<table>
<tr>
<td>
<img src="https://github.com/wkusnierczyk/aigent/raw/main/graphics/aigent.png" alt="logo" width="300" />
</td>
<td>
<p><strong><code>aigent</code></strong>:
A library, CLI tool, and Claude Code plugin for managing AI agent skill definitions.</p>
<p>Validates, parses, and generates prompts from skill metadata stored in <code>SKILL.md</code> files with YAML frontmatter. Also provides a skill builder for creating new skills from natural language specifications.</p>
</td>
</tr>
</table>
## Table of Contents
- [Installation](#installation)
- [Quick Start](#quick-start)
- [Library Usage](#library-usage)
- [SKILL.md Format](#skillmd-format)
- [Builder Modes](#builder-modes)
- [Compliance](#compliance)
- [CLI Reference](#cli-reference)
- [API Reference](#api-reference)
- [Claude Code Plugin](#claude-code-plugin)
- [Development](#development)
- [CI/CD and Release Workflows](#cicd-and-release-workflows)
- [References](#references)
- [About and Licence](#about-and-licence)
## Installation
### Prerequisites
- [Rust](https://www.rust-lang.org/tools/install) (stable toolchain)
- `cargo` (included with Rust)
### From crates.io
```bash
cargo install aigent
```
### From source
```bash
git clone https://github.com/wkusnierczyk/aigent.git
cd aigent
cargo install --path .
```
### Pre-built binaries
Download a pre-built binary from the
[latest release](https://github.com/wkusnierczyk/aigent/releases/latest)
(Linux x86_64/aarch64, macOS x86_64/aarch64, Windows x86_64).
### Install script (Linux and macOS)
```bash
## Quick Start
```bash
# Initialize a new skill
aigent init my-skill/
# Create a skill from a description
aigent new "Process PDF files and extract text" --no-llm
# Validate a skill directory (spec conformance)
aigent validate my-skill/ --structure
# Run validate + semantic quality checks
aigent check my-skill/
# Score a skill against best practices (0–100)
aigent score my-skill/
# Format a SKILL.md (canonical key order, clean whitespace)
aigent fmt my-skill/
# Probe skill activation against a query
aigent probe my-skill/ "process PDF files"
# Run fixture-based test suite
aigent test my-skill/
# Check for upgrade opportunities
aigent upgrade my-skill/
# Assemble skills into a Claude Code plugin
aigent build my-skill/ other-skill/ --output ./dist
# Generate a skill catalog
aigent doc skills/ --recursive
# Read skill properties as JSON
aigent read-properties my-skill/
# Generate XML prompt for LLM injection
aigent prompt my-skill/ other-skill/
```
To enable LLM-enhanced generation, set an API key in your environment
(for example, `export ANTHROPIC_API_KEY=sk-...`). Without an API key,
the builder uses deterministic mode, which requires no configuration.
See [Builder Modes](#builder-modes) for details.
## Library Usage
```rust
use std::path::Path;
// Validate a skill directory
let errors = aigent::validate(Path::new("my-skill"));
// Read skill properties
let props = aigent::read_properties(Path::new("my-skill")).unwrap();
// Generate prompt XML
let xml = aigent::to_prompt(&[Path::new("skill-a"), Path::new("skill-b")]);
// Format a SKILL.md
let result = aigent::format_skill(Path::new("my-skill")).unwrap();
// Assemble skills into a plugin
let opts = aigent::AssembleOptions {
output_dir: std::path::PathBuf::from("./dist"),
name: None,
validate: true,
};
let result = aigent::assemble_plugin(
&[Path::new("skill-a"), Path::new("skill-b")], &opts,
).unwrap();
// Build a skill
let spec = aigent::SkillSpec {
purpose: "Process PDF files".to_string(),
no_llm: true,
..Default::default()
};
let result = aigent::build_skill(&spec).unwrap();
```
## SKILL.md Format
Skills are defined in `SKILL.md` files with YAML frontmatter and a Markdown body:
```markdown
---
name: extract-csv-data
description: >-
Extract and transform data from CSV files. Use when the user needs
to parse, filter, or aggregate CSV data.
license: MIT
compatibility: claude
allowed-tools: Read, Write, Bash
---
# Extract CSV Data
Parse and transform CSV files into structured data.
## When to Use
Use this skill when:
- The user asks to extract data from CSV files
- The task involves filtering or aggregating tabular data
## Instructions
1. Read the CSV file using the Read tool
2. Parse the header row to identify columns
3. Apply any requested filters or transformations
```
### Frontmatter fields
| Field | Required | Description |
|-------|:--------:|-------------|
| `name` | yes | Kebab-case identifier (e.g., `extract-csv-data`) |
| `description` | yes | What the skill does and when to use it |
| `license` | no | Licence identifier (e.g., `MIT`) |
| `compatibility` | no | Compatible agent platforms |
| `allowed-tools` | no | Tools the skill may use |
### Validation rules
- `name` and `description` are required and non-empty
- `name`: lowercase letters, digits, and hyphens only; maximum 64 characters
- `name`: must not contain reserved words (`anthropic`, `claude`)
- `name`: no XML tags; must match directory name
- `name`: Unicode NFKC normalization applied before validation
- `description`: maximum 1024 characters; no XML/HTML tags
- `compatibility`: maximum 500 characters (if present)
- Body: warning if longer than 500 lines
## Builder Modes
The skill builder operates in two modes:
**Deterministic** — Always available, zero configuration. Uses heuristic
rules to derive skill names (gerund form, kebab-case), descriptions, and
Markdown bodies. Output is formulaic but valid.
