. Use
set default-list := true when no single default action makes sense and the installed version supports it. Example
starting points live in examples/standalone.just and examples/devkit.just; load one only when creating that shape.
Completion requires a parsable justfile, the requested recipe behavior, and execution or dry-run evidence appropriate to
its side effects. Finish with ### ✅ Just workflow ready, a compact recipe/alias/purpose table when several entries
changed, and ### 🧪 Verification with exact commands and outcomes. Keep confirmation prompts, recipe data output,
compiler output, and just --list output undecorated; preserve the repository's own banner vocabulary.