Universal Modder um CLI.
The command map, explained.

How to read this um CLI reference

The Universal Modder um CLI groups game reconnaissance, asset preparation, automation and publishing checks under one entry point. This reference explains all ten top-level groups and the subcommands present in the reviewed source.

Arguments were checked against the upstream Python parsers on October 11, 2026. Examples below are source-checked, not executed by this site. File-based examples require your own input files. Network and game operations depend on credentials, platform and installed tools.

um --version
um --help
um sprite fit --help

Use --help at the relevant level before running an example on another version. A filename in an example is a local sample name, not a file bundled with this website. Create output folders as needed and keep source files separate.

Install or repair the CLI → · See the complete modding workflow →

um scan — inspect installed games

Read-only game and installation discovery. A game argument is a fuzzy name or directory; --list inventories discovered libraries and --json produces machine-readable output. Engine, loader, anti-cheat and save findings are evidence for planning, not a compatibility certification.

Commands / options: --list; game name or path; --json

um scan --list
um scan terraria
um scan "C:\Games\YourGame" --json

Before running: Needs an installed game for the last two commands. Replace the sample path. Review warnings and the ranked routes before approving changes.

Sources: Parser and implementation ↗

um fal — hosted assets and model tools

Uses fal for image, 3D, audio and video operations. Generation may be billable. Local inputs can be uploaded as part of a request: use only files you intend to send to the service.

Commands / options: image · sprite · edit · rmbg · pixelate · upscale · texture · pbr · model3d · rig · sfx · music · voice · video · run · search · schema · price · result · upload

um fal search "pixel art" --limit 5
um fal sprite "a small copper robot, side view" --out assets/gen --name robot

Before running: The sprite example requires FAL_KEY and service credits. Review the endpoint and cost first. Generated files and a generation manifest are written to the output directory.

Sources: Parser and implementation ↗

um comfy — local image generation

Connects to a running ComfyUI server. status reports connectivity and available checkpoints; image uses the default text-to-image graph; run accepts a workflow exported in API format.

Commands / options: status · image · run

um comfy status
um comfy image "a small copper robot, side view" --sprite --out assets/gen --name robot

Before running: Requires a running compatible server and installed checkpoint. --sprite generates against a plain background and performs a local cutout. --url belongs after the subcommand; COMFYUI_URL can also configure the server.

Sources: Parser and implementation ↗

um sprite — prepare 2D assets

Transforms local images to match an engine’s frame and palette requirements. Use fresh output filenames to avoid overwriting source art. fit uses nearest-neighbor resizing by default; --smooth selects a different resampling route.

Commands / options: info · cutout · fit · pixelate · palette · sheet · slice · frames · team-mask · seamless · tile-preview · preview · outline · hard-alpha · flip · rotate

um sprite info assets/robot.png
um sprite fit assets/robot.png assets/robot-frame.png --size 32x32
um sprite preview assets/robot-frame.png assets/robot-preview.png --scale 4

Before running: Provide your own assets/robot.png. A preview is for inspection, not the game asset. The command syntax differs for sheet, slice and frames; see the table below.

Uppercase words above are placeholders. team-mask also writes a mask file; tile-preview is for checking repeated textures. hard-alpha thresholds transparency and can lose soft edges.

Sources: Parser and implementation ↗

um render3d — render a GLB to sprites

Runs Blender to render a local GLB into sprite views. Choose a camera preset suited to the target game and verify orientation and scale in-game; an attractive render is not proof of engine compatibility.

Commands / options: Camera presets: aoe2 · iso8 · trueiso · topdown · side · turntable

um render3d assets/robot.glb assets/robot-views --preset iso8 --canvas 128

Before running: Needs your GLB and a Blender installation. Input and output are positional arguments. --anims specifies animation/frame settings; --shadows adds a shadow pass.

Sources: Parser and implementation ↗

um win — Windows game tools

Windows/WSL operations for window capture, recording, input, processes and registry access. These are not cross-platform substitutes for native game tools. Process listing is a useful read-only first check.

Commands / options: setup · ps · kill · launch · shot · record · drive · reg

um win ps Terraria
um win shot captures/terraria.png --exe Terraria.exe

Before running: The screenshot needs a matching running game window and a writable captures folder. setup installs/downloads capture prerequisites. Ask before drive or installs; kill takes an exact PID. Registry and launch operations can change the environment.

Sources: Parser and implementation ↗

um video — inspect and edit recordings

Use probe and contact to check captured material before producing a finished showcase. mux combines the recorder’s video, raw audio and metadata. compile consumes an edit-decision-list JSON file.

Commands / options: probe · contact · first-frame · beats · mux · compile

um video probe takes/demo.mp4
um video contact takes/demo.mp4 takes/contact.jpg --every 2 --cols 6

Before running: Supply a real input recording and ffmpeg tooling. A contact sheet writes a frame grid. first-frame prints an estimated gameplay start time; beats analyzes an audio file.

Sources: Parser and implementation ↗

um backup — snapshot, compare and restore

Creates save-folder snapshots, lists them and compares changes. Resolve the exact save location first. Restore is a write operation; inspect a diff and keep another copy before using it.

Commands / options: create · list · diff · restore

um backup create "./test-saves" --name first-mod
um backup list first-mod
um backup diff first-mod

Before running: Create a disposable test-saves folder with sample files before trying this sequence. It writes a named backup, lists its snapshots and compares against the saved source location. Avoid --clean on real saves unless you understand its deletion behavior.

um backup restore first-mod --to "./restored-test-saves"

This optional restore writes into a separate destination for a recovery check. Review the prompt. --clean can remove files added since the snapshot; --yes skips confirmation. Neither is needed for the example.

Sources: Parser and implementation ↗

um publish check — review a distributable mod

Scans a local mod folder for disallowed game files, decompiled output and exposed secrets. Supplying the game installation directory adds copied-file checking. Review licenses and the package yourself even when checks pass.

Commands / options: check MOD_DIRECTORY [--game GAME_DIRECTORY]

um publish check ./dist/my-mod

Before running: Needs a prepared mod directory. The tool prints FAIL/WARN/PASS information; failures return a nonzero exit status. A warning-only result can still need attention. This command checks a package; it does not publish it.

Sources: Parser and implementation ↗

um kb — shared field notes

Finds prior work and manages structured knowledge notes. Searches can use a clone or a cached remote copy; creating and indexing notes need a writable knowledge directory.

Commands / options: search · show · new · check · index · sync · pr

um kb search "grand theft auto"
um kb new --game "Terraria" --title "A small weapon mod" --agent "Your agent label"

Before running: Search may access the network to populate the cache. Run new in an upstream clone or use its --root option. Fill and validate the generated note; PR creation is a separate approved action.

show displays a note, check validates it, index rewrites the local index, and sync refreshes the cached upstream copy. pr previews its Git operations by default; adding --yes branches, commits, pushes and opens a PR. Only do that after reviewing the actual note and receiving permission.

Sources: Parser and implementation ↗

Common command mistakes

Missing CLI

Verify PATH in the agent’s shell; see installation troubleshooting.

Unknown flag

Use the exact subcommand’s help. For example, --size belongs to sprite fit, while render3d uses --canvas.

Wrong file path

Resolve paths from your current directory. Windows and WSL paths are not interchangeable in every tool.

Blank result

Check errors, output locations and prerequisites rather than treating command completion as in-game verification.

Unexpected cost

Inspect the model endpoint and pricing before hosted generation. A local sprite transformation and a fal generation have different effects.

Claude Code setup →Codex setup →