**LLM-enhanced** — Auto-detected via environment variables. Produces
richer, more natural output. Each generation step (name, description, body)
independently falls back to deterministic on LLM failure.
### Provider detection order
| Priority | Environment Variable | Provider |
|:--------:|---------------------|----------|
| 1 | `ANTHROPIC_API_KEY` | Anthropic Claude |
| 2 | `OPENAI_API_KEY` | OpenAI |
| 3 | `GOOGLE_API_KEY` | Google Gemini |
| 4 | `OLLAMA_HOST` | Ollama (local) |
### Available models (as of 2026-02-20)
| Provider | Environment Variable | Default Model | Override Variable |
|----------|---------------------|---------------|-------------------|
| Anthropic | `ANTHROPIC_API_KEY` | `claude-sonnet-4-20250514` | `ANTHROPIC_MODEL` |
| OpenAI | `OPENAI_API_KEY` | `gpt-4o` | `OPENAI_MODEL` |
| Google | `GOOGLE_API_KEY` | `gemini-2.0-flash` | `GOOGLE_MODEL` |
| Ollama | `OLLAMA_HOST` | `llama3.2` | `OLLAMA_MODEL` |
OpenAI-compatible endpoints (vLLM, LM Studio, etc.) are supported via
`OPENAI_API_BASE` or `OPENAI_BASE_URL`.
Use `--no-llm` to force deterministic mode regardless of available providers.
## Compliance
### Specification Coverage
Three-way comparison of the
[Anthropic agent skill specification](https://platform.claude.com/docs/en/agents-and-tools/agent-skills/best-practices),
aigent, and the
[Python reference implementation](https://github.com/agentskills/agentskills).
> Table shows key validation rules from the Anthropic specification. Additional
> checks (frontmatter structure, metadata keys, YAML syntax) are implemented
> but not listed as they are standard parser behaviour.
| Rule | aigent | Specification | Python Reference |
|------|:------:|:-------------:|:----------------:|
| Name ≤ 64 characters | ✅ | ✅ | ✅ |
| Name: lowercase + hyphens | ✅ | ✅ | ✅ |
| Name: no XML tags | ✅ | ✅ | ❌ |
| Name: no reserved words | ✅ | ✅ | ❌ |
| Name: Unicode NFKC | ✅ | — | ❌ |
| Description: non-empty | ✅ | ✅ | ✅ |
| Description ≤ 1024 characters | ✅ | ✅ | ✅ |
| Description: no XML tags | ✅ | ✅ | ❌ |
| Frontmatter `---` delimiters | ✅ | ✅ | ✅ |
| Compatibility ≤ 500 characters | ✅ | ✅ | ❌ |
| Body ≤ 500 lines warning | ✅ | ✅ | ❌ |
| Prompt XML format | ✅ | ✅ | ✅ |
| Path canonicalization | ✅ | — | ✅ |
| Post-build validation | ✅ | — | ❌ |
aigent implements **all** rules from the specification, plus additional checks
(Unicode NFKC normalization, path canonicalization, post-build validation) that
go beyond both the specification and the reference implementation.
### aigent vs. plugin-dev
Anthropic's **plugin-dev** plugin (bundled with Claude Code) and **aigent**
are complementary tools for skill development:
| | **aigent** | **plugin-dev** |
|---|---|---|
| **What** | Rust CLI + library | Claude Code plugin (LLM-guided) |
| **Scope** | Deep: SKILL.md toolchain | Broad: entire plugin ecosystem |
| **Validation** | Deterministic — typed diagnostics, error codes, JSON output | Heuristic — agent-based review |
| **Scoring** | Weighted 0–100 with CI gating | Not available |
| **Formatting** | `aigent fmt` — idempotent, `--check` for CI | Not available |
| **Testing** | Fixture-based (`tests.yml`) + single-query probe | General guidance only |
| **Assembly** | `aigent build` — reproducible, scriptable | `/create-plugin` — guided, interactive |
| **Ecosystem** | Skills only | Skills + commands + agents + hooks + MCP + settings |
aigent handles the **depth** of SKILL.md quality enforcement (validation,
scoring, formatting, testing, assembly). plugin-dev covers the **breadth**
of the Claude Code plugin ecosystem (7 component types, ~21,000 words of
guidance). Use plugin-dev to learn patterns; use aigent to enforce them.
For the full analysis, see [dev/plugin-dev.md](dev/plugin-dev.md).
