# Edit Scene > >- - **Type:** Skill - **Install:** `agentstack add skill-nowsprinting-unity-coding-skills-edit-scene` - **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior - **Seller:** [nowsprinting](https://agentstack.voostack.com/s/nowsprinting) - **Installs:** 0 - **Category:** [Agent Skills](https://agentstack.voostack.com/c/agent-skills) - **Latest version:** 0.1.0 - **License:** Unlicense - **Upstream author:** [nowsprinting](https://github.com/nowsprinting) - **Source:** https://github.com/nowsprinting/unity-coding-skills/tree/master/skills/edit-scene ## Install ```sh agentstack add skill-nowsprinting-unity-coding-skills-edit-scene ``` Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent. ## About Guide for creating and editing Unity scene files in Unity projects. ## Rules - Do not directly Edit or Write `.unity` or `.prefab` files. Instead, write an editor script under `Assets/Editor/` and execute it in Unity to create or update the scene or prefab — those carry GameObject/Prefab-instance structure that is unsafe to author by hand. - **Editor scripts must always end with `EditorSceneManager.SaveScene` (or `PrefabUtility.SaveAsPrefabAsset` for prefabs).** Treat "no dirty scenes/assets at script exit" as a hard postcondition. - Scene: `EditorSceneManager.SaveScene(scene, path)` (new) or `EditorSceneManager.SaveScene(scene)` (existing). The return value is `true` on success. - Prefab: `PrefabUtility.SaveAsPrefabAsset(go, path)`. When editing via `LoadPrefabContents`, always pair with `SaveAsPrefabAsset` → `UnloadPrefabContents`. - When the script also creates side-effect assets (Materials, ScriptableObjects, etc.), call `AssetDatabase.SaveAssets()` after the per-object saves to flush pending writes. - Before running an editor script, check if the editor is in Play Mode using the `mcp__jetbrains__unity_play_control` tool. If it is, stop it first — Play Mode may skip recompilation, leaving stale code active. - After modifying code, confirm compilation success using the `mcp__jetbrains__get_unity_compilation_result` tool before running. - **To determine which assembly an editor script belongs to**, run `${CLAUDE_SKILL_DIR}/scripts/resolve-assembly.sh `. It walks up directories to find the nearest `.asmdef`; if none is found, it falls back to `Assembly-CSharp-Editor` (path contains `/Editor/`) or `Assembly-CSharp`. - **Prefer the `mcp__jetbrains__run_method_in_unity` tool (MCP Server Extension for Unity) for execution.** Define a `public static` method in the script (adding `[MenuItem("Tools/...")]` is optional) and invoke it directly via `mcp__jetbrains__run_method_in_unity`. Only fall back to `execute_run_configuration` or other alternatives when `mcp__jetbrains__run_method_in_unity` is unavailable. - For uGUI buttons and text, use the **legacy variants** (`UnityEngine.UI.Button` / `UnityEngine.UI.Text`). Do not use TextMeshPro unless the user explicitly requests it. - Apply context-menu-equivalent defaults when creating uGUI components (see Resources below). - Give every GameObject the user operates (buttons, toggles, input fields, etc.) a name that makes its hierarchy path unique within the scene/prefab. Otherwise, automated tests cannot identify the GameObject. ## Gotchas - **Never call two Unity Editor tools in parallel.** `mcp__jetbrains__unity_play_control`, `mcp__jetbrains__get_unity_compilation_result`, `mcp__jetbrains__run_method_in_unity`, and `mcp__jetbrains__run_unity_tests` must be called strictly one at a time — always wait for each call to return before making the next one. Calling them concurrently causes domain-reload conflicts that result in "canceled" or "did not connect within 30 seconds" errors. - **When a Unity Editor tool returns `error` or `canceled`, wait 10 seconds before retrying.** Domain reload typically takes several seconds; immediate retry hits the same in-flight reload and fails again. Do not switch tools in the meantime (e.g., calling `mcp__jetbrains__unity_play_control` to verify state) — that just compounds the multiplexed calls. If the same tool returns `error` or `canceled` on two consecutive attempts (with the 10-second wait between them), stop and consult the user instead of retrying further. - **`.meta` files follow an asymmetric commit rule.** Never create them manually — Unity generates them automatically. Scene/prefab files (`.unity`, `.prefab`) and their referenced assets (materials, SOs, etc.) must be **committed** (required for GUID resolution); editor scripts (`Assets/Editor/*.cs`) and their `.meta` must **not** be committed — orphaned metas break the other checkout if the script is absent. Do not delete them; leave them for the user to remove manually. Do not add them to `.gitignore`; the user excludes them at commit time. ## Scene lifecycle - **New scene**: First determine whether the scene will be loaded additively or as a single scene, then choose the setup accordingly. - **Additive** (`LoadSceneMode.Additive`): `EditorSceneManager.NewScene(NewSceneSetup.EmptyScene, NewSceneMode.Single)` — no camera or light needed. - **Single** (`LoadSceneMode.Single`): `EditorSceneManager.NewScene(NewSceneSetup.DefaultGameObjects, NewSceneMode.Single)` — Main Camera and Directional Light are included automatically; do not add a camera manually. - In both cases, place additional GameObjects via `ObjectFactory.CreateGameObject` and save with `EditorSceneManager.SaveScene(scene, "Assets/YourFeature/Scenes/XxxScene.unity")`. - **Edit existing scene**: `EditorSceneManager.OpenScene(path, OpenSceneMode.Single)` → make changes → `EditorSceneManager.SaveScene(scene)`. - **New prefab**: build the GameObject hierarchy in memory, then save with `PrefabUtility.SaveAsPrefabAsset(go, "Assets/YourFeature/Prefabs/XxxPrefab.prefab")`. - **Edit existing prefab**: open with `PrefabUtility.LoadPrefabContents(path)` → modify → `PrefabUtility.SaveAsPrefabAsset(root, path)` → `PrefabUtility.UnloadPrefabContents(root)`. - Use `ObjectFactory.CreateGameObject` / `ObjectFactory.AddComponent` so Undo history and Presets are applied automatically. - Parent child objects with `transform.SetParent(parent, worldPositionStays: false)`. ## Resources - Before writing or modifying any editor script that creates or manipulates uGUI components: Read `${CLAUDE_SKILL_DIR}/resources/ugui.md` ## Troubleshooting - The `mcp__jetbrains__run_method_in_unity` tool is not available or fails with a connection error: Read `${CLAUDE_SKILL_DIR}/resources/troubleshooting-run-method-in-unity.md` ## Source & license This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code. - **Author:** [nowsprinting](https://github.com/nowsprinting) - **Source:** [nowsprinting/unity-coding-skills](https://github.com/nowsprinting/unity-coding-skills) - **License:** Unlicense Install and usage instructions live in the source repository linked above. ## Pricing - **Free** — Free ## Security capabilities Automated source analysis of v0.1.0 — what this tool can access: - **Network access:** no - **Filesystem access:** no - **Shell / process execution:** no - **Environment & secrets:** no - **Dynamic code execution:** no *"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.* ## Versions - **0.1.0** — security scan: passed — Imported from the upstream source. ## Links - Listing page: https://agentstack.voostack.com/l/skill-nowsprinting-unity-coding-skills-edit-scene - Seller: https://agentstack.voostack.com/s/nowsprinting - Browse the marketplace: https://agentstack.voostack.com/browse --- Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.