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UECopilot Plugin Documentation

Version: 1.0.0 | Last Updated: 2026-05-08 Target Engine: Unreal Engine 5.7

1. Plugin Overview

1.1 What is UECopilot?

UECopilot is an AI-assisted development plugin integrated into the Unreal Engine 5 editor. Through the Blueprint MCP Server (Blueprint Model Context Protocol Server, UEMCP), it exposes UE5's Blueprint data structures and editing operations as HTTP APIs, allowing AI models (such as Claude, GPT, etc.) to directly read, understand, create, and modify Blueprint assets.

One-sentence summary: UECopilot enables AI to "understand" your Blueprints and operate them for you like an experienced TA/programmer.

1.2 Operation Mode

Mode	Startup Method	Use Case	Features
Editor Mode	Automatically loaded when UE5 editor starts	Daily development	Editor and MCP service coexist, real-time operation

2. Core Capabilities Overview

UECopilot's UEMCP module has been comprehensively analyzed and currently provides 80+ MCP tools, covering the following 9 major capability domains:

Capability Domain	Tool Count	Capability Rating
Blueprint Reading & Retrieval	8	Stable
Blueprint Graph Editing & Node Operations	15	Stable
Blueprint Variables & Type System	6	Stable
Function/Parameter Management	4	Stable
Blueprint Structure & Metadata	9	Stable
Material System	18	Mature
Animation Blueprint System	12	Developing
Safety & Snapshot System	6	Stable
Asset Discovery & Reflection	5	Mature
Unreal Python API (AI + World Building)	Level Automation (Procedural Tools)	Planned

Capability Rating Descriptions:

Mature: Full tool functionality, edge cases well handled, SEH protection in place

Stable: Core paths usable, some boundary conditions to watch for

Developing: Basic capabilities available, advanced scenarios need improvement

2.1 What Can It Do? (Scenario Descriptions)

Scenario 1: AI-Assisted Blueprint Debugging

User: "Help me check if there are any disconnected pins in this Blueprint"
AI → calls find_disconnected_pins → returns all unconnected input pins
AI → provides fix suggestions

Scenario 2: AI-Assisted Blueprint Refactoring

User: "Change all function calls referencing OldClass to NewClass"
AI → calls replace_function_calls (supports dry_run preview) → executes replacement

Scenario 3: AI-Assisted Material Creation

User: "Help me create a material with a normal map and color adjustment"
AI → create_material → add_material_expression (TextureSample, Multiply, etc.)
     → connect_material_pins → completes the material network

Scenario 4: AI-Assisted Animation State Machine

User: "Add an Idle→Run transition in this Anim Blueprint"
AI → add_anim_state → add_anim_transition → set_transition_rule

Scenario 5: Safe Experimentation

User: "I want to modify this function parameter type, but I'm worried about issues"
AI → snapshot_graph (take snapshot first) → change_function_parameter_type → if error, restore_graph

3. System Requirements

Unreal Engine: 5.7+
Operating System: Windows 64-bit (fully tested)
Additional Dependencies: Node.js (for Web UI service, MCP service does not require it)

4. Usage Guide

4.1 Recommended Workflow

The recommended workflow follows four steps: "Preview → Snapshot → Execute → Verify":

Step 1: Preview & Analysis
  ├── Use get_blueprint / get_blueprint_graph to understand current state
  ├── Use search_blueprints to search for relevant nodes
  └── Use check_pin_compatibility to pre-check pin connection feasibility

Step 2: Create Safety Snapshot
  └── Use snapshot_graph to save the current graph state

Step 3: Execute Changes
  ├── Use add_node / connect_pins / delete_node, etc.
  ├── Tools with dryRun parameter should be used for a dry run first
  └── For major changes, use validate_blueprint to check compilation results

Step 4: Verify & Restore
  ├── Use validate_blueprint to verify Blueprint integrity
  ├── Use diff_graph to compare differences before and after changes
  └── If issues arise, use restore_graph to roll back to the snapshot state

4.2 AI Prompt Tips

Good prompt examples:

# Clearly specify the target object
"Add a Print String node to the EventGraph of Blueprint MyCharacter, printing 'Hello'"

# Step-by-step operations
"1. First take a snapshot of MyCharacter's EventGraph
 2. Then change the input parameter type of the MoveForward function from float to double
 3. Finally verify if the Blueprint has compilation errors"

# Query first, then operate
"First list all Blueprints in the project that inherit from Character,
 then tell me their names and paths"

Vague prompts to avoid:

✗ "Help me fix this Blueprint" — Which Blueprint? Fix what?
✗ "Add a feature" — What feature? Where to add it?
✗ "Modify the material" — Which material? Change it to what?

