jame581/GodotPrompter

# Bad Cross-Ref Fixture

> **Related skills:** **physics-system** for physics, **definitely-does-not-exist** for nonsense.

## 1. Section

See **also-not-real** skill for more.

## Checklist
- [ ] item

# Bad Frontmatter Fixture

This file is missing YAML frontmatter and should be flagged as an error.

## 1. Section
- [ ] checklist

# Missing Checklist Fixture

> **Related skills:** **physics-system** for physics.

## 1. Section

Some content with no checklist at the end.

# Session Card Broken Fixture

> **Related skills:** **godot-brainstorming** for design exploration.

## Coexistence

<!-- SESSION-CARD-START -->
<!-- SESSION-CARD-END -->

## Implementation Checklist

- [ ] This fixture exists to be rejected

# Session Card Missing Fixture

> **Related skills:** **godot-brainstorming** for design exploration.

## Coexistence

<!-- SESSION-CARD-START -->
This region never closes.

## Implementation Checklist

- [ ] This fixture exists to be rejected

# Session Card Oversized Fixture

> **Related skills:** **godot-brainstorming** for design exploration.

## Coexistence

<!-- SESSION-CARD-START -->
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# token-budget-near

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# token-budget-over

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# 2D Essentials in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **player-controller** for CharacterBody2D movement patterns, **animation-system** for AnimatedSprite2D and sprite animation, **physics-system** for collision shapes and raycasting, **camera-system** for Camera2D follow and shake, **shader-basics** for 2D shaders and post-processing, **godot-optimization** for rendering and draw call tuning.

---

## 1. Canvas Layers and Draw Order

### Draw Order Rules

Within a single canvas layer, nodes draw in **scene tree order** — nodes listed lower in the Scene panel draw **on top**. Use `z_index` to override without rearranging the tree.

# 3D Essentials in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **rendering-pipeline** for renderer choice, lighting strategy, AA and resolution scaling, **player-controller** for CharacterBody3D movement, **physics-system** for 3D collision shapes and raycasting, **camera-system** for Camera3D follow and transitions, **shader-basics** for spatial shaders and post-processing, **godot-optimization** for 3D performance tuning, **animation-system** for AnimationTree and 3D animation blending.

---

## 1. 3D Coordinate System & Core Nodes

### Coordinate System

Godot uses a **right-handed** coordinate system with metric units (1 unit = 1 meter):

# Ability System

Build a data-driven ability system from Godot-native parts: abilities are `Resource`s, an `AbilityComponent` node owns and runs them, and effects/stats/tags compose on top. No third-party addon required.

> **Related skills:** **resource-pattern** for the `Resource` data containers, **component-system** for the component node pattern, **event-bus** for cross-system ability events, **state-machine** for caster states (e.g. casting/stunned), **hud-system** for cooldown UI.

---

## 1. Architecture overview

An ability system in Godot 4.x is built from three collaborating layers:

- **Data layer — `Ability` (Resource):** Each ability is a `Resource` subclass with exported fields (`ability_name`, `cost`, `cooldown`, `cast_time`) and two methods: `can_activate(caster) -> bool` to validate preconditions, and `activate(caster) -> void` to execute the effect. Storing abilities as Resources lets designers create and balance them in the Godot editor without touching code.

# Addon Development in Godot 4.3+

Editor plugins extend the Godot editor itself: custom node types, inspector panels, dock widgets, 3D gizmos, and toolbar buttons. All examples target Godot 4.3+ with no deprecated APIs.

> **Related skills:** **resource-pattern** for custom Resource editors, **godot-ui** for editor panel UI, **csharp-godot** for C# plugin development.

---

## 1. Plugin Structure

Every plugin lives inside `addons/` at the project root. Godot discovers plugins by scanning for `plugin.cfg` files.

```
res://

# AI Navigation in Godot 4.3+

Cover NavigationAgent2D/3D, steering behaviors, behavior trees, and patrol patterns. All examples target Godot 4.3+ with no deprecated APIs.

> **Related skills:** **state-machine** for AI state management, **component-system** for modular AI behaviors, **player-controller** for movement physics patterns, **math-essentials** for pathfinding vectors and steering math, **limboai** for BT + HSM with a visual editor, **beehave** for lightweight GDScript behavior trees. For a structured behavior tree (rather than steering/navigation), see the comparison tables in **limboai** and **beehave**.

---

## 1. Navigation Setup

### Scene Structure

```
World (Node2D or Node3D)

# Animation System in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **state-machine** for gameplay state management, **player-controller** for movement that drives animation, **component-system** for reusable animation components, **2d-essentials** for TileMaps, parallax scrolling, 2D lights, and canvas layer organization, **3d-essentials** for AnimationTree and 3D animation blending, **shader-basics** for shader-driven hit flash and dissolve effects, **tween-animation** for code-driven motion alongside keyframe animation.