### Extras
Features in aigent that go beyond the specification and reference implementation:
| Feature | Description |
|---------|-------------|
| Semantic linting | Quality checks: third-person descriptions, trigger phrases, gerund names, generic names |
| Quality scoring | Weighted 0–100 score with distinct pass/fail labels per check |
| Auto-fix | Automatic correction of fixable issues (e.g., name casing) |
| Skill builder | Generate skills from natural language (deterministic + multi-provider LLM) |
| Interactive build | Step-by-step confirmation mode for skill generation |
| Skill tester (probe) | Simulate skill activation with weighted scoring formula (0.5×description + 0.3×trigger + 0.2×name) |
| Fixture-based testing | Run test suites from `tests.yml` with expected match/no-match and minimum score thresholds |
| SKILL.md formatter | Canonical YAML key ordering, consistent whitespace, idempotent formatting |
| Skill-to-plugin assembly | Package skill directories into a Claude Code plugin with `plugin.json` manifest |
| Skill upgrade | Detect and apply best-practice upgrades with `--full` mode (validate + lint + fix + upgrade) |
| Unified check command | `check` = validate + semantic lint; `--no-validate` for lint-only |
| Directory structure validation | Check for missing references, script permissions, nesting depth |
| Cross-skill conflict detection | Name collisions, description similarity, token budget analysis |
| Documentation generation | Markdown skill catalog with diff-aware output |
| Watch mode | Continuous validation on filesystem changes (optional `notify` feature) |
| Multi-format prompt output | XML, JSON, YAML, Markdown prompt generation |
| Multi-format validation output | Text and JSON diagnostic output |
| Token budget estimation | Per-skill and total token usage reporting |
| Claude Code plugin | Hybrid skills that work with or without the CLI installed |
## CLI Reference
Run `aigent --help` for a list of commands, or `aigent <command> --help` for
details on a specific command (flags, arguments, examples). Full API
documentation is available at [docs.rs/aigent](https://docs.rs/aigent).
### Commands
**Quality spectrum:** `validate` (spec conformance) → `check` (+ semantic quality) → `score` (quantitative 0–100).
<table>
<tr><th width="280">Command</th><th>Description</th></tr>
<tr><td><code>validate <dirs...></code></td><td>Validate skill directories against the spec; exit 0 if valid</td></tr>
<tr><td><code>check <dirs...></code></td><td>Run validate + semantic lint checks (superset of <code>validate</code>)</td></tr>
<tr><td><code>score <directory></code></td><td>Score a skill against best-practices checklist (0–100)</td></tr>
<tr><td><code>fmt <dirs...></code></td><td>Format SKILL.md files (canonical key order, clean whitespace)</td></tr>
<tr><td><code>probe <directory> <query></code></td><td>Probe skill activation against a sample user query</td></tr>
<tr><td><code>test <dirs...></code></td><td>Run fixture-based test suites from <code>tests.yml</code></td></tr>
<tr><td><code>upgrade <directory></code></td><td>Check a skill for upgrade opportunities</td></tr>
<tr><td><code>build <dirs...></code></td><td>Assemble skills into a Claude Code plugin</td></tr>
<tr><td><code>new <purpose></code></td><td>Create a skill from natural language</td></tr>
<tr><td><code>init [directory]</code></td><td>Create a template SKILL.md</td></tr>
<tr><td><code>doc <dirs...></code></td><td>Generate a markdown skill catalog</td></tr>
<tr><td><code>read-properties <directory></code></td><td>Output skill properties as JSON</td></tr>
<tr><td><code>prompt <dirs...></code></td><td>Generate <code><available_skills></code> XML block</td></tr>
</table>
> **Backward compatibility:** The old command names `lint`, `to-prompt`, and `create` are
> available as hidden aliases and continue to work. The old `test <dir> <query>` single-query
> syntax has been renamed to `probe`; `test` now runs fixture-based test suites.
### Validate Flags
<table>
<tr><th width="280">Flag</th><th>Description</th></tr>
<tr><td><code>--structure</code></td><td>Run directory structure checks</td></tr>
<tr><td><code>--recursive</code></td><td>Discover skills recursively</td></tr>
<tr><td><code>--apply-fixes</code></td><td>Apply automatic fixes for fixable issues</td></tr>
<tr><td><code>--watch</code></td><td>Watch for changes and re-validate (see <a href="#watch-mode">Watch mode</a>)</td></tr>
<tr><td><code>--target <TARGET></code></td><td>Validation target: <code>standard</code>, <code>claude-code</code>, or <code>permissive</code></td></tr>
<tr><td><code>--format <FORMAT></code></td><td>Output format: <code>text</code> or <code>json</code></td></tr>
</table>
> **Note:** Semantic lint checks have moved to `check`. Use `aigent check` for
> combined validation + linting, or `aigent check --no-validate` for lint-only.
