> omk can create skills. Ask it to build one for your use case.

# Skills

Skills are self-contained capability packages that the agent loads on-demand. A skill provides specialized workflows, setup instructions, helper scripts, and reference documentation for specific tasks.

OMK implements the [Agent Skills standard](https://agentskills.io/specification), warning about most violations but remaining lenient. OMK allows skill names to differ from their parent directory even though the standard disallows it; that rule is suboptimal for shared skill directories used across multiple agent harnesses.

## Table of Contents

- [Locations](#locations)
- [How Skills Work](#how-skills-work)
- [Skill Commands](#skill-commands)
- [Skill Structure](#skill-structure)
- [Frontmatter](#frontmatter)
- [Validation](#validation)
- [Example](#example)
- [Skill Repositories](#skill-repositories)

## Locations

> **Security:** Skills can instruct the model to perform any action and may include executable code the model invokes. Review skill content before use.

OMK loads skills from:

- Global:
  - `~/.omk/agent/skills/`
  - `~/.agents/skills/`
- Project:
  - `.omk/skills/`
  - `.agents/skills/` in `cwd` and ancestor directories (up to git repo root, or filesystem root when not in a repo)
- Packages: `skills/` directories or `omk.skills` entries in `package.json`
- Settings: `skills` array with files or directories
- CLI: `--skill <path>` (repeatable, additive even with `--no-skills`)

Discovery rules:
- In `~/.omk/agent/skills/` and `.omk/skills/`, direct root `.md` files are discovered as individual skills
- In all skill locations, directories containing `SKILL.md` are discovered recursively
- In `~/.agents/skills/` and project `.agents/skills/`, root `.md` files are ignored

Disable discovery with `--no-skills` (explicit `--skill` paths still load).

### Using Skills from Other Harnesses

To use skills from Claude Code or OpenAI Codex, add their directories to settings:

```json
{
  "skills": [
    "~/.claude/skills",
    "~/.codex/skills"
  ]
}
```

For project-level Claude Code skills, add to `.omk/settings.json`:

```json
{
  "skills": ["../.claude/skills"]
}
```

## How Skills Work

1. At startup, omk scans skill locations and extracts names and descriptions
2. The system prompt includes available skills in XML format per the [specification](https://agentskills.io/integrate-skills)
3. When a task matches, the agent uses `read` to load the full SKILL.md (models don't always do this; use prompting, `/skill:name`, or `!skill:name` to force it)
4. The agent follows the instructions, using relative paths to reference scripts and assets

This is progressive disclosure: only descriptions are always in context, full instructions load on-demand.

## Skill Commands

Skills register as `/skill:name` commands and interactive `!` launcher entries:

```bash
/skill:brave-search           # Load and execute the skill
/skill:pdf-tools extract      # Load skill with arguments
!skill:brave-search           # Load and execute from the bang launcher
!brave-search query           # Shorthand when brave-search is a known skill
!omk frontend build a navbar  # Route through OMK role hubs, selecting omk-frontend
```

Arguments after the command are appended after the skill content for the current turn.

`!omk <role-or-request>` is a deterministic OMK hub router. Exact role aliases such as `frontend`, `backend`, `loop`, and `plan` select `omk-frontend`, `omk-backend-data`, `omk-loop`, and `omk-plan`; free-form prompts are scored against the same hub vocabulary and fall back to `omk-skills` when no role is clear.

In interactive mode, type `!` to open skill autocomplete. Selecting a skill inserts the explicit `!skill:name ` form, and `!omk` is offered when the OMK skill hub index is available. Bash remains available as `! command`, and `!! command` runs bash without sending output to the model. If `!token` is not a known skill, it falls back to bash; use `! command` when a command name might collide with a skill. `!omk` is reserved for OMK hub routing and never falls through to bash.

Toggle skill commands via `/settings` in interactive mode or in `settings.json`:

```json
{
  "enableSkillCommands": true
}
```

## Skill Structure

A skill is a directory with a `SKILL.md` file. Everything else is freeform.

```
my-skill/
├── SKILL.md              # Required: frontmatter + instructions
├── scripts/              # Helper scripts
│   └── process.sh
├── references/           # Detailed docs loaded on-demand
│   └── api-reference.md
└── assets/
    └── template.json
```

### SKILL.md Format

````markdown
---
name: my-skill
description: What this skill does and when to use it. Be specific.
---

# My Skill

## Setup

Run once before first use:
```bash
cd /path/to/skill && npm install
```

## Usage

```bash
./scripts/process.sh <input>
```
````

Use relative paths from the skill directory:

```markdown
See [the reference guide](references/REFERENCE.md) for details.
```

## Frontmatter

Per the [Agent Skills specification](https://agentskills.io/specification#frontmatter-required):

| Field | Required | Description |
|-------|----------|-------------|
| `name` | Yes | Max 64 chars. Lowercase a-z, 0-9, hyphens. Unlike the standard, OMK does not require this to match the parent directory because that standard requirement is suboptimal for shared skill directories. |
| `description` | Yes | Max 1024 chars. What the skill does and when to use it. |
| `license` | No | License name or reference to bundled file. |
| `compatibility` | No | Max 500 chars. Environment requirements. |
| `metadata` | No | Arbitrary key-value mapping. |
| `allowed-tools` | No | Space-delimited list of pre-approved tools (experimental). |
| `disable-model-invocation` | No | When `true`, skill is hidden from system prompt. Users must use `/skill:name` or `!skill:name`. |

### Name Rules

- 1-64 characters
- Lowercase letters, numbers, hyphens only
- No leading/trailing hyphens
- No consecutive hyphens
OMK does not require the name to match the parent directory. The Agent Skills standard does, but that requirement is suboptimal for shared skill directories used by multiple tools.

Valid: `pdf-processing`, `data-analysis`, `code-review`
Invalid: `PDF-Processing`, `-pdf`, `pdf--processing`

### Description Best Practices

The description determines when the agent loads the skill. Be specific.

Good:
```yaml
description: Extracts text and tables from PDF files, fills PDF forms, and merges multiple PDFs. Use when working with PDF documents.
```

Poor:
```yaml
description: Helps with PDFs.
```

## Validation

OMK validates skills against the Agent Skills standard. Most issues produce warnings but still load the skill:

- Name exceeds 64 characters or contains invalid characters
- Name starts/ends with hyphen or has consecutive hyphens
- Description exceeds 1024 characters

Unknown frontmatter fields are ignored.

**Exception:** Skills with missing description are not loaded.

Name collisions (same name from different locations) warn and keep the first skill found.

## Example

```
brave-search/
├── SKILL.md
├── search.js
└── content.js
```

**SKILL.md:**
````markdown
---
name: brave-search
description: Web search and content extraction via Brave Search API. Use for searching documentation, facts, or any web content.
---

# Brave Search

## Setup

```bash
cd /path/to/brave-search && npm install
```

## Search

```bash
./search.js "query"              # Basic search
./search.js "query" --content    # Include page content
```

## Extract Page Content

```bash
./content.js https://example.com
```
````

## Skill Repositories

- [Anthropic Skills](https://github.com/anthropics/skills) - Document processing (docx, pdf, pptx, xlsx), web development
- [OMK Skills](https://github.com/badlogic/omk-skills) - Web search, browser automation, Google APIs, transcription