---

## 1. Core Concepts

### AnimationPlayer vs AnimationTree

| Node              | Use For                                  | Complexity | Notes                                              |
|-------------------|------------------------------------------|------------|----------------------------------------------------|

# Assets Pipeline in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **audio-system** for audio playback and bus architecture, **3d-essentials** for 3D materials and lighting, **2d-essentials** for 2D rendering and sprites, **animation-system** for imported animations, **godot-optimization** for asset-related performance, **multithreading** for threaded resource loading.

---

## 1. How Importing Works

### The Import System

When you add a file to `res://`, Godot auto-imports it based on its type. Import settings are stored in `.import` sidecar files alongside the original.

# Audio System in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **event-bus** for decoupled audio triggers, **save-load** for persisting audio settings, **resource-pattern** for audio data containers.

---

## 1. Core Concepts

### Audio Node Types

| Node                   | Dimensions | Use For                                       |
|------------------------|------------|-----------------------------------------------|

# Beehave

> **Related skills:** **ai-navigation** for the movement leaves drive, **state-machine** for core-engine FSM, **limboai** for a heavier C++ BT+HSM alternative, **godot-brainstorming** for choosing an AI approach.

> **Addon:** Beehave · version `v2.9.2` · Godot 4.1+ · MIT · source: https://github.com/bitbrain/beehave · written in GDScript (no official C# API — this skill is GDScript-only by design).

---

## 1. When to use Beehave

| Approach | Best for |
|---|---|
| Core-engine FSM (`state-machine` skill) | Simple agents, < 5 states, no addon |
| **Beehave** (GDScript addon) | Lightweight BT, GDScript-only projects, fast iteration |

# Camera Systems in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **player-controller** for first-person camera setup, **state-machine** for camera state transitions, **godot-optimization** for camera culling and performance, **physics-system** for physics interpolation and camera smoothing, **2d-essentials** for canvas layers, parallax scrolling, and coordinate conversion, **math-essentials** for smoothstep and lerp-based interpolation, **tween-animation** for camera shake and cinematic transitions, **phantom-camera** for a Cinemachine-style camera addon.

---

## 1. Camera2D Basics

### Key Properties

| Property | Type | Description |
|---|---|---|

# Component System in Godot 4.3+

Build behavior through composition. Attach small, focused components to any entity rather than climbing an inheritance chain. All examples target Godot 4.3+ with no deprecated APIs.

> **Related skills:** **scene-organization** for scene tree composition, **event-bus** for decoupled component communication, **resource-pattern** for data-driven component configuration, **physics-system** for Area2D/3D overlap detection and collision shapes, **ability-system** for an AbilityComponent example built on this pattern.

---

## 1. Why Components

| Problem with inheritance | How components solve it |
|--------------------------|-------------------------|
| Deep chains are brittle — change one class, break many | Each component is an isolated scene with a single job |
| Sharing behavior across unrelated entities requires awkward base classes | Drop a component onto any entity that needs that behavior |

# C# in Godot 4.3+

This skill covers C#-specific conventions, API differences from GDScript, project setup, and interop patterns. All examples are C# only. Target Godot 4.3+ with the GodotSharp NuGet package.

> **Related skills:** **csharp-signals** for C# signal patterns, **godot-project-setup** for C# project scaffolding, **godot-testing** for C# testing with gdUnit4, **gdextension** for native C++ when C# is not enough, **multithreading** for C# concurrency.

---

## 1. C# vs GDScript Syntax Comparison

| GDScript | C# Equivalent | Notes |
|---|---|---|
| `var x = 5` | `var x = 5;` or typed `int x = 5;` | C# `var` infers type at compile time |
| `func MyMethod() -> void:` | `public void MyMethod() { }` | Methods are PascalCase in C# |

# Signals in C# (Godot 4.x)

This skill is **C# only**. For general C# conventions and project setup, see the **csharp-godot** skill. Godot signals in C# require a different mental model from GDScript: delegates declared with `[Signal]`, strongly-typed `+=`/`-=` connections, and mandatory disconnection in `_ExitTree()`. All examples target Godot 4.x with no deprecated APIs.

> **Related skills:** **csharp-godot** for C# conventions and project setup, **event-bus** for global signal hub architecture, **component-system** for signal-based component communication.

