ui

Unity Open MCP — UI (uGUI) Extension

Skill for AI agents driving Unity uGUI (Canvas / elements / layout groups / element modify) in a project through the unity-open-mcp MCP server.

This domain is embedded in the bridge and opt-in. Its tools use the built-in UI module (Canvas / CanvasScaler / GraphicRaycaster / Image / Text / Button / Slider / Toggle / InputField / layout groups / EventSystem from UnityEngine.UI + UnityEngine.EventSystems) — no Unity package install is required, and they compile into every bridge build. Its tool group is hidden from ListTools until the connected session activates it. TextMesh Pro (TMP_Text) is optional and detected at call time — when absent, ui_element_add with element_type=TMP_Text returns a structured tmp_package_required error (no silent legacy-Text fallback).

Preconditions

• Unity Editor is open with the target project.
• unity_open_mcp_ping returns connected: true.
• The ui tool group is activated — call unity_open_mcp_manage_tools(action="activate", group="ui") before invoking any UI tool. Fresh sessions start with two default-on groups (core and gate-and-verify); activate the other groups you need on demand. Because uGUI is built-in, capabilities always reports the ui group as available: true (no domainDefine).

Tool prefix

One prefix, four tools, all in the ui group:

• unity_open_mcp_ui_canvas_add — add a Canvas (+ CanvasScaler + GraphicRaycaster) to a host GameObject or as a new scene root, and ensure an EventSystem exists in the open scene(s). Mutating.
• unity_open_mcp_ui_element_add — add a uGUI element (Text / TMP_Text if TMP is present / Image / Button / Slider / Toggle / InputField) as a child of a parent RectTransform. Mutating.
• unity_open_mcp_ui_layout_group_add — add a HorizontalLayoutGroup / VerticalLayoutGroup / GridLayoutGroup to a parent. Mutating.
• unity_open_mcp_ui_element_modify — typed patch on a uGUI component (Selectables, Graphic color / raycastTarget, LayoutElement preferred sizes, Text / TMP_Text text). Mutating.