Guide · Agent skill
How to use the test-helpers agent skill for game projects
Updated · written with AI from the project's own documentation and checked against our catalogue data
The test-helpers skill is an agent skill for Claude Code that writes reusable test utilities for a game project: assertion functions, factory functions that build test objects, and mocks. It is aimed at developers using Godot 4, Unity or Unreal who already have a test framework set up. By the end of this guide you will know what the skill does, how to install it, how to call it, and what it needs and touches on your machine.
Test Helpers GeneratorDonchitos/Claude-Code-Game-Studios · MIT Download the skill Quick start
- 1Confirm your engine and test framework. Make sure project.yaml or technical-preferences names your engine and test framework. If no framework exists yet, run /test-setup first.
- 2Download and unzip the skill. Download the ZIP from this page and unzip it into ~/.claude/skills/ or the project's .claude/skills/ folder.
- 3Start with scaffold. Run /test-helpers scaffold to generate the base helper library on a new project.
- 4Generate helpers for one system. Run /test-helpers with a system name, such as combat, when you start tests for that system.
- 5Review the output. Check the generated helpers against the framework's documentation and confirm they use its assertion calls.
- 6Use the helpers in your tests. Call the helper functions from your test files to replace repeated setup and assertions.
What is an agent skill and what does test-helpers do?
An agent skill is a folder containing a SKILL.md file that gives an AI agent a specific, repeatable task. When the skill is installed, the agent can run it on your project when you ask for it.
test-helpers generates an engine-specific helper library so that your tests repeat less setup code. The helpers are written into the helper folder that your engine's test runner compiles: tests/helpers/ for Godot, Assets/Tests/EditMode/Helpers/ for Unity, and Source/<Module>/Private/Tests/Helpers/ for Unreal.
- Assertion utilities, such as range checks for formula outputs that have bounds in a design doc
- Factory functions that build test objects
- Mocks and stubs for dependencies
- A base helper library (scaffold) or helpers for one named system
Before you install: what the project needs
The skill only works on a supported game engine project (Godot 4, Unity or Unreal). The engine and language must be set in project.yaml or in .claude/docs/technical-preferences.md. If the engine is not configured, the skill stops and tells you to run /setup-engine first.
A test framework must already exist. The source says it is set up by the companion /test-setup skill, for example GdUnit4 for Godot. Without a configured test framework, the skill stops and asks for setup first.
- A supported engine project: Godot 4, Unity or Unreal
- project.yaml or technical-preferences configured with the engine and test framework
- A test framework set up by /test-setup
- Claude Code with the tools Read, Glob, Grep and Write
Install the test-helpers skill
Download the ZIP for this skill from this page. It contains the SKILL.md file. Unzip it into one of two locations: ~/.claude/skills/ to make it available to you across projects, or the .claude/skills/ folder inside a single project to share it with that project.
If you use the Claude apps instead of Claude Code, you can upload the skill under Settings → Capabilities → Skills.
- Personal install: unzip into ~/.claude/skills/
- Project install: unzip into the project's .claude/skills/ folder
- Claude apps: Settings → Capabilities → Skills, then upload
How to run it: commands and arguments
Run the skill with its slash command and an optional argument. The skill accepts a system name, the word all, or the word scaffold. With no argument it runs scaffold if no helpers exist yet, otherwise all.
Run scaffold first on a new project to create only the base helper library. Use a system name when you are starting tests for one part of the game, such as combat.
- /test-helpers scaffold: base helper library only, no system-specific helpers; use this on first run
- /test-helpers combat: helpers for one named system
- /test-helpers all: helpers for every system that has test files
- /test-helpers with no argument: scaffold if no helpers exist, otherwise all
/test-helpers [system-name | all | scaffold]Ask for helpers in natural requests
The source documents the slash command and its arguments. It does not list separate natural-language trigger phrases, so the safest way to start the skill is with the slash command. Once it is running, it reads your existing tests before writing anything, so your requests can stay short.
The skill also runs in an automation mode set by modes.automation (collaborative, guided or autonomous). In collaborative mode it asks before each write; in autonomous mode it logs and proceeds. The mode is read from project.local.yaml, then project.yaml, with collaborative as the default.
What the skill does step by step
The agent first detects the engine and language from your configuration. Next it scans the test folder and reads up to five existing test files to learn your setup, assertion, object-creation and mock patterns. It also reads the systems index and the relevant design documents so the helpers cover real data types and values.
Assertions must go through the configured test framework's assertion API, not bare assert(). The skill is written to look up that API before generating code, and to generate no helper if it cannot confirm the API.
- Reads project.yaml, then technical-preferences, for engine and test framework
- Scans existing tests and matches their style
- Reads design/gdd/systems-index.md and in-scope design documents
- Writes helpers only into the engine's helper root
Safety notes: scripts and network
The skill runs a script. Its configuration step calls yaml-helper.sh with resolve_config, and the skill's bash permission is restricted to that helper for reading config. The listed tools are Read, Glob, Grep and Write.
The skill does not use the network, according to its listing. It writes files only into the engine's helper folder. Review the generated files before committing them, as you would any code.
- Runs scripts: yes, limited to the restricted config-reading helper
- Uses network: no
- Writes: helper files in the engine's helper root
What people use it for
- Creating a base assertion library, such as a range check for formula outputs with defined bounds
- Building factory functions that create test objects for a new game system
- Writing mocks for dependencies in a team's existing test suite
- Reducing repeated setup and teardown code across several test files
Frequently asked questions
How do I install the test-helpers agent skill?
Download the ZIP from this page and unzip it into ~/.claude/skills/ for personal use, or into a project's .claude/skills/ folder. In the Claude apps you can instead upload it under Settings → Capabilities → Skills.
What do I need before using test-helpers?
You need a supported engine project (Godot 4, Unity or Unreal) with the engine configured in project.yaml or technical-preferences, plus a test framework set up by /test-setup. The skill stops and asks for setup if either is missing.
Is test-helpers free to use?
The source lists the licence as MIT. The source does not state any price, so check this page for current terms.
What is the alternative if my project is not Godot, Unity or Unreal?
The helper rules in this skill are specific to Godot, Unity and Unreal, so it is not designed for general-purpose test writing outside game engines. Use a tool built for your language or framework instead.
Why does the skill refuse to generate helpers sometimes?
By design, it will not guess the test framework's assertion API. If it cannot confirm the correct API for your framework, it generates no helper and says so. The Godot example in the skill file is a placeholder, so the agent has to look up the real API, and that lookup may fail or be incomplete.
Why not use plain assert() in the generated helpers?
The skill's rules say a bare assert() halts the run at the first failure, hiding later results, and that it is stripped in release builds, so tests can pass without checking anything. The framework's assertion API records failures and lets the suite continue.
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Our verdict
Use test-helpers if you build games in Godot, Unity or Unreal, already have a test framework, and want consistent helpers across a team's tests. Pick something else if your project has no engine or test framework, or if you need helpers outside game engines. Always review the generated assertion calls, because the skill depends on the agent finding the correct API for your framework.
Download the skill