> ## Documentation Index
> Fetch the complete documentation index at: https://docs.comet.rpamis.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Skill types and purpose

> Understand Comet's Skill sources, discovery priority, and the boundaries classic Spec-mode users need to know.

Comet organizes its behavior through Skills. Users normally invoke only `/comet`, which selects Native or Classic from project configuration. After entering Classic Spec mode, you do not need to understand every Engine detail.

## Where Skills live

| Installation path         | Target directory                             | Who discovers it                   | Notes                                                  |
| ------------------------- | -------------------------------------------- | ---------------------------------- | ------------------------------------------------------ |
| `comet init`              | Platform directory such as `.claude/skills/` | The AI platform                    | Built-in workflow Skills become slash commands.        |
| `comet skill add`         | `.comet/skills/<name>`                       | Comet Engine                       | Project Skills do not directly appear in the platform. |
| Generated by `/comet-any` | Bundle draft directory                       | Distributed after eval and publish | Skill Creator output.                                  |

<p align="center">
  <img src="https://mintcdn.com/comet-bb5f5294/sd_slIArmm0kHnD4/assets/skills-illustrations/01-skill-source-greenhouse.png?fit=max&auto=format&n=sd_slIArmm0kHnD4&q=85&s=d2d438cec343869b84ee80323ed8c558" alt="Xiaoyu sorts platform Skills, project Skills, and generated Skills in a small greenhouse by source and discovery mechanism" width="800" data-path="assets/skills-illustrations/01-skill-source-greenhouse.png" />
</p>

<p align="center">
  Different Skill sources are discovered by different mechanisms. Project Skills can override
  built-ins, but invalid overrides fail closed.
</p>

<Note>
  <strong>Platform Skills</strong> are installed into a platform directory and become slash
  commands. <strong>Project Skills</strong> live in <code>.comet/skills/</code> and are resolved by
  Comet Engine at runtime.
</Note>

## Project Skills

A project Skill is a Skill package installed under `.comet/skills/<name>/`. It belongs to the repository and can be committed to Git.

Discovery priority is explicit path -> project Skill -> built-in Skill. If a project Skill shadows a built-in Skill but fails validation, Engine fails instead of silently falling back. That protects teams from thinking they are using a custom workflow when the built-in one is actually running.

### Why use project Skills

| Use case              | Why it helps                                                     |
| --------------------- | ---------------------------------------------------------------- |
| Override built-ins    | Standardize a team-specific `comet-build` or similar Skill.      |
| Install Engine Skills | Use `/comet-any` output or community Skills inside this project. |
| Share through Git     | Clone the repository and get the same Skill pool.                |

Install one with:

```bash theme={null}
comet skill add ./my-skill --project .
```

## Local Skill commands

| Command                | Purpose                                                          |
| ---------------------- | ---------------------------------------------------------------- |
| `comet skill add`      | Install a Skill package into `.comet/skills/`.                   |
| `comet skill show`     | Inspect source, hash, structure, guardrails, and runtime checks. |
| `comet skill run`      | Start an advanced deterministic Engine Run.                      |
| `comet skill continue` | Resume a run or submit pending action output.                    |
| `comet skill check`    | Run Engine runtime checks.                                       |

## Built-in classic workflow Skills

| Skill                            | Purpose                                                                  |
| -------------------------------- | ------------------------------------------------------------------------ |
| `/comet-classic`                 | Main Classic entry point. Detects state and routes to the current phase. |
| `/comet-open`                    | Creates an OpenSpec change.                                              |
| `/comet-design`                  | Produces deep technical design.                                          |
| `/comet-build`                   | Plans and executes implementation.                                       |
| `/comet-verify`                  | Verifies implementation and branch state.                                |
| `/comet-archive`                 | Archives the change.                                                     |
| `/comet-hotfix` / `/comet-tweak` | Lightweight presets.                                                     |

These Skills ship with Comet and are installed into platform directories by Classic initialization. Normally, invoke `/comet`; when configuration selects Classic, the internal `/comet-classic` entry detects state and invokes the appropriate phase Skill.

## Creating reusable Skills with /comet-any

`/comet-any` is the user-facing Skill Creator path. It reads project preferences, resolves real local Skill content, presents a confirmation page, then generates a stable Skill Bundle with Skill text, references, scripts, rules, hooks, and evidence.

```text theme={null}
/comet-any -> comet eval -> comet creator status/next -> review/approve/run -> distribute
```

Implementation terms such as Bundle, Factory, and Phase Recipe stay internal. From the user perspective there are three starts: customize `/comet-classic`, create a new Skill, or upgrade an existing Skill.

Classic `/comet-classic` users do not need to understand Engine internals to use the five-phase workflow.

## Next steps

* [Workflow concepts](/en/concepts/workflow) — how `/comet-classic` connects the five phases
* [State and configuration](/en/concepts/state-management)
* [Skill and Engine](/en/skill-creator/engine)