---

## 1. Signal Declaration

Signals are declared as `public delegate void` with the `[Signal]` attribute inside a `partial class` that extends a Godot type. The delegate name **must** end with `EventHandler` — Godot strips that suffix to produce the signal name exposed to the engine.

```csharp
using Godot;

# Dedicated Server in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, C# follows.

**Related skills:** See **multiplayer-basics** for ENet setup, RPCs, and authority model. See **multiplayer-sync** for state synchronization and interpolation.

---

## 1. Headless Export

A dedicated server runs without a display, GPU, or audio device. Godot supports this through the `--headless` flag and a dedicated export preset.

### --headless Flag

# Dependency Injection in Godot 4.3+

Patterns for wiring dependencies between systems so nodes stay loosely coupled, swappable, and testable. All examples target Godot 4.3+ with no deprecated APIs.

> **Related skills:** **godot-testing** for test-friendly architecture, **event-bus** for signal-based decoupling, **godot-project-setup** for autoload registration.

---

## 1. The Problem

Tight coupling makes code hard to test, extend, and swap. The most common form in Godot is reaching directly into a global autoload from everywhere in the codebase.

```gdscript
# BAD — tight coupling via direct autoload access scattered everywhere

# Dialogue Manager

> **Related skills:** **dialogue-system** for hand-rolled dialogue data structures, **localization** for translating lines, **popochiu** for full adventure-game workflows.

> **Addon:** Dialogue Manager · version `v3.10.4` · Godot 4.6 · MIT · source: https://github.com/nathanhoad/godot_dialogue_manager · GDScript with official C# support.

---

## 1. When to use Dialogue Manager

| Approach | Best for |
|---|---|
| **dialogue-system** skill (hand-rolled `Resource` data) | Full control over data shape, no addon dependency, small dialogue trees |
| **Dialogue Manager** | Script-like `.dialogue` text format, branching responses, conditions/mutations, translation pipeline, visual editor tab, official C# wrapper |

# Dialogue Systems in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **resource-pattern** for dialogue data as Resources, **godot-ui** for Control node layout, **state-machine** for dialogue flow management, **save-load** for dialogue state persistence, **dialogue-manager** for a full-featured dialogue addon, **popochiu** for adventure games.

---

## 1. Architecture Overview

```
┌─────────────────────────────────────────────────────────┐
│                        UI Layer                         │
│   DialogueUI (Control)                                  │

# Event Bus in Godot 4.3+

A global signal hub that lets unrelated nodes communicate without holding references to each other. All examples target Godot 4.3+ with no deprecated APIs.

> **Related skills:** **component-system** for direct signal communication between components, **csharp-signals** for C#-specific signal patterns, **dependency-injection** for alternative decoupling approaches, **ability-system** for an EventBus usage example with ability events.

---

## 1. What is an Event Bus

An EventBus is a singleton autoload that acts as a central registry for signals. Instead of nodes connecting directly to each other, every node connects to (or emits on) the shared EventBus. This removes the need for one node to hold a reference to another.

```
Without EventBus             With EventBus

# Export Pipeline in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, C# follows where applicable.

> **Related skills:** **godot-testing** for CI/CD test integration, **godot-optimization** for pre-export performance checks, **responsive-ui** for platform-specific resolution settings, **mobile-development** for Android/iOS export specifics, **web-export** for browser builds and hosting.

---

## 1. Export Presets

### Creating Presets in the Editor

Open **Project → Export**, click **Add…**, and select the target platform. Each preset maps to one entry in `export_presets.cfg`. You can create multiple presets for the same platform (e.g., a debug build and a release build for Windows).

# GDExtension

Run native C++ (or Rust) in Godot as a shared library **without recompiling the engine**. Use it for performance-critical code, wrapping existing C/C++ libraries, or language bindings.

> **Related skills:** **csharp-godot** for when C# is enough, **gdscript-advanced** for GDScript performance idioms first, **godot-optimization** for profiling before going native, **addon-development** for distributing the result, **export-pipeline** for shipping the binaries.

---

## 1. When to reach for GDExtension

Reach for GDScript or C# for almost all game logic. Choose GDExtension only when you genuinely need it:

- **Native speed** in a hot loop that GDScript/C# can't keep up with (profile first — see **godot-optimization**).
- **Wrapping a C/C++ library** you must call directly.

# GDScript Advanced

Production-grade GDScript depth — for shipping games, not for learning the language. Pair with **gdscript-patterns** for fundamentals.

> **Related skills:** **gdscript-patterns** for language fundamentals, **godot-optimization** for engine-side perf work, **godot-debugging** for runtime diagnosis, **csharp-godot** for the C# alternative.

> **Intent:** This skill is GDScript-only by design (allowlisted). C# users should read `csharp-godot`. Adding C# parity here would undermine the audience split.

## 1. When to reach for advanced GDScript

You're past `gdscript-patterns` when:

- You're hitting a profiler bottleneck and need to know which idioms are fast
- You're writing editor tools and need `@tool` lifecycle correctness

# GDScript Patterns in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs.

> **Related skills:** **gdscript-advanced** for production-grade depth (performance idioms, metaprogramming, @tool lifecycle, profiler-driven idioms), **godot-code-review** for style rules and anti-patterns, **csharp-godot** for GDScript-to-C# translation, **state-machine** for state patterns, **event-bus** for signal architecture.