4.3 Usage Notes

MCP service is not head-safe: Although SEH (Structured Exception Handling) protection is used, erroneous operations in extreme cases could still cause the editor to crash. It is recommended to save the project and back up important Blueprints before operating.
All write operations support Ctrl+Z undo: The server wraps each write operation in an Undo transaction, but it is recommended to manually save promptly after continuous operations.
Snapshots are saved to disk: Snapshot files are stored in the Project/Saved/BlueprintMCP/Snapshots/ directory and are not included in project version control. Manual backup is recommended for important operations.
AI model differences in understanding UE terminology: Different AI models may have varying understandings of UE-specific terms (such as "pin connection", "break struct", "event dispatcher"). Please use UE5 official terminology in your prompts.

5. MCP Tools Complete Reference

Note: The following lists all MCP tools that can be directly invoked through AI conversation. Tool names use snake_case convention. You can use these tool names directly in your prompts.

5.1 Blueprint Retrieval & Reading (8 Tools)

Tool Name	Function	Key Parameters
`list_blueprints`	List all Blueprint assets, supports filtering by name and parent class	`filter`, `parentClass`, `type`
`get_blueprint`	Get detailed info of a specific Blueprint (variables, functions, components, etc.)	`name`
`get_blueprint_summary`	Get a brief summary of a Blueprint (same as get_blueprint)	`name`
`get_blueprint_graph`	Get the full structure of a specified graph (EventGraph, FunctionGraph, etc.)	`name`, `graph`
`describe_graph`	Get a pseudocode-style description of a graph (same as get_blueprint_graph)	`name`, `graph`
`search_blueprints`	Search for nodes with specific names in Blueprints	`query`, `path`, `maxResults`
`find_asset_references`	Find all nodes referencing a specified class	`class`, `blueprint`
`search_by_type`	Search for usage of a specific node type in Blueprints	`nodeClass`, `blueprint`, `graph`

5.2 Blueprint Node Editing (15 Tools)

Tool Name	Function	Key Parameters
`add_node`	Add a new node to a specified graph	`blueprint`, `graph`, `nodeType`, `position`
`delete_node`	Delete a node from a graph	`blueprint`, `nodeId`
`duplicate_nodes`	Duplicate one or more nodes	`blueprint`, `nodeIds`, `offset`
`move_node`	Move a node to a new position	`blueprint`, `nodeId`, `position`
`connect_pins`	Connect pins between two nodes	`blueprint`, `sourceNodeId`, `sourcePin`, `targetNodeId`, `targetPin`
`disconnect_pin`	Disconnect all connections of a specified pin	`blueprint`, `nodeId`, `pinName`
`refresh_all_nodes`	Refresh all nodes in a graph (clean up broken references)	`blueprint`
`set_pin_default`	Set the default value of a pin	`blueprint`, `nodeId`, `pinName`, `value`
`get_pin_info`	Get detailed pin info (type, direction, connection status)	`blueprint`, `nodeId`, `pinName`
`check_pin_compatibility`	Pre-check if two pins can be connected	`blueprint`, `sourceNodeId`, `sourcePin`, `targetNodeId`, `targetPin`
`get_node_comment`	Get a node's comment text	`blueprint`, `nodeId`
`set_node_comment`	Set a node's comment text	`blueprint`, `nodeId`, `comment`
`replace_function_calls`	Replace function call target class in Blueprints (supports dry_run preview)	`blueprint`, `oldClass`, `newClass`, `dryRun`
`change_struct_node_type`	Change the struct type of Break/Make struct nodes	`blueprint`, `nodeId`, `structType`

5.3 Blueprint Variable System (6 Tools)

Tool Name	Function	Key Parameters
`add_variable`	Add a new member variable to a Blueprint	`blueprint`, `variableName`, `variableType`, `category`
`remove_variable`	Remove a member variable from a Blueprint	`blueprint`, `variableName`
`change_variable_type`	Change a variable's type (supports dry_run impact analysis preview)	`blueprint`, `variable`, `newType`, `dryRun`
`set_variable_metadata`	Set a variable's metadata (category, description, etc.)	`blueprint`, `variable`, `metadata`
`set_blueprint_default`	Set a Blueprint CDO default property value	`blueprint`, `propertyName`, `value`
`delete_asset`	Delete a specified asset file	`path`

