BuilderIO/create-skill

Create a Skill

When to Use

Create a new skill when:

• There's a pattern the agent should follow repeatedly
• A workflow needs step-by-step guidance
• You want to scaffold files from a template

Don't create a skill when:

• The guidance already exists in another skill (extend it instead)
• You're documenting something the agent already knows (e.g., how to write TypeScript)
• The guidance is a one-off — put it in AGENTS.md or learnings.md instead

5-Question Interview

Before writing the skill, answer these:

1. What should this skill enable? — The core purpose in one sentence.
2. Which agent-native rule does it serve? — Rule 1 (files), Rule 2 (delegate), Rule 3 (scripts), Rule 4 (SSE), Rule 5 (self-modify), or "utility."
3. When should it trigger? — Describe the situations in natural language. Be slightly pushy — over-triggering is better than under-triggering.
4. What type of skill? — Pattern, Workflow, or Generator (see templates below).
5. Does it need supporting files? — References (read-only context) or none. Keep it minimal.

Skill Types and Templates

Pattern (architectural rule)

For documenting how things should be done:

---
name: my-pattern
description: >-
  [Under 40 words. When should this trigger?]
---

# [Pattern Name]

## Rule

[One sentence: what must be true]

## Why

[Why this rule exists]

## How

[How to follow it, with code examples]

## Don't

[Common violations]

## Related Skills

[Which skills compose with this one]

Workflow (step-by-step)

For multi-step implementation tasks:

---
name: my-workflow
description: >-
  [Under 40 words. When should this trigger?]
---

# [Workflow Name]

## Prerequisites

[What must be in place first]

## Steps

[Numbered steps with code examples]

## Verification

[How to confirm it worked]

## Troubleshooting

[Common issues and fixes]

## Related Skills

Generator (scaffolding)

For creating files from templates:

---
name: my-generator
description: >-
  [Under 40 words. When should this trigger?]
---

# [Generator Name]

## Usage

[How to invoke — what args/inputs are needed]

## What Gets Created

[List of files and their purpose]

## Template

[The template content with placeholders]

## After Generation

[What to do next — wire up SSE, add routes, etc.]

## Related Skills

Naming Conventions

• Hyphen-case only: [a-z0-9-], max 64 characters
• Pattern skills: descriptive names (storing-data, delegate-to-agent)
• Workflow/generator skills: verb-noun (create-script, capture-learnings)

Tips

• Keep descriptions under 40 words — They're loaded into context on every conversation.
• Keep SKILL.md under 500 lines — Move detailed content to references/ files.
• Use standard markdown headings — No XML tags or custom formats.

Anti-Patterns

• Inline LLM calls — Skills must not call LLMs directly (violates Rule 2)
• Database patterns — Skills must not introduce databases (violates Rule 1)
• Ignoring db sync — If a skill creates data, mention wiring up useDbSync
• Vague descriptions — "Helps with development" won't trigger. Be specific about when.
• Pure documentation — Skills should guide action, not just explain concepts

File Structure

.agents/skills/my-skill/
├── SKILL.md              # Main skill (required)
└── references/           # Optional supporting context
    └── detailed-guide.md

Related Skills

• capture-learnings — When a learning graduates to reusable guidance, create a skill
• self-modifying-code — The agent can create new skills (Tier 2 modification)