> **Note:** This skill is GDScript-specific by design. For C# patterns, see **csharp-godot** and **csharp-signals**.

---

## 1. Static Typing

### Type Hints

# Godot Brainstorming

A structured design process for Godot 4.3+ features and systems — from blank slate to a clear scene tree, signal map, and data flow before you write a single line of implementation code.

> **Related skills:** **godot-grill** for settling open design decisions first, **scene-organization** for scene tree composition patterns, **component-system** for component-based architecture, **event-bus** for signal-based communication design.

---

## Process: How to Brainstorm

Do NOT jump straight to designing. Follow these steps:

### Step 1: Settle the decisions
If the request has open design decisions (scope, dimension, authority, data home, …), invoke `godot-prompter:godot-grill` and let it run to its end. Skip it when a record in the project's decisions or ADR directory already covers this feature, or the user has stated the decisions. Either way, check what already exists (code, scenes, assets). Carry the record into Step 2 — approaches must respect its settled rows.

# Godot Code Review

A structured review guide for Godot 4.3+ projects covering GDScript and C#. Work through each checklist section, then produce a review summary using the output template at the end.

> **Related skills:** **godot-testing** for TDD and test coverage, **scene-organization** for scene tree best practices, **godot-optimization** for performance review.

---

## 1. Node & Scene Architecture

- [ ] Each scene has a single, clear responsibility (player, enemy, UI widget, etc.)
- [ ] Inheritance chains are shallow — prefer composition via child nodes over deep `extends` hierarchies
- [ ] Autoloads (singletons) are used sparingly; only truly global state belongs there
- [ ] Node references traverse only to direct children — no `get_parent()` chains

# Godot Debugging

This skill covers systematic debugging for Godot 4.3+ projects in both GDScript and C#. It covers print techniques, breakpoints, signal tracing, the built-in profiler, scene tree inspection, common error patterns, and a step-by-step debugging checklist.

> **Related skills:** **godot-optimization** for performance profiling, **godot-testing** for regression tests after fixes, **csharp-signals** for C# signal debugging patterns.

---

## 1. Print Debugging

### GDScript

Godot provides several print functions with different purposes. Choose based on the severity and context of what you are logging.

# Godot Grill

Settle the decisions only the developer can make, before anyone designs a scene tree or writes
code. The output is a **decision record**, not a design.

> **Related skills:** **godot-brainstorming** for the scene tree, signal map, and plan once decisions are settled, **scene-organization** for composition vs. inheritance trade-offs, **godot-mentor** for teaching-mode delivery of what follows.

## 1. Decisions, not facts

Ask only what **only the user knows**: intent, constraints, priorities, taste.

Node types, API signatures, and version differences are **facts**. Look them up
(`godot-brainstorming/references/node-selection.md`, the domain skills), decide, and record the
choice. Never spend a question on one.

# Godot Mentor Mode

> **Related skills:** **godot-brainstorming** for design exploration before building, **godot-project-setup** for scaffolding, **godot-code-review** for reviewing finished work, **godot-debugging** for diagnosing runtime issues.

Mentor mode changes the **shape** of an answer, not its **source of truth**. It wraps the
domain skills — it never replaces them.

## 1. The wrapping rule

**Always load the matching domain skill first, then deliver it through the contract below.**

```
"add double jump"  +  mentor mode
   1. invoke godot-prompter:player-controller   <- still authoritative

# Godot Optimization

This skill covers performance optimization for Godot 4.3+ projects in both GDScript and C#. It covers the built-in profiler, draw call reduction, physics tuning, GDScript performance patterns, memory management, object pooling, and a reference table of common bottlenecks.

> **Related skills:** **godot-debugging** for systematic debugging and profiling, **godot-code-review** for performance review checklist, **export-pipeline** for release build optimization, **physics-system** for collision shapes, layers, and physics body types, **2d-essentials** for 2D mesh optimization, particle performance, and draw order tuning, **multithreading** for moving work off the main thread, **mobile-development** for mobile performance budgets.

---

## 1. Using the Profiler

### Frame Time Budget

At 60 fps, the entire frame (update, physics, rendering) must complete in **16.6 ms**. At 30 fps the budget is 33.3 ms. Any single system that consumes the majority of that budget is a bottleneck.

# Godot Project Setup

This skill scaffolds a new Godot 4.3+ project with recommended directory structure, project settings, autoloads, and version control configuration.

> **Related skills:** **scene-organization** for structuring scene trees, **event-bus** for the EventBus autoload pattern, **save-load** for the SaveManager autoload pattern.

## Recommended Directory Structure (Split Layout)

The split layout separates assets, scenes, and scripts into distinct top-level directories. This scales well for medium-to-large projects and makes it easy to find resources by type.