### Check Flags
<table>
<tr><th width="280">Flag</th><th>Description</th></tr>
<tr><td><code>--no-validate</code></td><td>Skip spec conformance checks (semantic quality only)</td></tr>
<tr><td><code>--structure</code></td><td>Run directory structure checks</td></tr>
<tr><td><code>--recursive</code></td><td>Discover skills recursively</td></tr>
<tr><td><code>--apply-fixes</code></td><td>Apply automatic fixes for fixable issues</td></tr>
<tr><td><code>--target <TARGET></code></td><td>Validation target: <code>standard</code>, <code>claude-code</code>, or <code>permissive</code></td></tr>
<tr><td><code>--format <FORMAT></code></td><td>Output format: <code>text</code> or <code>json</code></td></tr>
</table>
### New Flags
<table>
<tr><th width="280">Flag</th><th>Description</th></tr>
<tr><td><code>--name <NAME></code></td><td>Override the derived skill name</td></tr>
<tr><td><code>--dir <DIRECTORY></code></td><td>Output directory</td></tr>
<tr><td><code>--no-llm</code></td><td>Force deterministic mode (no LLM)</td></tr>
<tr><td><code>--interactive, -i</code></td><td>Step-by-step confirmation mode</td></tr>
</table>
### Fmt Flags
<table>
<tr><th width="280">Flag</th><th>Description</th></tr>
<tr><td><code>--check</code></td><td>Check formatting without modifying files (exit 1 if unformatted)</td></tr>
<tr><td><code>--recursive</code></td><td>Discover skills recursively</td></tr>
</table>
### Build (Assembly) Flags
<table>
<tr><th width="280">Flag</th><th>Description</th></tr>
<tr><td><code>--output <DIR></code></td><td>Output directory for the assembled plugin (default: <code>./dist</code>)</td></tr>
<tr><td><code>--name <NAME></code></td><td>Override the plugin name (default: first skill name)</td></tr>
<tr><td><code>--validate</code></td><td>Run validation on assembled skills</td></tr>
</table>
### Test Flags
<table>
<tr><th width="280">Flag</th><th>Description</th></tr>
<tr><td><code>--generate</code></td><td>Generate a starter <code>tests.yml</code> for skills that lack one</td></tr>
<tr><td><code>--recursive</code></td><td>Discover skills recursively</td></tr>
<tr><td><code>--format <FORMAT></code></td><td>Output format: <code>text</code> or <code>json</code></td></tr>
</table>
### Upgrade Flags
<table>
<tr><th width="280">Flag</th><th>Description</th></tr>
<tr><td><code>--apply</code></td><td>Apply automatic upgrades</td></tr>
<tr><td><code>--full</code></td><td>Run validate + lint before upgrade (with <code>--apply</code>, also fix errors first)</td></tr>
<tr><td><code>--format <FORMAT></code></td><td>Output format: <code>text</code> or <code>json</code></td></tr>
</table>
### Command Examples
#### `validate` — Check skill directories for spec conformance
Validates one or more skill directories against the Anthropic specification.
Exit code 0 means valid; non-zero means errors or warnings were found. For
combined validation + semantic quality checks, use `check` instead.
```
$ aigent validate my-skill/
(no output — skill is valid)
```
With `--structure` for directory layout checks:
```
$ aigent validate skills/aigent-validator --structure
warning: unexpected metadata field: 'argument-hint'
```
Multiple directories trigger cross-skill conflict detection automatically:
```
$ aigent validate skills/aigent-validator skills/aigent-builder skills/aigent-scorer
skills/aigent-validator:
warning: unexpected metadata field: 'argument-hint'
skills/aigent-builder:
warning: unexpected metadata field: 'argument-hint'
warning: unexpected metadata field: 'context'
skills/aigent-scorer:
warning: unexpected metadata field: 'argument-hint'
3 skills: 0 ok, 0 errors, 3 warnings only
```
JSON output for CI integration:
```
$ aigent validate skills/aigent-validator --format json
[
{
"diagnostics": [
{
"code": "W001",
"field": "metadata",
"message": "unexpected metadata field: 'argument-hint'",
"severity": "warning"
}
],
"path": "skills/aigent-validator"
}
]
```
#### `check` — Validate + semantic quality checks
Runs spec conformance (like `validate`) plus semantic quality checks:
third-person descriptions, trigger phrases, gerund name forms, generic
names, and description detail. Use `--no-validate` to skip spec checks
and run semantic lint only.
```
$ aigent check skills/aigent-validator
warning: unexpected metadata field: 'argument-hint'
info: name does not use gerund form
```
Semantic lint only (equivalent to the old `lint` command):
```
$ aigent check --no-validate skills/aigent-validator
info: name does not use gerund form
```
#### `score` — Rate a skill 0–100
Rates a skill from 0 to 100 against the Anthropic best-practices checklist.
The score has two weighted categories:
- **Structural (60 points)** — Checks that the SKILL.md parses correctly, the
name matches the directory, required fields are present, no unknown fields
exist, and the body is within size limits. All six checks must pass to earn
the 60 points; any failure zeros the structural score.
- **Quality (40 points)** — Five semantic lint checks worth 8 points each:
third-person description, trigger phrase (`"Use when..."`), gerund name form
(`converting-pdfs` not `pdf-converter`), specific (non-generic) name, and
description length (≥ 20 words).
The exit code is 0 for a perfect score and 1 otherwise, making it suitable for
CI gating.
