Skills

A skill is a folder of instructions, scripts and reference files for one kind of task, such as filling PDF forms or writing release notes in your house style. You add it once under Skills, attach it to the jobs that need it, and every run of those jobs finds it in /ump/skills/<name>.

Skills use the same format as Claude’s agent skills, so a folder from anthropics/skills or one you built for Claude Code works as it is.

A skill folder

A skill needs a SKILL.md whose frontmatter names the skill and says when to use it:

---
name: pdf-forms
description: Fills PDF forms from structured data. Use when a job has to complete or read a PDF form.
---

# PDF forms

Run `scripts/fill.py <form.pdf> <data.json> <out.pdf>` to fill a form.
Field names and their quirks are in [reference.md](reference.md).

The name takes lowercase letters, digits and single hyphens, up to 64 characters, and must be unique in the workspace. The description takes up to 1,024 characters without XML tags. Write it for the agent: say what the skill does and the situations that call for it, since the agent sees only this line until it opens the skill. Umpteenth ignores the other frontmatter keys, such as license.

Everything else in the folder is yours to arrange. A script keeps its executable bit from the zip, and a file that starts with #! becomes executable even from a zip made on Windows.

Add a skill

Open Skills, click Add skill and pick where the skill comes from.

Under Link, paste the GitHub address of the skill’s folder, such as https://github.com/anthropics/skills/tree/main/skills/pdf, and click Add skill. A link to the folder’s SKILL.md or to a repository that holds a single skill works too, and so does a link to a .zip or .skill file on any server. Umpteenth downloads public repositories only.

A repository such as https://github.com/crowdin/skills holds several skills, and a link to it or to the folder they share lists them in the dialog. Tick the ones you want and click Add 2 skills (the button counts your picks), and each skill keeps the link to its own folder for later updates. The list greys out the skills your workspace already has and those with a broken SKILL.md, with the reason under the name.

Under Upload, pick a zip of the folder, with SKILL.md at the root of the zip or inside one top-level folder. A .skill file from Claude is such a zip.

Umpteenth checks the skill before storing it and shows what is wrong next to the field. A skill may hold up to 500 files and 32 MiB, and a zip may be 8 MiB. Umpteenth refuses symlinks, encrypted entries and paths outside the skill folder, and drops the __MACOSX folder and .DS_Store files that macOS adds.

Click a skill to see its files, read its SKILL.md and open any other file.

Attach skills to a job

In the job’s Settings tab, pick a skill from Attach skill in the Skills card and click Save. A job takes up to 20 skills with 64 MiB of files in total.

The New job review screen has the same Skills card. The compile step compares your description with each skill’s description and attaches the ones that fit, marked Suggested. Attach skill opens a list of your other skills that you can search by name or description.

Skills in a run

Before the agent starts, Umpteenth copies the job’s skills into the sandbox and notes Added the skill pdf-forms on the run’s timeline. The agent’s instructions list each skill’s name, description and the path of its SKILL.md. The agent reads a SKILL.md once a task fits it and opens the other files it links to only when it needs them, so ten attached skills cost the model little more than ten lines.

The files belong to root, so the agent can read and run them but not change them, unless the job has Run as root on. A graduated job’s main script can call a skill’s scripts by their path, such as /ump/skills/pdf-forms/scripts/fill.py, and Umpteenth tells reflection to call them there rather than copy them into the playbook.

Replace or delete a skill

A skill added from a link keeps it, and Update from link in the skill’s menu downloads the current version from there. Replace takes a new version from a link or an upload, and an upload drops the skill’s link. Its SKILL.md must keep the same name, because jobs and their scripts find the skill by its folder; add a renamed skill as a new one. Runs that start after the change get the new version.

Delete removes the skill and detaches it from every job, and the confirmation says how many jobs use it. To delete several at once, tick their checkboxes on the Skills page and click Delete above the table. Download gives you the stored zip back.