Skills

A skill is a packaged procedure — a folder under .claude/skills/ whose entry point is a SKILL.md file. When a task matches a skill's description, an agent loads the skill and follows its method instead of improvising; you can also invoke one directly by name (/skill-name) in any Claude session. The Skills view is where you browse, inspect, edit, and author them.

Open it from the sidebar, in the Agents section: Skills.

How skills work

Three facts explain the whole layer:

• A skill is registered by existing. A directory in .claude/skills/ with a SKILL.md is a skill — no manifest, no build step, no registration. Saving the file is the deployment; the next invocation reads it fresh.
• The description is the gate. Agents decide whether to load a skill by its frontmatter description. A precise, keyword-rich description that says when to use the skill — and when not to — is the single highest-leverage line in the file.
• Skills disclose progressively. A good SKILL.md stays lean and defers its bulk to sibling files in the same folder (references, templates, assets) that load only when needed. This keeps the always-loaded cost of a skill small.

Skills come in three postures: auto (agents invoke it when the description matches), human-only (only you can trigger it, by name), and forked (it runs in its own isolated context and returns a result). The posture is set by frontmatter flags.

Browse and inspect

The view is three panes:

• Left — a card per skill: its name and the first line of its description.
• Middle — the skill folder's file tree, with SKILL.md pinned at the top. Sibling reference files, templates, and assets are all visible here; a skill is its whole folder, not just the entry file.
• Right — the editor. Markdown files open with a rendered/raw toggle; other files open directly for editing.

Reading a skill top-to-bottom is the reliable way to know exactly what an agent will do when it invokes it.

Edit a skill

1. Select the skill, pick the file (start with SKILL.md), switch to edit mode.
2. Make your change — tighten a rule, fix a step, extend a reference file.
3. Save. That is the entire deploy: the next /name invocation or auto-match reads the updated file. No restart anywhere.

You can also add a new file inside a skill from the middle pane — the standard move when SKILL.md grows too long and detail belongs in a sibling reference file. Deleting a file or a whole skill moves it to the system trash, so mistakes are recoverable.

Create a skill

Two paths, depending on how much help you want:

The Create/Clone dialog (the + New skill button, or Clone on an existing skill) scaffolds the folder and a valid SKILL.md frontmatter for you — you write the content. It validates the frontmatter as you go, and the created skill opens in the view, live immediately. Cloning a proven skill and editing it is the fastest route to a working custom skill.

The skill-builder skill (/skill-builder in any Claude session) is the assisted route: it interviews you — goal, trigger, auto vs. manual, workflow, reference files, guardrails — and then designs and writes a complete, production-quality skill for you, sibling files included.

Whichever path you take, three authoring rules pay off:

1. Invest in the description. State what the skill does, when to use it, and when not to — including pointing to a sibling skill when one covers an adjacent case. This is what makes auto-invocation land on the right skill.
2. Keep SKILL.md lean. Move detailed references, mappings, and templates into sibling files the skill points at.
3. Add explicit rules. A short block of hard constraints ("always X, never Y") does more for output quality than paragraphs of prose.

One formatting rule shared with agents: the frontmatter is strict YAML — inside a description value, write — (a dash) rather than a colon followed by a space.

Skills, agents, and protocols

The three doctrine layers divide cleanly: an agent is who does a job (an identity with tools and a model), a skill is how a specific kind of task is done (a reusable procedure any agent can load), and a protocol is a standing rulebook multiple agents obey (browsable in the Protocols view, editable the same way). All three are hot-reloaded Markdown — improving your system is editing files, never redeploying software.

Where to go next

• The skills catalog — every shipped skill and what it is for
• Agents — the roster that invokes these skills
• The operator model — the file-based competence model skills belong to