5.4 Function & Parameter Management (4 Tools)

Tool Name	Function	Key Parameters
`add_function_parameter`	Add a parameter to a function/custom event	`blueprint`, `functionName`, `paramName`, `paramType`
`remove_function_parameter`	Remove a parameter from a function/custom event	`blueprint`, `functionName`, `paramName`
`change_function_parameter_type`	Change a function parameter type (supports dry_run preview)	`blueprint`, `functionName`, `paramName`, `newType`, `dryRun`
`reparent_blueprint`	Change a Blueprint's parent class (supports C++ classes and Blueprint classes)	`blueprint`, `newParentClass`

5.5 Blueprint Structure & Metadata (9 Tools)

Tool Name	Function	Key Parameters
`create_blueprint`	Create a new Blueprint asset	`blueprintName`, `packagePath`, `parentClass`, `blueprintType`
`create_graph`	Create a new graph in a Blueprint (EventGraph, FunctionGraph, etc.)	`blueprint`, `graphName`, `graphType`
`delete_graph`	Delete a specified graph from a Blueprint	`blueprint`, `graphName`
`rename_graph`	Rename a graph in a Blueprint	`blueprint`, `oldName`, `newName`
`add_interface`	Add an interface implementation to a Blueprint	`blueprint`, `interfaceName`
`remove_interface`	Remove an interface implementation from a Blueprint (optionally keep functions)	`blueprint`, `interfaceName`, `preserveFunctions`
`list_interfaces`	List all interfaces implemented by a Blueprint	`blueprint`
`add_event_dispatcher`	Add an event dispatcher (supports dispatchers with parameters)	`blueprint`, `dispatcherName`, `parameters`
`list_event_dispatchers`	List all event dispatchers and their parameters for a Blueprint	`blueprint`

5.6 Component System (3 Tools)

Tool Name	Function	Key Parameters
`add_component`	Add a component to a Blueprint's SCS	`blueprint`, `componentClass`, `name`, `parentComponent`
`remove_component`	Remove a component from a Blueprint's SCS	`blueprint`, `componentName`
`list_components`	List all components in a Blueprint's SCS	`blueprint`

5.7 User-Defined Types (4 Tools)

Tool Name	Function	Key Parameters
`create_struct`	Create a user-defined struct asset (supports adding properties)	`assetPath`, `properties`
`create_enum`	Create a user-defined enum asset	`assetPath`, `values`
`add_struct_property`	Add a new property to a struct	`structPath`, `propertyName`, `propertyType`
`remove_struct_property`	Remove a property from a struct	`structPath`, `propertyName`

5.8 Material System (18 Tools)

Material Reading:

Tool Name	Function	Key Parameters
`list_materials`	List all material and material instance assets	`filter`, `type`
`get_material`	Get detailed material info (domain, blend mode, parameter list, referenced textures)	`name`
`get_material_graph`	Get the node connection structure of a material graph	`name`
`describe_material`	Provide a detailed pseudocode description of a material graph	`material`
`search_materials`	Search for expressions in materials	`query`
`find_material_references`	Find materials referencing a specified texture or material function	`texture`, `materialFunction`

Material Writing:

Tool Name	Function	Key Parameters
`create_material`	Create a new material asset (supports domain and blend mode settings)	`name`, `packagePath`, `domain`, `blendMode`
`set_material_property`	Set material top-level properties (domain, blend mode, two-sided, etc.)	`material`, `property`, `value`
`add_material_expression`	Add an expression node to a material graph	`material`, `expressionClass`, `position`
`delete_material_expression`	Delete an expression from a material graph	`material`, `expressionId`
`connect_material_pins`	Connect two pins in a material graph	`material`, `expression`, `pinName`, `targetExpression`, `targetPin`
`disconnect_material_pin`	Disconnect all connections of a specified material pin	`material`, `expressionId`, `pinName`
`set_expression_value`	Set a material expression's parameter value	`material`, `expressionId`, `parameter`, `value`
`move_material_expression`	Move a material expression's position in the editor graph	`material`, `expressionId`, `position`

Material Instances:

Tool Name	Function	Key Parameters
`create_material_instance`	Create a Material Instance Constant (MIC)	`name`, `packagePath`, `parentMaterial`
`set_material_instance_parameter`	Set a material instance's parameter override value	`materialInstance`, `parameterName`, `value`, `type`
`get_material_instance_parameters`	Get all overridable parameters of a material instance	`materialInstance`
`reparent_material_instance`	Change a material instance's parent material	`materialInstance`, `newParent`

