AG Kit is a toolkit that gives Google Antigravity coding agents a structured workspace with rules, skills, specialist agents, workflows, persistent memory, orchestration, MCP guidance, and a safety hook. It is for building and operating agent workflows in Antigravity, and its catalogue entries provide parts of that workspace contract.
Borrowing it
Nothing to install: this file belongs to vudovn/ag-kit. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/vudovn/ag-kit/main/.agents/skills/game-development/2d-games/SKILL.mdgit clone --depth 1 https://github.com/vudovn/ag-kitWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/vudovn/ag-kit/2d-games)<a href="https://agentmods.dev/skills/vudovn/ag-kit/2d-games"><img src="https://agentmods.dev/badge/skills/vudovn/ag-kit/2d-games/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/vudovn/ag-kit/2d-games"><img src="https://agentmods.dev/badge/skills/vudovn/ag-kit/2d-games.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00020 | $0.00554 |
| Opus 5.5 | $0.00008 | $0.00222 |
| Sonnet 5.5 | $0.00004 | $0.00111 |
| Haiku 4.5 | $0.00002 | $0.00055 |
Grade A, and why
2d-games scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
Copies of this mod
8 near-identical copies found in the catalogue:
- 2d-games — 100% identical, 0 lines differ
- 2d-games — 100% identical, 0 lines differ
- 2d-games — 100% identical, 0 lines differ
- 2d-games — 100% identical, 0 lines differ
- 2d-games — 100% identical, 0 lines differ
- 2d-games — 92% identical, 3 lines differ
- 2d-games — 92% identical, 1 lines differ
- 2d-games — 83% identical, 8 lines differ
How it starts
The opening of the file, as written. The whole thing — 120 lines — stays where its author put it; the contents beside it link to each section on GitHub.
2D Game Development
Principles for 2D game systems.
1. Sprite Systems
Sprite Organization
| Component | Purpose |
|---|---|
| Atlas | Combine textures, reduce draw calls |
| Animation | Frame sequences |
| Pivot | Rotation/scale origin |
| Layering | Z-order control |
Animation Principles
- Frame rate: 8-24 FPS typical
- Squash and stretch for impact
- Anticipation before action
- Follow-through after action
2. Tilemap Design
Tile Considerations
| Factor | Recommendation |
|---|---|
| Size | 16x16, 32x32, 64x64 |
| Auto-tiling | Use for terrain |
| Collision | Simplified shapes |
Layers
| Layer | Content |
|---|---|
| Background | Non-interactive scenery |
| Terrain | Walkable ground |
| Props | Interactive objects |
| Foreground | Parallax overlay |
3. 2D Physics
Collision Shapes
| Shape | Use Case |
|---|---|
| Box | Rectangular objects |
| Circle | Balls, rounded |
| Capsule | Characters |
| Polygon | Complex shapes |
Physics Considerations
- Pixel-perfect vs physics-based
- Fixed timestep for consistency
- Layers for filtering
4. Camera Systems
Camera Types
| Type | Use |
|---|---|
| Follow | Track player |
| Look-ahead | Anticipate movement |
| Multi-target | Two-player |
| Room-based | Metroidvania |
Screen Shake
- Short duration (50-200ms)
- Diminishing intensity
- Use sparingly
5. Genre Patterns
Platformer
- Coyote time (leniency after edge)
- Jump buffering
- Variable jump height
Top-down
- 8-directional or free movement
- Aim-based or auto-aim
- Consider rotation or not
6. Anti-Patterns
| ❌ Don't | ✅ Do |
|---|---|
| Separate textures | Use atlases |
| Complex collision shapes | Simplified collision |
| Jittery camera | Smooth following |
| Pixel-perfect on physics | Choose one approach |
Remember: 2D is about clarity. Every pixel should communicate.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 1mo ago First seen · 120 lines · 20 tokens per session scan A f31d95e041d0
2d-games is a skill published in the GitHub repository vudovn/ag-kit (8,199 stars, last pushed 3d ago), licensed MIT. It adds 20 tokens to every session and 554 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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unity-manual-component
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threejs-exposure-color-grading
Build a measured exposure and grading path in Three.js. Use for a 64x36 encoded luminance meter, asynchronous readback, weighted log-average exposure, asymmetric adaptation, single tone-map ownership, and a generated 32-cube post-tone-map LUT.