```
res://
├── assets/
│   ├── audio/

# Godot Testing

This skill covers test-driven development (TDD) for Godot 4.3+ projects using GUT (Godot Unit Testing) and gdUnit4. It includes framework selection, full RED-GREEN-REFACTOR examples, test structure, running tests in CI, and common testing patterns.

> **Related skills:** **godot-code-review** for review checklists, **dependency-injection** for test-friendly architecture, **export-pipeline** for CI/CD test automation.

## Framework Selection

| Feature               | GUT                              | gdUnit4                           |
|-----------------------|----------------------------------|-----------------------------------|
| Language              | GDScript-first, limited C#       | GDScript + C# (first-class)       |
| Install               | AssetLib or git submodule        | AssetLib or git submodule         |
| Editor integration    | Built-in GUT panel               | Built-in inspector + panel        |
| Mocking               | `double()` / `stub()` API        | `mock()` / `spy()` API            |

# Godot UI — Control Nodes, Themes & Layout

All examples target Godot 4.3+ with no deprecated APIs; GDScript first, then C#.

> **Related skills:** **responsive-ui** for multi-resolution scaling, **hud-system** for in-game HUD patterns, **dialogue-system** for dialogue UI presentation, **tween-animation** for UI transition and animation effects.

---

## 1. Control Node Hierarchy

### How Control Differs from Node2D

`Control` is the base class for all UI nodes — it lives in a separate scene-tree branch from `Node2D`/`Node3D` with a fundamentally different layout model.

# HUD Systems in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **godot-ui** for Control node layout and themes, **component-system** for HealthComponent integration, **event-bus** for score/notification signals, **inventory-system** for inventory UI patterns, **2d-essentials** for CanvasLayer setup and draw order, **ability-system** for cooldown bar and resource bar binding patterns.

---

## 1. HUD Architecture

### Why CanvasLayer

A `CanvasLayer` renders its children with its own transform, independent of the `Camera2D` (unless `follow_viewport_enabled` is on); a `Camera3D` never moves 2D nodes. Without it, HUD nodes on the scene root's default canvas (layer 0) move with a `Camera2D` when you pan or zoom, because the camera sets that canvas's transform. Wrapping all HUD nodes in a `CanvasLayer` keeps the HUD in place; layer `≥ 1` (the default is 1) draws it above the world.

# Input Handling in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **player-controller** for movement driven by input, **godot-ui** for UI input focus and navigation, **save-load** for persisting custom key bindings, **responsive-ui** for touch vs desktop input adaptation, **xr-development** for XR controller and hand tracking input, **mobile-development** for mobile sensors and app lifecycle.

---

## 1. Core Concepts

### Input Flow

```
Hardware Event (key, mouse, gamepad)

# Inventory Systems in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. This skill carries the decisions; the implementations live in `references/` (GDScript first, then C#) — load the one you need.

> **Related skills:** **resource-pattern** for custom Resource data containers, **save-load** for inventory serialization, **event-bus** for inventory change notifications, **hud-system** for inventory UI display, **popochiu** for adventure-game inventory.

---

## 1. Architecture Overview

```
┌─────────────────────────────────────────────────────────┐
│                        UI Layer                         │
│   InventoryUI (Control)                                 │

# LimboAI

> **Related skills:** **ai-navigation** for movement the tasks drive, **state-machine** for core-engine FSM (when you don't need an addon), **godot-brainstorming** for choosing an AI approach.

> **Addon:** LimboAI · version `v1.8.0` · Godot 4.6+ (GDExtension) · MIT · source: https://github.com/limbonaut/limboai · written in C++ (GDExtension; engine-module build also available). GDExtension exposes GDScript; **C# requires the module build** (not GDExtension in v1.8.0), and the v1.8.0 module build targets **Godot 4.7**.

---

## 1. When to use LimboAI

| Approach | Best for |
|---|---|
| Core-engine FSM (`state-machine` skill) | Simple agents, < 5 states, no addon |
| **Beehave** (GDScript addon) | Lightweight BT, GDScript-only projects |

# Localization in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs; GDScript first, then C#.

> **Related skills:** **godot-ui** for Control nodes and theme management, **save-load** for persisting language settings, **responsive-ui** for layout adjustments per locale.

---

## 1. Core Concepts

### How Godot Localization Works

1. **Wrap all user-facing strings** in `tr()` — Godot's translation function
2. **Create translation files** (CSV or PO) mapping keys to translated strings

# Game Math in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **player-controller** for movement physics, **ai-navigation** for pathfinding math, **camera-system** for camera interpolation, **tween-animation** for easing curves, **physics-system** for collision math.

---

## 1. Vector Operations

### Essential Vector Methods

| Method                  | Returns   | Description                                   |
|-------------------------|-----------|-----------------------------------------------|

# Mobile Development

Ship a Godot 4.x game to Android and iOS. This covers the platform-specific deltas beyond a generic export: signing, lifecycle, permissions, plugins, IAP, device features, and the mobile renderer/perf budget.

