Use the installed CLI; on macOS it is inside the app bundle, commonly /Applications/Aseprite.app/Contents/MacOS/aseprite. Check --version and --help before relying on version-specific options.
Keep the editable .aseprite or .ase source separate from runtime exports and never save over it while exporting. For repeatable edits to layers, frames, tags, or palettes, run a Lua script with --batch --script <FILE>. Preserve existing layers, tags, slices, and frame durations outside the requested change.
Export
Match the engine's loader first: packed atlases need per-frame rectangles, while fixed-grid loaders need uniform cells (--sheet-type rows, no --trim). A packed export with full metadata:
<ASEPRITE> --batch <SOURCE.aseprite> --sheet-type packed --sheet <OUT.png> --data <OUT.json> --format json-array --list-tags --list-slices
The CLI overwrites the --sheet and --data targets without asking.
Verify
Parse the JSON and check that every frame rectangle lies inside the sheet and every tag references existing frames. Load the sheet through the engine's real loader and check frame timing, transparency, pivots, and tag playback in the running game.