**Example** — a skill that passes all checks:
```
$ aigent score converting-pdfs/
Score: 100/100
Structural (60/60):
[PASS] SKILL.md exists and is parseable
[PASS] Name format valid
[PASS] Description valid
[PASS] Required fields present
[PASS] No unknown fields
[PASS] Body within size limits
Quality (40/40):
[PASS] Third-person description
[PASS] Trigger phrase present
[PASS] Gerund name form
[PASS] Specific name
[PASS] Detailed description
```
**Example** — a skill with issues. Each check shows a distinct label for its
pass/fail state (e.g., "No unknown fields" when passing, "Unknown fields
found" when failing):
```
$ aigent score aigent-validator/
Score: 32/100
Structural (0/60):
[PASS] SKILL.md exists and is parseable
[PASS] Name format valid
[PASS] Description valid
[PASS] Required fields present
[FAIL] Unknown fields found
unexpected metadata field: 'argument-hint'
[PASS] Body within size limits
Quality (32/40):
[PASS] Third-person description
[PASS] Trigger phrase present
[FAIL] Non-gerund name form
name does not use gerund form
[PASS] Specific name
[PASS] Detailed description
```
#### `probe` — Simulate skill activation
Probes whether a skill's description would activate for a given user query.
This is a dry-run of skill discovery — "if a user said *this*, would Claude
pick up *that* skill?"
Uses a **weighted formula** to compute a match score (0.0–1.0):
- **0.5 × description overlap** — fraction of query tokens in description
- **0.3 × trigger score** — match against trigger phrases ("Use when...")
- **0.2 × name score** — query-to-name token overlap
Categories based on weighted score:
- **Strong** (≥ 0.4) — skill would reliably activate
- **Weak** (≥ 0.15) — might activate, but description could be improved
- **None** (< 0.15) — skill would not activate for this query
Also reports estimated token cost and any validation issues.
```
$ aigent probe skills/aigent-validator "validate a skill"
Skill: aigent-validator
Query: "validate a skill"
Description: Validates AI agent skill definitions (SKILL.md files) against
the Anthropic agent skill specification. ...
Activation: STRONG ✓ — description aligns well with query (score: 0.65)
Token footprint: ~76 tokens
Validation warnings (1):
warning: unexpected metadata field: 'argument-hint'
```
```
$ aigent probe skills/aigent-validator "deploy kubernetes"
...
Activation: NONE ✗ — description does not match the test query (score: 0.00)
Token footprint: ~76 tokens
```
#### `upgrade` — Detect and apply best-practice improvements
Checks for recommended-but-optional fields and patterns. Use `--apply` to
write missing fields into the SKILL.md. The `--full` flag first runs
validate + lint and optionally fixes errors before analysing upgrades.
```
$ aigent upgrade skills/aigent-validator
Missing 'compatibility' field — recommended for multi-platform skills.
Missing 'metadata.version' — recommended for tracking skill versions.
Missing 'metadata.author' — recommended for attribution.
Run with --apply to apply 3 suggestion(s).
```
```
$ aigent upgrade --apply skills/aigent-validator
(applies missing fields in-place, prints confirmation to stderr)
```
Full mode runs validate + lint first, and with `--apply` fixes errors
before performing upgrades:
```
$ aigent upgrade --full --apply skills/aigent-validator
[full] Applied 1 validation/lint fix(es)
Missing 'compatibility' field — recommended for multi-platform skills.
```
#### `doc` — Generate a skill catalog
Produces a markdown catalog of skills. Use `--recursive` to discover skills
in subdirectories, and `--output` to write to a file (diff-aware — only
writes if content changed).
```
$ aigent doc skills --recursive
# Skill Catalog
## aigent-builder
> Generates AI agent skill definitions (SKILL.md files) from natural
> language descriptions. ...
**Location**: `skills/aigent-builder/SKILL.md`
---
## aigent-scorer
> Scores AI agent skill definitions (SKILL.md files) against the Anthropic
> best-practices checklist. ...
**Location**: `skills/aigent-scorer/SKILL.md`
---
## aigent-validator
> Validates AI agent skill definitions (SKILL.md files) against the
> Anthropic agent skill specification. ...
**Location**: `skills/aigent-validator/SKILL.md`
---
```
```
$ aigent doc skills --recursive --output catalog.md
(writes catalog.md; re-running skips write if content unchanged)
```
#### `read-properties` — Output skill metadata as JSON
Parses the SKILL.md frontmatter and outputs structured JSON. Useful for
scripting and integration with other tools.
```
$ aigent read-properties skills/aigent-validator
{
"name": "aigent-validator",
"description": "Validates AI agent skill definitions ...",
"allowed-tools": "Bash(aigent validate *), Bash(command -v *), Read, Glob",
"metadata": {
"argument-hint": "[skill-directory-or-file]"
}
}
```
#### `prompt` — Generate XML prompt block
Generates the `<available_skills>` XML block that gets injected into Claude's
system prompt. Accepts multiple skill directories.
```
$ aigent prompt skills/aigent-validator
<available_skills>
<skill>
<name>aigent-validator</name>
<description>Validates AI agent skill definitions ...</description>
<location>skills/aigent-validator/SKILL.md</location>
</skill>
</available_skills>
```
#### `new` — Create a skill from natural language
Creates a complete skill directory with SKILL.md from a purpose description.
Uses LLM when an API key is available, or `--no-llm` for deterministic mode.