> **Related skills:** **export-pipeline** for the generic export flow and CI/CD, **responsive-ui** for safe-area layout, **input-handling** for touch, **godot-optimization** for mobile performance, **csharp-godot** for C# mobile caveats.

---

## 1. Export & signing

**Android:** OpenJDK 17 and the Android SDK; set `Java SDK Path` + `Android SDK Path` in **Editor Settings** (per-user, not per-project). Generate a release keystore:

```bash
keytool -v -genkey -keystore mygame.keystore -alias mygame -keyalg RSA -validity 10000

# Multiplayer Basics in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, C# follows.

**Related skills:** See **multiplayer-sync** for state synchronization and interpolation. See **dedicated-server** for headless export and server deployment.

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## 1. Multiplayer Architecture

Godot uses a **client-server model** built on top of `MultiplayerAPI`. One peer acts as the server; all others are clients. Every peer has a unique integer ID assigned by the network layer:

| Peer ID | Role |
|---------|------|

# Multiplayer Synchronization in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **multiplayer-basics** for ENet setup, RPCs, and authority model, **dedicated-server** for headless export and deployment, **physics-system** for physics interpolation and RigidBody synchronization.

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## 1. MultiplayerSynchronizer

`MultiplayerSynchronizer` is Godot's built-in node for replicating properties across the network. Add it as a child of the node whose state you want to share.

### What It Does

# Multithreading

Run expensive work off the main thread without corrupting the scene tree. Prefer `WorkerThreadPool` for short parallel jobs; reach for `Thread`/`Mutex`/`Semaphore` only when you need a long-lived worker.

> **Related skills:** **godot-optimization** for profiling before threading, **assets-pipeline** for asset import, **csharp-godot** for C# specifics, **gdscript-advanced** for async/await pitfalls.

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## 1. Threading model & safety rules

The main thread owns the scene tree — **interacting with the active scene tree is not thread-safe.** Observe these doc-sourced rules:

- **Servers** (RenderingServer, PhysicsServer) are thread-safe **only after enabling it in Project Settings** (`Rendering > Driver > Threads > Thread Model = Separate` — `Multi-Threaded` on 4.3, and experimental; `Physics > {2D,3D} > Run on Separate Thread`). Servers handle thousands of thread-driven instances well.
- **NavigationServer2D/3D are thread-safe and thread-friendly** (true parallel queries); tune `Navigation > Pathfinding > Max Threads` (4.4+).

# Particle Systems in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **shader-basics** for custom particle shaders, **3d-essentials** for lighting and environment that affect particles, **2d-essentials** for 2D rendering context, **tween-animation** for code-driven VFX timing, **godot-optimization** for particle performance tuning.

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## 1. Core Concepts

### GPU vs CPU Particles

| Node                | Processing | Features                                | Use For                        |
|---------------------|------------|-----------------------------------------|--------------------------------|

# Phantom Camera

> **Related skills:** **camera-system** for hand-rolled camera patterns, **tween-animation** for the easing concepts the transitions build on.

> **Addon:** Phantom Camera · version `v0.11.0.2` · Godot 4.4+ · MIT · source: https://github.com/ramokz/phantom-camera · nodes are GDScript, plus an official C# wrapper API (`namespace PhantomCamera`) shipped as source `.cs` files in the addon. **Pre-1.0:** minor versions may break API.

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## 1. When to use Phantom Camera vs. `camera-system`

| Approach | Best for |
|---|---|
| Hand-rolled (`camera-system` skill) | One camera, simple follow/shake, no addon dependency |
| **Phantom Camera** | Multiple camera "shots" that need priority-based switching, dead-zone/group/path/third-person follow logic, and smooth resource-driven tweens between them — Cinemachine-style workflow |

# Physics System in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **player-controller** for CharacterBody2D/3D movement patterns, **component-system** for hitbox/hurtbox composition, **godot-optimization** for physics performance tuning, **camera-system** for camera follow and interpolation, **multiplayer-sync** for networked physics, **2d-essentials** for tile collision setup and 2D canvas layers.

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## 1. Physics Body Types

Four collision-object types (the last three extend `PhysicsBody2D`/`3D`):

| Type | Moved by | Use for |
|------|----------|---------|

# Player Controllers in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **physics-system** for RigidBody, Area, raycasting, and collision shapes, **2d-essentials** for TileMaps, parallax, and 2D lighting, **3d-essentials** for CharacterBody3D and 3D movement setup, **state-machine** for movement state management, **camera-system** for camera follow and shake, **component-system** for hitbox/hurtbox integration, **animation-system** for animation driven by movement state, **input-handling** for InputMap actions and controller support, **ai-navigation** for enemy movement and pathfinding.

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## 1. Core Concepts

### CharacterBody vs RigidBody

| Body Type         | Use For                        | Physics Control | Notes                                                   |
