sprite-editor

name	sprite-editor
description	Edits Unity sprite properties by generating C# editor scripts using ISpriteEditorDataProvider APIs. Handles sprite rectangles, borders, pivots, outlines, and slicing operations (automatic, grid, isometric). Use when working with sprite assets, sprite sheets, texture atlases, or sprite slicing.
modes	["agent","ask"]

Sprite Editor

Sprite metadata (rects, borders, pivots, outlines) lives inside the importer, not in a file you can edit — reaching it means running C# through a live Editor.

The unity-cli skill owns getting you there — installing the CLI, confirming a connected Editor, adding the project's com.unity.pipeline package, telling a genuinely absent Editor apart from one stuck in Safe Mode, and discovering the Editor's command catalog. Follow it first; don't re-derive any of it here.

Two things it can't know for you:

• You need eval in particular, not just a reachable Editor. Confirm it appears in the catalog — its presence depends on the Pipeline package version, not on the CLI.
• Never hand-edit a .meta file to change sprite metadata. The importer owns that data and the capability checks below exist to prevent corruption, so an unreachable Editor is a stop, not a cue to improvise.

Run C# through the connected Editor with the eval command. Discover its parameter shape from unity command --format json rather than assuming one — the inline form is unity command eval --code '<snippet>', and some Pipeline versions also register eval_file for running a snippet from a file. Check the catalog before reaching for eval_file; it is frequently absent. unity command defaults to a 30 second timeout.

Generates C# editor scripts to manipulate Unity sprites using ISpriteEditorDataProvider. Works with TextureImporter, PSBImporter, and custom importers.

Passing C# to eval

eval compiles a statement block, not a file. Two consequences, both of which cause a compile error rather than a warning:

• No using directives. The compiler reads using UnityEngine; as a resource-disposal statement and rejects it (CS0210).
• Types must be fully qualified. A bare AssetDatabase or Volume does not resolve (CS0246 / CS0103), and a bare Object is ambiguous with object (CS0104).

Where a snippet below is written as a file — with usings, for readability, or because it is meant to be saved into the project — qualify the types before passing it to eval.

Workflow

All generated scripts must follow the Safe Core Pattern in references/templates.md, which includes MANDATORY capability checks. NEVER attempt operations if capability checks fail - this prevents data corruption. After execution, verify results in Unity console and Project window.

Common Operations

Modify Name/Rect/Border/Pivot: Update corresponding SpriteRect fields (see scripts/SetPivotExample.cs for pivot examples)

• Requires: EditSpriteName, EditSpriteRect, EditBorder, or EditPivot

Add/Remove/Slice: Create or filter SpriteRect array (see references/background.md for Unity 2021.2+ requirements)

• Requires: CreateAndDeleteSprite

Set Outlines: Get ISpriteOutlineDataProvider → Call SetOutlines() with GUID + Vector2 arrays

Important Notes

• Do NOT use AssetPostprocessor or MenuItem patterns
• Generate standalone snippets only — no AssetPostprocessor, no MenuItem
• Enum assignments: Always use enum values and cast to numeric types. Never use raw numbers.
  • ✅ Correct: (int)SpriteAlignment.Center
  • ❌ Wrong: 1 (magic number)