s&box

Tools

x_open_scene

Make a scene the active editor tab, opening it from its asset path if it isn't open yet. Accepts a scene name or resource path as list_scenes reports them.

Why it exists: the stock toolset can read and list background scenes but can't switch which one is active, and every mutating tool (set_component, save_scene, undo) targets the active scene. Worse, an edit aimed at a background scene mutates the object but the dirty flag lands on the active tab — the background scene reloads from disk on focus and the edit is silently lost. Upstream: issue #11637, PR #11638 (open).

Explicit no-op message when the scene is already the active tab.
Refuses during play mode — play_stop first.
Refuses the running game session (it has no tab to switch to).

x_create_scene

Create, save, and activate a new empty scene at a project-relative .scene path beneath scenes/diagnostics/. The optional name defaults to the destination file name.

Refuses play mode, absolute or traversing paths, paths outside the diagnostics folder, wrong extensions, and existing destinations.
Saves directly through the editor asset system without a modal or file picker.
Leaves every existing tab—including unsaved work—unchanged.
Removes its temporary unsaved session and any partial asset if creation fails.

x_editor_status

What the editor is doing right now, from the editor's point of view: active scene tab name and path, unsaved-changes flag, open tab count, project ident, play/pause state.

Why it exists: the built-in editor_status reports the game scene handle, not the active editor tab — while editing it returns a placeholder name ("Scene") and a null path, and its dirty flag can describe a different scene than its name. Upstream: issue #11639, PR #11640 (closed unmerged).

x_editor_status reads SceneEditorSession.Active — the same source list_scenes uses — so the two always agree.

Fields the built-in reports that this tool deliberately omits (tool count, compile status, engine paths): they come from engine-internal API a library can't reach, and the built-in editor_status still reports them correctly — use both.

x_set_network_mode

Set an active-scene game object's saved networking mode to Never, Object, or Snapshot by GUID. Refuses play mode and missing/background objects, records one undo step, and returns the resulting mode.

x_camera_screenshot

Render a scene camera to an image with UI text intact. Same arguments as the built-in camera_screenshot — camera (a CameraComponent id, its game object's id, or empty for the scene's main camera), width, height, includeUi — so it's a drop-in swap.

Why it exists: the built-in camera_screenshot renders every Razor text label as a flat gray rectangle at any size other than the live viewport's. Upstream: issue #11585. Engine root cause: CameraComponent.ResizeUI relayouts each screen panel for the offscreen size but omits RootPanel.BuildDescriptors(), so labels resized by that relayout release their text texture while the render descriptors still point at the dead one — ScreenshotService has the correct sequence (PreLayout/CalculateLayout/PostLayout/BuildDescriptors).

In play mode x_camera_screenshot sidesteps it by capturing at exactly the current screen size, where the relayout changes no panel's size and no texture is released, then downscaling the capture to the requested dimensions. In edit mode there is no game viewport, so no live screen-size UI exists whose text textures a relayout could destroy, and it renders directly at the requested size — full detail, no resize step. Either way it works wherever camera_screenshot does.

x_camera_look_at

Aim a camera at a world-space point with the engine's Rotation.LookAt rather than requiring callers to derive Euler angles. Arguments are camera (a CameraComponent or camera game-object GUID), target (x,y,z), and optional up (x,y,z, default 0,0,1). The camera must belong to the active editor scene.

The operation rejects coincident camera/target positions and zero up vectors, records one undo step, and returns the resulting position, target, and angles.

Network and local instances

Seven editor-only tools expose network state and safely manage local clients:

x_network_status — read the active session and privacy-limited connection rows.
x_network_start_hosting — start hosting through the supported editor path.
x_network_disconnect — disconnect without terminating owned clients.
x_network_spawn_instance — launch a fixed local client in a private Windows Job Object. No arbitrary executable, environment, working directory, or arguments.
x_network_instances — list only clients launched by this library during the current hotload lifetime.
x_network_terminate_instance — terminate an owned process tree using its PID and exact LaunchedAt token. Default mode requests a graceful close before forcing the private job; abrupt=true skips directly to forced termination.
x_network_migrate_to_new_instance — currently refuses before launching anything. Installed engine build 26.09.08e selects migration successors through Steam lobby membership, which synthetic local clients cannot satisfy, and exposes no supported targeted-handoff API.

Ownership is in-memory and handle-based. The library starts each child suspended, assigns it to a private Job Object, captures its exact creation identity, and only then resumes it. It never reconstructs ownership from process enumeration or accepts a PID alone. Hotloading or restarting the library deliberately resets ownership without killing surviving clients; close those clients manually afterward.

Network snapshots omit Steam/account identifiers, party data, credentials, chat, and voice. Display names are bounded, stripped of control characters, and redact common Steam identifier formats. LogDirectory identifies the shared engine log root; there is intentionally no instance-log tool because shared logs cannot be attributed safely to one child.

Known issues

The built-in editor_status is still broken while this library only routes around it — a library can't patch engine-assembly tools. Until upstream fixes it, trust x_editor_status or list_scenes.IsActive, not editor_status's scene fields.
Tool errors arrive with a full .NET stack trace appended after the message. That's the engine MCP server's error formatting (its own tools do the same); the first line is the actionable part.
x_open_scene can't target a never-saved scene by path (it has no resource path yet) — use its name.
x_camera_screenshot output detail is capped at the live viewport's resolution in play mode: it captures there and resizes, so a requested size larger than the viewport is interpolation, not extra detail. Aspect ratio still follows the requested size. Edit mode renders at the requested size directly and isn't capped.
Adding this library to a project doesn't take effect in an already-running editor: package mounting happens at project load, only source edits hotload. Restart once.

Tools

Known issues

Package

Tags