|-------------------|--------------------------------|-----------------|----------------------------------------------------------|

# Popochiu

> **Related skills:** **dialogue-system** for hand-rolled dialogue data, **inventory-system** for generic inventory patterns, **save-load** for core-engine persistence.

> **Addon:** Popochiu · version `v2.1.1` · Godot 4.6 · MIT · source: https://github.com/carenalgas/popochiu · pure GDScript (no C# API — GDScript-only skill).

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## 1. When to use Popochiu

| Approach | Best for |
|---|---|
| Hand-rolled (`dialogue-system` + `inventory-system` + `state-machine`) | Custom genre, tight control over every system, no editor tooling needed |
| **Popochiu** | Full point-and-click adventure (AGS/PowerQuest-style): rooms, walk-to-click, verb-based interaction, dialog trees, inventory, save/load — wired together with dock-generated scaffolding |

# Procedural Generation in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **2d-essentials** for TileMapLayer usage, **3d-essentials** for 3D terrain meshes, **math-essentials** for vectors and transforms, **godot-optimization** for chunk loading and performance.

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## 1. Seeded Randomness

Always use seeds for reproducible generation. This enables shareable seeds, replay, and deterministic testing.

### GDScript

# Rendering Pipeline in Godot 4.3+

Project-level rendering decisions: which renderer runs where, how the lighting is built for it, how edges are smoothed, what resolution 3D renders at, and how to measure the result. All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

This skill picks the strategy; **3d-essentials** holds the per-node recipes (materials, light properties, GI setup, fog, decals).

> **Related skills:** **3d-essentials** for materials, lights, environment and GI node setup, **2d-essentials** for 2D lights and shadows, **shader-basics** for post-processing, compositor effects and the Shader Baker, **godot-optimization** for profiling CPU/GPU bottlenecks, **web-export** for the Compatibility-only browser target.

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## 1. Pick the Renderer First

The renderer decides which lighting features exist at all, so choose it before building the look.

# Resource Pattern in Godot 4.3+

Resources are Godot's built-in data containers. Use them for configuration, item definitions, character stats, and any data that lives outside the scene tree. All examples target Godot 4.3+ with no deprecated APIs.

> **Related skills:** **inventory-system** for Resource-based item definitions, **save-load** for Resource serialization, **component-system** for data-driven component configuration, **ability-system** for Resource-based ability definitions built on this pattern.

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## 1. What Are Resources

A `Resource` is a reference-counted data object that:

- Is saved as a `.tres` (text) or `.res` (binary) file on disk
- Is editable directly in the Godot Inspector

# Responsive UI in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **godot-ui** for Control node layout and themes, **export-pipeline** for platform-specific export settings, **godot-project-setup** for initial project resolution settings, **input-handling** for touch vs desktop input adaptation, **localization** for layout adjustments per locale, **mobile-development** for safe-area and notch handling.

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## 1. Project Settings for Resolution

Configure base resolution and stretch behaviour in `Project > Project Settings > Display > Window`.

Key settings and their keys in the `[display]` section of `project.godot`:

# Save / Load Systems in Godot 4.3+

Choose the right serialization strategy for your data type. All examples target Godot 4.3+ with no deprecated APIs.

> **Related skills:** **resource-pattern** for custom Resource data containers, **inventory-system** for inventory serialization patterns, **godot-project-setup** for SaveManager autoload setup, **popochiu** for adventure-framework saves.

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## 1. Strategy Comparison

| Strategy          | Best For                        | Readable | Editor Support | Notes                              |
|-------------------|---------------------------------|----------|----------------|------------------------------------|
| ConfigFile        | Settings, simple key-value data | Yes      | No             | Built-in INI-style, no extra deps  |
| JSON              | Game saves, flexible structures | Yes      | No             | Cross-platform, version-migratable |

# Scene Organization

A guide for structuring Godot 4.3+ scene trees: when to split, when to compose, and how nodes should communicate.

> **Related skills:** **component-system** for composition patterns, **event-bus** for decoupled communication, **godot-brainstorming** for scene tree planning, **2d-essentials** for TileMapLayer and CanvasLayer organization.

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## 1. Core Principle

Scenes are building blocks. Each scene encapsulates exactly one concept — a player, an enemy, a health bar, a weapon. A scene should be understandable in isolation, reusable without modification, and replaceable without breaking its neighbors.

> One scene = one responsibility. If you struggle to name a scene in two words or fewer, it is probably doing too much.