```
$ aigent new "Extract text from PDF files" --no-llm
Created skill 'extracting-text-pdf-files' at extracting-text-pdf-files
```
The generated SKILL.md includes derived name, description, and a starter body:
```markdown
---
name: extracting-text-pdf-files
description: Extract text from PDF files. Use when working with files.
---
# Extracting Text Pdf Files
## Quick start
Extract text from PDF files
## Usage
Use this skill to Extract text from PDF files.
```
#### `fmt` — Format SKILL.md files
Normalizes SKILL.md files with canonical YAML key ordering, consistent
whitespace, and clean formatting. The operation is idempotent — running
it twice produces no further changes.
```
$ aigent fmt my-skill/
Formatted my-skill/
```
Check mode reports which files would change without modifying them:
```
$ aigent fmt --check my-skill/
Would reformat: my-skill/
```
#### `build` — Assemble skills into a plugin
Packages one or more skill directories into a Claude Code plugin directory
with a `plugin.json` manifest, `skills/` subdirectory, and scaffolded
`agents/` and `hooks/` directories.
```
$ aigent build skills/aigent-validator skills/aigent-scorer --output ./dist
Assembled 2 skill(s) into ./dist
```
The output structure:
```
dist/
├── plugin.json
├── skills/
│ ├── aigent-validator/
│ │ └── SKILL.md
│ └── aigent-scorer/
│ └── SKILL.md
├── agents/
└── hooks/
```
#### `test` — Run fixture-based test suites
Runs test suites defined in `tests.yml` files alongside skills. Each test
case specifies an input query, whether it should match, and an optional
minimum score threshold.
Generate a starter `tests.yml`:
```
$ aigent test --generate my-skill/
Generated my-skill/tests.yml
```
Run the test suite:
```
$ aigent test my-skill/
[PASS] "process pdf files" (score: 0.65)
[PASS] "something completely unrelated to this skill" (score: 0.00)
2 passed, 0 failed, 2 total
```
#### `init` — Create a template SKILL.md
Scaffolds a skill directory with a template SKILL.md ready for editing.
```
$ aigent init my-skill
Created my-skill/SKILL.md
```
```
$ cat my-skill/SKILL.md
---
name: my-skill
description: Describe what this skill does and when to use it
---
# My Skill
## Quick start
[Add quick start instructions here]
## Usage
[Add detailed usage instructions here]
```
### Watch mode
The `--watch` flag on `validate` monitors skill directories for filesystem
changes and re-validates automatically on each edit — a live feedback loop
while developing skills.
Watch mode is behind a **Cargo feature gate** because it pulls in
platform-specific filesystem notification libraries (`notify`, `fsevent-sys`
on macOS, `inotify` on Linux). Without the feature, the binary is smaller
and has fewer dependencies.
**Building with watch mode:**
```bash
# Build with watch support
cargo build --release --features watch
# Run with watch support (--features must be passed every time)
cargo run --release --features watch -- validate --watch skills/
# Or install with watch support
cargo install aigent --features watch
```
> **Note:** Cargo feature flags are per-invocation — they are not remembered
> between builds. You must pass `--features watch` on every `cargo build` or
> `cargo run` invocation. Building debug with `--features watch` does not
> enable it for release builds, and vice versa.
Without the `watch` feature, using `--watch` prints a helpful error:
```
$ aigent validate --watch my-skill/
Watch mode requires the 'watch' feature. Rebuild with: cargo build --features watch
```
### Global Flags
<table>
<tr><th width="280">Flag</th><th>Description</th></tr>
<tr><td><code>--about</code></td><td>Show project information</td></tr>
<tr><td><code>--version</code></td><td>Print version</td></tr>
<tr><td><code>--help</code></td><td>Print help</td></tr>
</table>
## API Reference
Full Rust API documentation with examples is published at
[docs.rs/aigent](https://docs.rs/aigent).
