API Reference

Settings, toolsets/tools, and the C++ toolbar helpers. The helper classes are static and driven by the toolbar - they are not Blueprint-exposed. Tool names below are the AI-facing names an agent calls through call_tool.

Settings

UCrimsonMCPSettings (module CrimsonCommonEditor) - Project Settings -> Crimson -> Crimson MCP.

Member	Type	Default	Description
`bEnableCrimsonMCP`	`bool`	`false`	Master switch for all Crimson MCP tooling. Read at startup; change requires an editor restart.
`IsEnabled()`	`static bool`	-	Convenience gate every Crimson editor module calls before registering tools.

UCrimsonEditorUtilitiesSettings (module CrimsonEditorUtilities) - Project Settings -> Crimson -> Crimson Editor Utilities.

Member	Type	Default	Description
`bEnableSaveGameDeleter`	`bool`	`true`	Registers the Delete Save Game toolbar button at startup.
`CommonEditorMaps`	`TArray<FSoftObjectPath>`	empty	Maps shown in the Common Maps dropdown. Empty hides the button.

MCP toolsets and tools

Three UToolsetDefinition subclasses registered by CrimsonEditorUtilities when Crimson MCP is enabled. Errors are reported to the agent via a script error.

Toolset	Tool	Description
`CrimsonSourceToolset`	`ReadFile`	Reads a text file in the project or engine tree and returns its contents (path must stay inside those roots).
`CrimsonSourceToolset`	`ListFiles`	Lists files in a project directory, with optional extension filter and recursion.
`CrimsonPluginToolset`	`ListPlugins`	Summarizes every plugin under the project Plugins folder: name, description, and module types.
`CrimsonPluginToolset`	`ValidateDependencies`	Audits all `*.Build.cs` for the cardinal rule (no Crimson-to-Crimson deps except CrimsonCommon / CrimsonSaveSystem).
`CrimsonPluginToolset`	`ScaffoldPlugin`	Generates a complete new Crimson plugin from template, applying the project conventions.
`CrimsonAssetToolset`	`FindAssets`	Queries the Asset Registry for assets of a UClass (including Blueprint subclasses).
`CrimsonAssetToolset`	`InspectAsset`	Loads an asset by package path and returns every UPROPERTY value.
`CrimsonAssetToolset`	`CreateAsset`	Creates a DataAsset or Blueprint asset in the Content Browser.
`CrimsonAssetToolset`	`SetAssetProperty`	Sets one UPROPERTY on an asset (Blueprint CDO for Blueprints) and saves it.
`CrimsonAssetToolset`	`FindTags`	Lists registered GameplayTags matching a prefix.

Names come from reflection

A toolset's name is its UToolsetDefinition class name and a tool's name is its function name; agents call them as Toolset.Tool. Confirm the exact live names with list_toolsets / describe_toolset.

Toolbar helpers (C++, static)

Class	Function	Description
`FCrimsonMCPToolingUtility`	`CanShow()`	True when not in PIE; drives the Crimson MCP button's visibility.
`FCrimsonMCPToolingUtility`	`GetDropdown()`	Builds the Crimson MCP dropdown (master switch, Epic plugins, toolset visibility).
`FCrimsonSaveGameDeleteUtility`	`HasPlayWorld()` / `HasNoPlayWorld()`	PIE-session checks used to gate the Delete Save Game button.
`FCrimsonSaveGameDeleteUtility`	`DeleteDirectory_Clicked(RelativePath)`	Deletes a sub-directory under `Saved/SaveGames/`.
`FCrimsonSaveGameDeleteUtility`	`DeleteSaveFile_Clicked(RelativePath)`	Deletes a single `.sav` file.
`FCrimsonSaveGameDeleteUtility`	`GetSaveFilesDropdown()`	Builds the hierarchical Delete Save Game dropdown.
`FCrimsonCommonMapsUtility`	`CanShowCommonMaps()`	True when not in PIE and at least one map is configured.
`FCrimsonCommonMapsUtility`	`GetCommonMapsDropdown()`	Builds the Common Maps dropdown from `CommonEditorMaps`.

Authoring your own MCP tools

To add MCP tools to a different Crimson plugin, use the shared base in CrimsonCommonEditor - see CrimsonCommon -> How-To: Add MCP Tools to a Plugin. Always gate registration on UCrimsonMCPSettings::IsEnabled() so the master switch keeps cascading.