# Shaders in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs.

> **Related skills:** **animation-system** for shader-driven effects like hit flash, **godot-optimization** for shader performance considerations, **camera-system** for post-processing camera effects, **2d-essentials** for 2D lighting, pixel-art shaders, and CanvasTexture normal maps, **3d-essentials** for spatial shaders and environment materials, **particles-vfx** for custom particle shaders, **tween-animation** for animating shader parameters at runtime.

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## 1. Core Concepts

### Shader Types

| Shader Type | Applied To | Use For |
|------------------|--------------------------|--------------------------------------------------|

# State Machines in Godot 4.3+

Choose the right FSM pattern for your complexity level. All examples target Godot 4.3+ with no deprecated APIs.

> **Related skills:** **player-controller** for movement state integration, **ai-navigation** for AI state patterns, **resource-pattern** for resource-based state configuration, **animation-system** for AnimationTree states driven by FSM, **dialogue-system** for dialogue flow as a state machine, **ability-system** for caster state gating (casting/stunned), **limboai** for the LimboAI addon's HSM (`BTState`) if you need a behavior tree alongside your FSM, **beehave** for a GDScript-only BT alternative.

> **When to reach for an addon:** This skill covers the built-in FSM patterns (enum, node-based, resource-based). If your agent needs a full behavior tree, see **limboai** (C++ + HSM, Godot 4.6+) or **beehave** (pure GDScript, Godot 4.1+) instead.

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## 1. Approach Comparison

| Approach       | Complexity | Best For                              |
|----------------|------------|---------------------------------------|

# Tweens in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **animation-system** for AnimationPlayer/AnimationTree (keyframe-based), **godot-ui** for UI transitions, **shader-basics** for tweening shader parameters, **camera-system** for camera shake and transitions, **math-essentials** for easing curves and interpolation math, **particles-vfx** for code-driven VFX timing and sequencing.

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## 1. Core Concepts

### Tween vs AnimationPlayer

| Feature         | Tween (code-driven)                        | AnimationPlayer (data-driven)              |
|-----------------|--------------------------------------------|--------------------------------------------|

# Using GodotPrompter

> **Related skills:** **godot-project-setup** for scaffolding a new project, **godot-grill** for settling open design decisions first, **godot-brainstorming** for design exploration, **godot-code-review** for reviewing finished code, **godot-debugging** for diagnosing runtime issues.

GodotPrompter provides Godot 4.x domain-specific skills for AI coding agents. Skills cover project setup, architecture patterns, gameplay systems, UI, multiplayer, testing, and deployment — for both GDScript and C#.

## How to Access Skills

**In Claude Code:** Use the `Skill` tool with the skill name (e.g., `Skill: "godot-prompter:state-machine"`).

**In Copilot CLI:** Use the `skill` tool. Skills are auto-discovered from installed plugins.

**In Gemini CLI:** Deprecated (succeeded by Antigravity CLI).

# Web Export in Godot 4.3+

Ship a Godot 4.x game as HTML5/WebAssembly. This covers what is different from a desktop export: the renderer, threading and server headers, browser interop, persistence, and the input and audio rules browsers enforce. All examples target Godot 4.3+ with no deprecated APIs.

**C# projects cannot export to Web in Godot 4** — the .NET editor refuses the export (still true in 4.7.2). The code in this skill is GDScript only for that reason; a C# game that needs a browser build must be ported to GDScript or stay on Godot 3.

> **Related skills:** **export-pipeline** for presets, CLI export and CI/CD, **web-services** for HTTP and WebSockets from the browser, **rendering-pipeline** for what the Compatibility renderer can and cannot do, **audio-system** for buses and playback, **save-load** for save formats.

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## 1. What Changes on Web

| Area | On Web |
|---|---|

# Web Services in Godot 4.3+

Talk to REST APIs, leaderboards, analytics, login services, and other HTTP/WebSocket backends. All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **multiplayer-basics** for real-time game networking with WebSocketMultiplayerPeer, **save-load** for persisting tokens and cached responses, **web-export** for CORS and browser limits, **mobile-development** for Android export permissions, **multithreading** for heavy response parsing off the main thread.

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## 1. Picking the Tool

| Need | Use | Why |
|---|---|---|
| Ordinary REST call, file or image download | `HTTPRequest` node | Handles connect, redirects, gzip, timeout; emits one signal when done |
| Streaming a response, custom keep-alive, many requests to one host | `HTTPClient` | Low-level; you call `poll()` and drive the state machine yourself |

# XR Development in Godot 4.3+

All examples target Godot 4.3+ with no deprecated APIs. GDScript is shown first, then C#.

> **Related skills:** **3d-essentials** for 3D rendering and environment, **physics-system** for 3D physics interactions, **input-handling** for non-XR input patterns, **export-pipeline** for platform exports.

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## 1. XR Setup

### Enabling OpenXR

1. OpenXR is built into the engine — there is no plugin to enable.
2. **Project Settings → XR → OpenXR → Enabled** → `true`