First session: a quick start
The goal of this first session is a reviewed plan for one small change. Installation, downloads and game setup may take longer than a few minutes.
- Install for your agent and confirm
um --helpworks. - Launch the agent in your working directory. For a clone installation, start inside the clone.
- Ask it to load mod-any-game, check prior field notes and run recon with
um scan. If it needs a game path, have it consultum scan --help. - Choose one simple target: for example, a small item change in a game with a known loader.
- Review the proposed route, backup location and rollback plan. Approve only the actions you understand.
A starter prompt you can adapt
Use the mod-any-game skill to inspect my owned game at [GAME DIRECTORY].
Search existing field notes, run recon, and propose one small mod.
Explain the engine, version, loader, save location and rollback plan.
Do not modify game files or saves yet. Ask before installing loaders,
driving input or publishing anything.This is a suggested prompt, not a command or a tested mod recipe. Replace the bracketed path with your actual directory.
The complete Universal Modder workflow
The upstream mod-any-game skill follows a ten-stage loop. The checkpoints below turn that loop into a practical tutorial. They are editorial guidance, not claims that this site has completed the session.
Search existing knowledge
Look for a field note for your game before asking the agent to discover everything again. Compare the recorded game version, loader and platform with yours. A matching title with a different build is a clue, not proof of compatibility.
Checkpoint — A list of relevant notes and the differences from your setup.
Inspect the game and choose a route
Have the agent identify the engine, version, managed or native code, anti-cheat, installed loaders and save folders. Ask why it prefers one route over alternatives. Review its MODDING_PLAN.md before any installation or patching.
Checkpoint — A written plan naming the intended change, route, prerequisites and unsupported actions.
Set up a safe working environment
Locate the saves before changing them. Use a separate test world or profile where possible, and keep generated assets and intermediate work separate from your original game installation. Ask the agent to explain how a backup would be restored.
Checkpoint — A recoverable backup and a clear rollback procedure.
Read the relevant code
Direct the agent to investigate the real behavior it needs to change, rather than guessing class names or formats. Keep decompiled output out of the mod repository and any published package. The required investigation depends on the game’s modding interfaces.
Checkpoint — An explanation of the code or data responsible for the change, with a concrete integration point.
Build the smallest working change
Make one minimal feature load successfully before adding a larger system. For a weapon idea, start with one item that appears and behaves predictably. Avoid beginning with the entire multi-weapon showcase.
Checkpoint — A small buildable change and a way to recognize it in the game.
Generate and prepare assets
Generate only the assets the slice needs. fal operations require a key and may cost money; local ComfyUI can serve image workflows. Convert output to the engine’s required size, transparency, palette and frame layout. Blender is needed when rendering a 3D model into sprites.
Checkpoint — Assets in the format the game actually expects, with provenance recorded.
Verify in the running game
A successful compile is not an in-game test. Load the mod in a disposable save or world and check the intended behavior. Look for crashes, incorrect frame layouts, input problems and unwanted save changes. Ask the agent to obtain permission before driving mouse or keyboard input.
Checkpoint — Observed game behavior and an honest record of what has and has not been verified.
Record evidence or a showcase
Once the feature works, capture the relevant behavior. Check that video frames and game audio are present before editing. The upstream Windows recording tools are not a promise that the same capture route works on every platform.
Checkpoint — A useful screenshot or recording, with any capture problems documented.
Package only distributable files
Package the mod for its loader or platform. Exclude game files, decompiled output, secrets and unrelated working files. Run the publish checks, then review the package yourself. A clean automated check is one input to review, not permission to distribute third-party material.
Checkpoint — A reviewed package, installation instructions and credits; publication still needs approval.
Write a field note
Record the exact game and tool versions, route, verification and the problems you encountered. Useful notes connect each symptom to a cause and a fix. Validate the note and ask before opening a public pull request.
Checkpoint — A reusable account that distinguishes completed tests from assumptions.
um CLI: commands for the workflow
Use this map to find the relevant tool. Check help for your installed version before choosing options; no example output here is presented as an actual run.
um --help
um scan --help
um backup --help
um publish check --help| Command family | Use in the workflow |
|---|---|
um scan | Inspect installations and candidate routes. |
um kb | Search prior notes and prepare your own. |
um backup | Snapshot, compare and restore save directories. |
um fal | Generate assets using hosted services. |
um comfy | Use a local ComfyUI image workflow. |
um sprite | Prepare sprites and frame layouts. |
um render3d | Render a 3D model into game-camera sprite views. |
um win | Windows game capture and process/input tools. |
um video | Prepare and edit recordings. |
um publish check | Check a package for files that should not ship. |
One upstream knowledge-search example:
um kb search "grand theft auto"A first-mod exercise: start smaller than the showcase
Terraria’s Fal Arsenal is a useful code reference for a tModLoader route. It is not a guarantee that asking for the same weapons will reproduce the example automatically.
- Read the example’s requirements and build instructions. It describes a single-player tModLoader setup; multiplayer is not tested.
- Use a spare world and character. Confirm the agent has located the save folder and can explain its backup plan.
- Ask for one small item or weapon, using the example as a reference rather than copying the whole arsenal.
- Get the minimal item building and loading before generating a custom sprite.
- Verify the sprite, item behavior and save impact in the game; document any version differences.
How game mashups differ from a first mod
A content port brings selected material into another game. A passthrough connects two running games and composites their views. Other projects may integrate a simulation or a decompilation-based library. These approaches have different requirements and cannot be reduced to a single “merge games” command.
The Minecraft × GTA V example uses a Fabric mod, a ScriptHookV component and a ReShade add-on. Camera and gameplay events are exchanged locally; frame data is composited against GTA’s depth buffer. It targets GTA V Legacy story mode, not Enhanced or GTA Online.
Read the version-specific mashup instructions ↗. Treat this as a deeper project after you can build and verify a small mod.
Tutorial questions
Does it require programming knowledge?
The agent can help with code, but you still need to review its plan, install prerequisites and judge whether the game behaves correctly. Complex routes can require substantial debugging.
What if the agent cannot find a workable route?
Ask it to document what it checked and stop before risky changes. Look for a game-specific loader or modding community reference. Do not treat missing evidence as permission to guess.
When is a mod finished?
When the intended behavior is verified on a stated setup, rollback is understood, the package is reviewed and limitations are recorded. Compiling alone is not sufficient.
Can the agent publish automatically?
The upstream rules require approval before publication, including PRs. Review contents, credits and the verification statement first.