create-skill

name	create-skill
description	Guide creation of a new GAAI skill following the agentskills.io spec and GAAI best practices. Activate when adding a new skill to the .gaai/core/skills/ catalog.
license	MIT
compatibility	Works with any filesystem-based AI coding agent
metadata	{"author":"gaai-framework","version":"1.0","category":"cross","track":"cross-cutting","id":"SKILL-CRS-016","updated_at":"2026-02-26T00:00:00.000Z","status":"stable"}
inputs	[{"skill_intent":"description of what the skill should do"},{"skill_category":"discovery|delivery|cross"},{"skill_track":"discovery|delivery|cross-cutting"},{"existing_skills":"list of current skills to check for overlap"}]
outputs	[".gaai/core/skills/{category}/{skill-name}/SKILL.md","updated .gaai/core/skills/README.skills.md entry"]

Create Skill

Purpose / When to Activate

Activate when:

• A new capability is needed that no existing skill covers
• A skill is being extracted from agent logic that has become reusable
• Extending a forked GAAI installation with project-specific skills

This skill is self-referential: it uses the agentskills.io spec to author a spec-compliant skill.

---

Prerequisites

Before activating:

1. Confirm no existing skill already covers the intended capability (check README.skills.md)
2. Confirm the new skill is a pure execution unit — it executes, it does not reason
3. Confirm the skill belongs to exactly one category (discovery / delivery / cross)
4. Have a clear, one-sentence description of: WHAT it does and WHEN to activate it

If a skill "appears to think" in the design, it is wrongly scoped. Redesign or split.

---

Process

Step 1 — Name and classify

Derive the skill name from the action it performs:

• Use lowercase kebab-case
• Name should be a verb phrase: generate-stories, qa-review, memory-compact
• Category: discovery (produces artefacts) | delivery (implements/validates) | cross (shared utility)

Verify name does not conflict with an existing skill in README.skills.md.

Step 2 — Define inputs and outputs explicitly

List every input the skill requires. Be specific:

• What file paths does it read?
• What structured data does it receive from the invoking agent?
• What context is assumed to be present?

List every output the skill produces:

• File paths created or modified
• Structured data returned to the agent
• Side effects (backlog state changes, memory updates)

If inputs or outputs are unclear, the skill is not ready to be written. Clarify first.

Step 3 — Write the SKILL.md frontmatter

---
name: { skill-name } # matches directory name exactly
description: { one sentence } # WHAT it does + WHEN to activate
license: MIT
compatibility: Works with any filesystem-based AI coding agent
metadata:
  author: { author }
  version: "1.0"
  category: { discovery|delivery|cross }
  track: { discovery|delivery|cross-cutting }
  id: SKILL-{CAT}-{NNN}
  updated_at: { YYYY-MM-DD }
  status: stable|experimental # use experimental for new/unproven skills
inputs:
  - { input_1 }: { description }
  - { input_2 }: { description }
outputs:
  - { output_path_or_description }
---

Description rule: Must be one sentence, ≤ 1024 characters. Format:

"{Verb phrase that describes the output} when {activation condition}."

Example: "Generate Stories from an Epic with testable acceptance criteria when Discovery is refining a new feature scope."

Step 4 — Write the skill body

Required sections:

# {Skill Title}

## Purpose / When to Activate

When and why an agent should invoke this skill. Be explicit.

## Process

Numbered steps. Each step produces a specific output or advances the state.
Steps must be deterministic: same inputs → same outputs.

## Quality Checks

What must be true for the output to be acceptable.
List as assertions, not descriptions.

## Outputs

Exact file paths or structured outputs produced.

## Non-Goals

What this skill must NOT do. Prevents scope creep.

Add a final line if applicable:

No silent assumptions. Every {X} becomes explicit and governed.

Step 5 — Create directory and file

.gaai/core/skills/{category}/{skill-name}/SKILL.md

SKILL.md filename is always uppercase (spec requirement).

Optional subdirectories (create only if needed):

• references/ — supporting documents the skill references
• assets/ — templates or static files the skill produces

Step 6 — Update ALL relevant indices (MANDATORY)

This step is non-negotiable. A skill that is not indexed is invisible to agents.

6a. Skills index YAML:

• Invoke build-skills-index to regenerate both .gaai/core/skills/skills-index.yaml (core) and .gaai/project/skills/skills-index.yaml (project)
• Verify the new skill appears in the generated index with correct id, name, path, and tags

6b. Skills README:

• Core skills: update .gaai/core/skills/README.skills.md — add the skill to the appropriate category section
• Project skills: update .gaai/project/skills/README.md — add the skill to the appropriate section

6c. Domain index (if domain-scoped skill):

• If the skill belongs to a domain (e.g., domains/content-production/), update the domain's index.md in memory:
  • .gaai/project/contexts/memory/domains/{domain}/index.md — add a row to the skills table
• This ensures domain sub-agents discover the skill when loading their domain context

Failure to update any of these indices means the skill is effectively invisible — agents cannot discover it, and it will not be loaded during delivery or discovery sessions.

Step 7 — Reference in agent file

If the skill is intended for a specific agent (Discovery or Delivery), add it to the agent's skill list in:

• .gaai/core/agents/discovery.agent.md — Skills Used section
• .gaai/core/agents/delivery.agent.md — Skills Used section
• Or neither, if it's a general cross skill invoked opportunistically

---

Quality Checks

• Skill name matches directory name exactly
• SKILL.md frontmatter has name and description at top level (spec requirement)
• Description is ≤ 1024 characters, one sentence
• All inputs are explicitly declared
• All outputs are explicitly declared with file paths where applicable
• Skill body has all 5 required sections
• Non-Goals section explicitly prevents scope creep
• README.skills.md updated
• health-check.sh passes after creation

---

Non-Goals

This skill must NOT:

• Design agent behavior or orchestration logic (that is an agent concern)
• Make decisions about when to activate the skill (the invoking agent decides)
• Merge or replace an existing skill (deprecation requires explicit human decision)

A skill that appears to think is wrongly designed. Redesign before authoring.