Antigravity skill creator

AntiGravity Skill Creator

Creates skills compatible with the AntiGravity agent environment (.agent/skills/) following the Agent Skills open standard. Skills created here also work with Gemini CLI, Cursor, Windsurf, and other agents supporting the standard.

When to Use

• Building a skill for AntiGravity or .agent/skills/ format
• Creating cross-platform skills (Claude Code + AntiGravity + others)
• Converting existing skills to the Agent Skills open standard

Folder Structure

Every skill must follow this hierarchy:

<skill-name>/
  SKILL.md          # Required: Main logic and instructions (<500 lines)
  scripts/          # Optional: Helper scripts (validation, API calls)
  examples/         # Optional: Reference implementations
  resources/        # Optional: Templates, checklists, assets

YAML Frontmatter Standards

---
name: gerund-form-name        # e.g., "testing-code", "managing-databases"
description: Third person.    # Include specific trigger keywords. Max 1024 chars.
allowed-tools: Read, Write    # Comma-separated tool restrictions
---

Rules:

• name: Gerund form, max 64 chars, lowercase + numbers + hyphens only
• description: Written in third person with specific triggers/keywords
• No "claude" or "anthropic" in the name

Writing Principles (The "Claude Way")

1. Conciseness — Assume the agent is smart. Don't explain basics. Focus on unique logic.
2. Progressive Disclosure — Keep SKILL.md under 500 lines. Link to secondary files only one level deep.
3. Forward Slashes — Always use / for paths, never \.
4. Degrees of Freedom:
   • Bullet Points — High-freedom tasks (heuristics, guidelines)
   • Code Blocks — Medium-freedom (templates, schemas)
   • Specific Bash Commands — Low-freedom (fragile operations that must be exact)

Workflow & Feedback Loops

For complex tasks, include:

1. Checklists — Markdown checklist the agent copies and updates to track state
2. Validation Loops — Plan-Validate-Execute pattern (check config BEFORE applying changes)
3. Error Handling — Scripts are "black boxes" — tell agent to run --help if unsure

Cross-Platform Skill Creation

To create a skill that works in BOTH Claude Code and AntiGravity:

Step 1: Build the AntiGravity version

.agent/skills/<name>/
  SKILL.md
  scripts/
  resources/

Step 2: Symlink or copy to Claude Code

.claude/skills/<name>/
  SKILL.md      # Same file, Claude Code frontmatter is a superset

Step 3: Add Orchestrator integration (optional)

skills/<name>/
  config.yaml   # Orchestrator-specific: compatible_agents, domain, priority
  SKILL.md      # Same content

Frontmatter Compatibility

Field	Claude Code	AntiGravity	Both
name	Yes	Yes	Yes
description	Yes	Yes	Yes
allowed-tools	Yes	Yes	Yes
context: fork	Yes	No	Claude only
model	Yes	No	Claude only
hooks	Yes	No	Claude only

Skill Template

When creating a new skill, use this template:

---
name: [gerund-name]
description: [3rd-person description with trigger keywords]
allowed-tools: [tools needed]
---

# [Skill Title]

## When to Use This Skill
- [Trigger scenario 1]
- [Trigger scenario 2]

## Workflow
1. [Step with clear instruction]
2. [Step with validation]
3. [Step with output]

## Instructions
[Specific logic, code snippets, or rules]

## Checklist
- [ ] [Verification item 1]
- [ ] [Verification item 2]

## Resources
- [Link to scripts/ or resources/ if applicable]

Output Convention

When generating a skill, output:

1. The full directory structure
2. Complete SKILL.md content
3. Any supporting files (scripts, resources, examples)
4. Installation instructions for the target platform

Notes

• Test both /skill-name invocation and natural language triggering
• Verify skills don't exceed the character budget (2% of context window)
• For skills with side effects (API calls, file generation), set disable-model-invocation: true