pi-mono/packages/coding-agent/docs/skills.md

pi 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.

Pi implements the Agent Skills standard, warning about most violations but remaining lenient. Pi 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
• How Skills Work
• Skill Commands
• Skill Structure
• Frontmatter
• Validation
• Example
• 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.

Pi loads skills from:

• Global:
  • ~/.pi/agent/skills/
  • ~/.agents/skills/
• Project:
  • .pi/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 pi.skills entries in package.json
• Settings: skills array with files or directories
• CLI: --skill <path> (repeatable, additive even with --no-skills)

Discovery rules:

• In ~/.pi/agent/skills/ and .pi/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:

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

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

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

How Skills Work

1. At startup, pi scans skill locations and extracts names and descriptions
2. The system prompt includes available skills in XML format per the specification
3. When a task matches, the agent uses read to load the full SKILL.md (models don't always do this; use prompting 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:

/skill:brave-search           # Load and execute the skill
/skill:pdf-tools extract      # Load skill with arguments

Arguments after the command are appended to the skill content as User: <args>.

Toggle skill commands via /settings in interactive mode or in settings.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

---
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:

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

Frontmatter

Per the Agent Skills specification:

Field	Required	Description
name	Yes	Max 64 chars. Lowercase a-z, 0-9, hyphens. Unlike the standard, Pi 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.

Name Rules

• 1-64 characters
• Lowercase letters, numbers, hyphens only
• No leading/trailing hyphens
• No consecutive hyphens Pi 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:

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

Poor:

description: Helps with PDFs.

Validation

Pi 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:

---
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 - Document processing (docx, pdf, pptx, xlsx), web development
• Pi Skills - Web search, browser automation, Google APIs, transcription