The Folder

What You Are Looking At

A Claude Skill is a folder. Anthropic's own Skills documentation — the Help Center articleWhat are Skills?, the Claude Code Skills page, and theAgent Skills specification — describes the same object: a SKILL.md entrypoint with a name, adescription of when to use it, and instructions, plus optional files the agent reads only when the procedure points at them. That is the whole mechanism. It is not a prompt snippet, because it can carry files. It is not an MCP server, because the unit is a package you can open.

The Folder on this page is a labeled editorial specimen. Every line invendor-invoice-audit was written here to teach that anatomy. It is not a file from anthropics/skills, and it is not a substitute for the official examples in the directory. If you need a pattern from Anthropic, open their repository. If you need to see which part ofSKILL.md does which job, stay on this desk.

How To Write One

Name one recurring job. A skill that "helps with finance" will fire on everything and help with nothing. A skill that reviews a vendor invoice against a contract and a purchase order can be tested. Write the non-goals next to the goal. The Help Center page on creating custom Skillsand the Agent Skills best practicesboth start from a focused workflow rather than a dump of instructions.

Write the description before the body. That field is not marketing copy. It is the matching rule Claude uses to decide whether to load the folder. Include the task, the artifacts, and the exclusions. "Use when reviewing vendor invoices against contracts and purchase orders" can be evaluated. "Use for finance excellence" cannot. If the skill fails to trigger, revise this sentence before adding paragraphs.

Write the procedure as steps a careful operator would follow. Tell the agent what to collect first, which file to open next, what to stop for, and what the output should look like. Point at references/ and examples/ with paths one level deep. Leave scripts and assets out of this specimen on purpose: they are part of the portable folder format, which Convergent Skillsowns, not a requirement for a first Claude Skill.

Evaluate before you share it. Positive prompts should load the skill. Near-miss prompts should not. Safety prompts should pause. Thetrigger tester on this site is a scratchpad for that wording; the evaluation guide is the loop once the folder is real.

Where The Other Desks Are

The portable skill format — how an agent loads metadata, then the body, then scripts, references, and assets, and how far that directory travels across clients — isThe Skill Folder at convergentskills.com. That route is theirs. This one is /folder/, and it stays on Claude Skill authoring.

Using a skill inside a Claude Code engineering practice — hooks, subagents, CI, MCP, marketplace plugins as a workflow — belongs atclaudeshipscode.com. This site tells you where a Claude Code skill folder is installed. It does not become a Claude Code tutorial.

Why The Specimen Is Editorial

Copying an official Anthropic skill onto this page would teach the wrong lesson: that the way to understand Skills is to republish someone else's procedure. Official examples are already public, already linked from the directory, and already changing. A teaching specimen has a different job. It has to be short enough to label, dull enough not to be stolen as a product, and honest about being ours.

So we wrote a vendor-invoice audit. The job appears in the authoring guide as a description example; the folder here is the same job made inspectable. No real vendor, invoice, or contract is in it. The exception rules are invented policy for the specimen. Cite it as an illustration of anatomy, never as an Anthropic artifact.