### Types
| `SkillProperties` | `models` | Parsed skill metadata (name, description, licence, compatibility, allowed-tools) |
| `SkillSpec` | `builder` | Input specification for skill generation (purpose, optional overrides) |
| `BuildResult` | `builder` | Build output (properties, files written, output directory) |
| `ClarityAssessment` | `builder` | Purpose clarity evaluation result (clear flag, follow-up questions) |
| `Diagnostic` | `diagnostics` | Structured diagnostic with severity, code, message, field, suggestion |
| `ScoreResult` | `scorer` | Quality score result with structural and semantic categories |
| `TestResult` | `tester` | Skill activation probe result (query match, score, diagnostics, token cost) |
| `TestSuiteResult` | `test_runner` | Fixture-based test suite result (passed, failed, per-case results) |
| `FormatResult` | `formatter` | SKILL.md formatting result (changed flag, formatted content) |
| `AssembleOptions` | `assembler` | Options for skill-to-plugin assembly (output dir, name, validate) |
| `AssembleResult` | `assembler` | Assembly output (plugin directory, skill count) |
| `SkillEntry` | `prompt` | Collected skill entry for prompt generation (name, description, location) |
| `AigentError` | `errors` | Error enum: `Parse`, `Validation`, `Build`, `Io`, `Yaml` |
| `Result<T>` | `errors` | Convenience alias for `std::result::Result<T, AigentError>` |
### Functions
| `validate(&Path) -> Vec<Diagnostic>` | `validator` | Validate skill directory |
| `validate_with_target(&Path, ValidationTarget)` | `validator` | Validate with target profile |
| `read_properties(&Path) -> Result<SkillProperties>` | `parser` | Parse directory into `SkillProperties` |
| `find_skill_md(&Path) -> Option<PathBuf>` | `parser` | Find `SKILL.md` in directory (prefers uppercase) |
| `parse_frontmatter(&str) -> Result<(HashMap, String)>` | `parser` | Split YAML frontmatter and body |
| `to_prompt(&[&Path]) -> String` | `prompt` | Generate `<available_skills>` XML system prompt |
| `to_prompt_format(&[&Path], PromptFormat) -> String` | `prompt` | Generate prompt in specified format |
| `lint(&SkillProperties, &str) -> Vec<Diagnostic>` | `linter` | Run semantic quality checks |
| `score(&Path) -> ScoreResult` | `scorer` | Score skill against best-practices checklist |
| `test_skill(&Path, &str) -> Result<TestResult>` | `tester` | Probe skill activation against a query |
| `format_skill(&Path) -> Result<FormatResult>` | `formatter` | Format SKILL.md with canonical key order |
| `format_content(&str) -> Result<String>` | `formatter` | Format SKILL.md content string |
| `assemble_plugin(&[&Path], &AssembleOptions) -> Result<AssembleResult>` | `assembler` | Assemble skills into a plugin |
| `run_test_suite(&Path) -> Result<TestSuiteResult>` | `test_runner` | Run fixture-based test suite |
| `generate_fixture(&Path) -> Result<String>` | `test_runner` | Generate starter `tests.yml` from skill metadata |
| `validate_structure(&Path) -> Vec<Diagnostic>` | `structure` | Validate directory structure |
| `detect_conflicts(&[SkillEntry]) -> Vec<Diagnostic>` | `conflict` | Detect cross-skill conflicts |
| `apply_fixes(&Path, &[Diagnostic]) -> Result<usize>` | `fixer` | Apply automatic fixes |
| `build_skill(&SkillSpec) -> Result<BuildResult>` | `builder` | Full build pipeline with post-build validation |
| `derive_name(&str) -> String` | `builder` | Derive kebab-case name from purpose (deterministic) |
| `assess_clarity(&str) -> ClarityAssessment` | `builder` | Evaluate if purpose is clear enough for generation |
| `init_skill(&Path, SkillTemplate) -> Result<PathBuf>` | `builder` | Initialize skill directory with template SKILL.md |
### Traits
| `LlmProvider` | `builder::llm` | Text generation provider interface (`generate(system, user) -> Result<String>`) |
## Claude Code Plugin
This repository is a
[Claude Code plugin](https://docs.anthropic.com/en/docs/agents-and-tools/claude-code/extensions#custom-slash-commands).
It provides three skills that Claude can use to build, validate, and score
SKILL.md files interactively.
### Skills
| `aigent-builder` | Generates skill definitions from natural language. Triggered by "create a skill", "build a skill", etc. |
| `aigent-validator` | Validates skills against the Anthropic specification. Triggered by "validate a skill", "check a skill", etc. |
| `aigent-scorer` | Scores skills against best-practices checklist. Triggered by "score a skill", "rate a skill", etc. |
All skills operate in **hybrid mode**: they use the `aigent` CLI when it is
installed, and fall back to Claude-based generation/validation when it is not.
This means the plugin works out of the box — no installation required — but
produces higher-quality results with `aigent` available.
### Plugin installation
To use the plugin in Claude Code, add it to your project's
`.claude/settings.json`:
```json
{
"permissions": {
"allow": []
},
"plugins": [
"wkusnierczyk/aigent"
]
}
```
## Development
### Prerequisites
- [Rust](https://www.rust-lang.org/tools/install) (stable toolchain)
- `cargo` (included with Rust)
### Setup
```bash
git clone https://github.com/wkusnierczyk/aigent.git
cd aigent
cargo build
```
### Optional tooling
```bash
cargo install cargo-edit # Adds `cargo set-version` for release versioning
```
### Common tasks
```bash
cargo build # Build (debug)
cargo build --release # Build (release)
cargo test # Run all tests
cargo clippy -- -D warnings # Lint (warnings as errors)
cargo fmt # Format code
cargo fmt --check # Check formatting
```
### Project structure
```
src/
├── lib.rs # Library root — re-exports public API
├── errors.rs # Error types (thiserror)
├── models.rs # SkillProperties (serde)
├── parser.rs # SKILL.md frontmatter parser (serde_yaml_ng)
├── validator.rs # Metadata and directory validator
├── linter.rs # Semantic lint checks
├── fixer.rs # Auto-fix for fixable diagnostics
├── diagnostics.rs # Structured diagnostics with error codes
├── prompt.rs # Multi-format prompt generation
├── scorer.rs # Quality scoring with pass/fail labels (0–100)
├── structure.rs # Directory structure validation
├── conflict.rs # Cross-skill conflict detection
├── tester.rs # Skill activation probe with weighted scoring
├── formatter.rs # SKILL.md formatting (canonical key order, whitespace)
├── assembler.rs # Skill-to-plugin assembly
├── test_runner.rs # Fixture-based testing (tests.yml)
├── main.rs # CLI entry point (clap)
└── builder/
├── mod.rs # Build pipeline orchestration
├── deterministic.rs # Heuristic name/description/body generation
├── llm.rs # LLM provider trait and generation functions
├── template.rs # Template for init command
├── util.rs # Internal utilities
└── providers/
├── mod.rs # Provider module declarations
├── anthropic.rs # Anthropic Claude API
├── openai.rs # OpenAI (and compatible) API
├── google.rs # Google Gemini API
└── ollama.rs # Ollama local API
```
### Versioning
Version is stored in `Cargo.toml` (single source of truth) and read at compile
time via `env!("CARGO_PKG_VERSION")`.
