Packslip Completions and Skills

Tools installed with the packslip backend can provide completions and agent skills for the version active in your project. The vendor declares these resources in its release manifest; mise fetches them with the tool and exposes them to your shell or agent.

A tool installed through another backend does not acquire these resources just because its publisher also ships a packslip. The installed version must have Packslip metadata, and that manifest must declare the resource you want.

The examples below use mytool for an installed executable that declares completions or skills. Replace it with your command's name.

Completions

First, print the completion script to check that the active tool provides one:

mise completion zsh --tool mytool

Then install a stub for the command:

mise completion zsh --tool mytool --install

--install takes the executable name as typed, such as mytool, rather than a backend identifier containing slashes. For a release with several commands, choose the command you want to complete. Without --tool, mise completion generates completions for mise itself.

The command writes a completion file but does not edit your shell configuration. Follow any one-time setup line it prints, then load the completion file or start a new shell. It preserves an existing file that mise did not create unless you explicitly pass --force.

Follow the active version

The installed stub asks mise for the script when you complete the command. It does not generate a completion by running the vendor tool at shell startup. After you change directories or select another version with mise use, the next completion uses that directory's active version.

Shell	How the installed stub follows version changes
zsh	Temporarily hands a completion to the vendor script, then restores mise's stub.
bash	Hands completion to the vendor registration and restores the stub at the next prompt.
fish	Loads the vendor script in a child shell for each completion, keeping registrations out of the parent shell.
PowerShell	Hands a completion to the vendor completer, then restores mise's completer.

These four are the shells mise completion knows, for --tool with and without --install. A tool's packslip completions are not available in any other shell.

Static files, usage specs, and generated scripts

mise prefers a completion file supplied by the vendor, then a script derived from a static usage CLI spec, then a vendor command that generates a completion or CLI spec. Selection is scoped to the installed artifact, executable, and shell.

Usage-derived completions require the usage command both to generate the script and at shell runtime:

mise use -g usage

If the only usable source runs the vendor executable, mise runs it on demand and caches successful output per installed version, executable, and shell. Concurrent requests share that work. Empty output, a failure, or a timeout does not become a cached script; mise tries the next source.

Only generation takes turns, and only generation writes: a completion the release ships is read straight out of the install, so a read-only system or shared install still completes.

Calling mise completion ... --tool directly can also trigger generation. The packslip.exec setting does not gate on-demand completion generation. It controls resource commands run during installation, such as generated skills.

Skills

A skill is a directory containing SKILL.md and any supporting files. mise fetches declared skills during tool installation by default, so different tool versions can carry different skill content.

Inspect the installed skills of tools active in the current directory:

mise skills ls
mise skills ls --json

Link them where your agent reads skills:

mise skills sync --dir .agents/skills

By default, mise skills sync uses .claude/skills under the nearest mise project root. --dir selects a directory for that invocation. --global instead resolves the configured skill directory under your home folder. With the default setting, that is ~/.claude/skills.

Each link points into the active tool version's install directory. Run sync after a version change to update those links. Only mise-owned links are replaced; a user-created directory or unrelated link at the same name is preserved and reported as skipped.

Keep project links up to date

Configure your agent's directory and enable synchronization after mise install and mise use:

[settings.skills]
dir = ".agents/skills"
auto_sync = true
prune = true

prune = true also removes mise-owned links for skills no longer active. Without it, stale links remain. To prune on one manual run:

mise skills sync --dir .agents/skills --prune

Automatic sync requires a mise project root. It does not run merely because you change directories, and it does not change an already running agent's skill-loading behavior. Reload skills as your agent requires.

Choose whether to fetch or generate skills

Setting	Default	Effect
skills.fetch	true	Fetch declared skills while installing tools.
skills.dir	.claude/skills	Choose the directory used by sync.
skills.auto_sync	false	Sync after install and use within a mise project.
skills.prune	false	Remove stale mise-owned links during sync.
packslip.exec	false	Allow running the installed tool to produce a resource during installation.

A skill can be fetched from the artifact, a separate signed asset, or the source repository at the release commit. A skill offered only as an exec command is generated during installation only when packslip.exec is enabled. That command runs the newly installed vendor executable and must print SKILL.md content. Fetched skills do not require executing the tool.

Turning off skills.fetch affects skill fetching during installation; it does not delete previously fetched files or existing links. Run sync with pruning when you want to remove links to inactive skills.

Resource selection and command execution

Resources can target an exact artifact filename or a platform. mise selects resources for the artifact it installed, preferring exact artifact scope and then the most specific platform scope. Different executables, shells, and skill names identify separate resources.

Within an identity, equally scoped sources are alternatives. mise prefers an archive file, then a signed asset, then a source-repository file. Static CLI specs follow the same ordering. Declaration order breaks ties within a source type. A usable higher-priority skill source prevents fetching or running lower ones. A directory counts as a skill only when SKILL.md is present.

Separate resource assets must match their signed digests; repository resources are pinned to the release's source commit. A missing optional resource can leave the tool installed without it. A digest mismatch is a verification failure, not permission to choose an unverified alternative.

When mise runs a resource generator, it:

• Adds the installed executables to PATH and applies the manifest's environment variables, expanding {shell} for completion resources.
• Uses a temporary working directory, no stdin, and discarded stderr.
• Enforces a five-second deadline and a 4 MiB output limit, and cleans up child processes after completion, failure, timeout, or cancellation.

These limits bound generation; they do not make vendor code a sandboxed program. The backend trust checks establish which publisher's executable is being used.

Troubleshooting

Symptom	What to check
Tool was not installed from a packslip	Check the active tool's backend and version with mise ls.
No completion declared	Check whether the release declares a matching shell, command, or usage spec. For multiple executables, pass the command name.
--install rejects a tool identifier	Use the executable name, not packslip:host/owner/repo.
A completion file already exists	Inspect its source before choosing whether to replace it with --force.
Script prints but tab completion does not work	Follow the shell setup printed by --install; check that the stub is loaded and usage is on PATH if required.
Completion generation fails	Check whether the vendor command emits nonempty output within the time and size limits.
No skills listed	Check the active installed version, its declared resources, skills.fetch, and whether SKILL.md is present. An exec-only skill also needs packslip.exec at installation.
A skill link is skipped	A user-owned file or directory may occupy its name; mise leaves it intact.
Links still point to an old version	Run mise skills sync after changing versions, or enable automatic sync.

For exact flags, see mise completion, mise skills ls, and mise skills sync. Publishers can follow the Packslip resources guide to add these declarations to their releases.