### Milestones
**Status:** Implementation complete (M1–M13). In review.
Project tracked at
[github.com/users/wkusnierczyk/projects/39](https://github.com/users/wkusnierczyk/projects/39).
| M1 | Project Scaffolding | ✅ |
| M2 | Errors and Models | ✅ |
| M3 | Parser | ✅ |
| M4 | Validator | ✅ |
| M5 | Prompt | ✅ |
| M6 | CLI | ✅ |
| M7 | Builder | ✅ |
| M8 | Main Module and Documentation | ✅ |
| M9 | Claude Code Plugin | ✅ |
| M10 | Improvements and Extensions | ✅ |
| M11 | Builder and Prompt Enhancements | ✅ |
| M12 | Ecosystem and Workflow | ✅ |
| M13 | Enhancements | ✅ |
| M14 | SRE Review | 🔲 |
| M15 | Plugin Ecosystem Validation | 🔲 |
### Roadmap
**M14: SRE Review** — security, reliability, and performance hardening prior
to publication. Addresses symlink following, path traversal, uncapped file
reads, silent error swallowing, TOCTOU races, and O(n²) conflict detection.
10 issues ([#87](https://github.com/wkusnierczyk/aigent/issues/87)–[#96](https://github.com/wkusnierczyk/aigent/issues/96)).
**M15: Plugin Ecosystem Validation** — extend aigent's deterministic
validation from SKILL.md to the full Claude Code plugin ecosystem.
Complements [plugin-dev](dev/plugin-dev.md) by mechanizing the rules it
teaches through prose and LLM-driven agents:
- Hook validation (`hooks.json`) — replaces plugin-dev's `validate-hook-schema.sh`
- Agent file validation (`.md` frontmatter) — replaces plugin-dev's `validate-agent.sh`
- Plugin manifest validation (`plugin.json`) — mechanizes `plugin-validator` agent checks
- Command file validation (`.md` frontmatter) — first deterministic validator for commands
- Cross-component consistency checks — unique to aigent, no plugin-dev equivalent
5 issues ([#97](https://github.com/wkusnierczyk/aigent/issues/97)–[#101](https://github.com/wkusnierczyk/aigent/issues/101)).
See [dev/plugin-dev.md](dev/plugin-dev.md) for the full analysis.
## CI/CD and Release Workflows
### Continuous integration
Every push to `main` and every pull request runs the CI pipeline on a
**three-OS matrix** (Ubuntu, macOS, Windows):
1. **Formatting** — `cargo fmt --check`
2. **Linting** — `cargo clippy -- -D warnings`
3. **Testing** — `cargo test`
4. **Release build** — `cargo build --release`
### Release workflow
Pushing a version tag (e.g., `v0.1.0`) triggers the release workflow:
1. **Test** — full test suite on Ubuntu
2. **Build** — cross-compile for five targets:
- `x86_64-unknown-linux-gnu`
- `aarch64-unknown-linux-gnu` (via `cross`)
- `x86_64-apple-darwin`
- `aarch64-apple-darwin`
- `x86_64-pc-windows-msvc`
3. **Release** — create GitHub Release with changelog and binary assets
4. **Publish** — publish to [crates.io](https://crates.io/crates/aigent)
## References
| [Anthropic agent skill specification](https://platform.claude.com/docs/en/agents-and-tools/agent-skills/best-practices) | Official specification for SKILL.md format and validation rules |
| [Agent Skills organisation](https://github.com/agentskills) | Umbrella for agent skills tooling |
| [agentskills/agentskills](https://github.com/agentskills/agentskills) | Python reference implementation |
| [anthropics/skills](https://github.com/anthropics/skills) | Anthropic's skills repository |
| [docs.rs/aigent](https://docs.rs/aigent) | Rust API documentation |
| [crates.io/crates/aigent](https://crates.io/crates/aigent) | Package registry |
## About and Licence
```
aigent: Rust AI Agent Skills Tool
├─ version: 0.4.0
├─ author: Wacław Kuśnierczyk
├─ developer: mailto:waclaw.kusnierczyk@gmail.com
├─ source: https://github.com/wkusnierczyk/aigent
└─ licence: MIT https://opensource.org/licenses/MIT
```
[MIT](LICENSE) — see [opensource.org/licenses/MIT](https://opensource.org/licenses/MIT).