Material Functions:

Tool Name	Function	Key Parameters
`list_material_functions`	List all material function assets	`filter`
`get_material_function`	Get detailed information about a material function	`name`
`create_material_function`	Create a new material function asset	`name`, `packagePath`

Material Safety:

Tool Name	Function	Key Parameters
`validate_material`	Compile and validate a material	`material`
`snapshot_material_graph`	Take a snapshot of a material graph	`material`
`diff_material_graph`	Compare differences between a material graph and its snapshot	`material`, `snapshotId`
`restore_material_graph`	Restore a material graph from a snapshot	`material`, `snapshotId`

5.9 Animation Blueprint System (12 Tools)

Tool Name	Function	Key Parameters
`create_anim_blueprint`	Create an Animation Blueprint asset	`name`, `packagePath`, `skeleton`, `parentClass`
`add_state_machine`	Add a state machine to an Anim Blueprint	`blueprint`, `name`
`add_anim_state`	Add an animation state to a state machine	`blueprint`, `stateMachine`, `stateName`
`remove_anim_state`	Remove an animation state from a state machine	`blueprint`, `stateName`
`add_anim_transition`	Add a transition rule between states	`blueprint`, `fromState`, `toState`
`set_transition_rule`	Set the rule Blueprint for a state transition	`blueprint`, `transitionId`, `ruleBlueprint`
`add_anim_node`	Add an animation node to an animation state	`blueprint`, `stateName`, `nodeType`
`set_state_animation`	Set the animation sequence used by a state	`blueprint`, `stateName`, `animation`
`list_anim_slots`	List an Anim Blueprint's slots	`blueprint`
`list_sync_groups`	List an Anim Blueprint's sync groups	`blueprint`
`create_blend_space`	Create a blend space asset (1D/2D)	`name`, `packagePath`, `skeleton`
`set_blend_space_samples`	Set the sample points of a blend space	`blendSpace`, `samples`

5.10 Safety & Snapshot System (6 Tools)

Tool Name	Function	Key Parameters
`snapshot_graph`	Create a Blueprint graph snapshot (saved to disk)	`blueprint`, `graphs`
`diff_graph`	Compare the current graph with a snapshot	`blueprint`, `snapshotId`
`restore_graph`	Restore a Blueprint graph from a snapshot	`blueprint`, `snapshotId`
`find_disconnected_pins`	Find all unconnected input pins in a graph	`blueprint`
`analyze_rebuild_impact`	Analyze the potential impact scope of a Blueprint rebuild	`blueprint`, `changeDescription`
`diff_blueprints`	Compare the graph structure differences between two Blueprints	`blueprintA`, `blueprintB`, `graph`

5.11 Asset Discovery & Reflection (5 Tools)

Tool Name	Function	Key Parameters
`list_classes`	List all available UClasses	`filter`
`list_functions`	List all functions of a specified class	`className`, `filter`
`list_properties`	List all properties of a specified class	`className`, `filter`
`rescan_assets`	Rescan the asset registry, refresh cache	None
`server_status`	View MCP server runtime status and asset statistics	None

5.12 Utility Functions & Safety Mechanisms

Type Resolver (ResolveTypeFromString)

Supported type resolution formats:

Input Format	Example	Resolution Result
Basic Types	`int`, `float`, `bool`, `string`, `text`	Corresponding basic pin types
Object Reference	`object:Actor`	UObject subclass reference
Soft Object	`softobject:Texture2D`	Soft object reference
Class Reference	`class:Actor`	Class reference
Soft Class Reference	`softclass:AnimInstance`	Soft class reference
Struct	`struct:Vector`, `struct:Transform`	Struct pin type
Enum	`enum:ETraceTypeQuery`	Enum byte type
Interface	`interface:BPI_Interact`	Interface reference
Array	`array:int`, `array:object:Actor`	TArray type

SEH Safety Protection (Windows Only)

For high-risk operations (Blueprint compilation, material expression addition, package saving, etc.), the __try/__except Structured Exception Handling (SEH) mechanism is used. This means that even if an operation causes an internal engine crash (such as an access violation), the service will not completely crash, but will instead return an error message.

Undo Transaction Support

All tool calls that modify Blueprints are wrapped in Undo/Redo transactions. This means that when used in the editor, operations executed by AI can be undone with Ctrl+Z.

6. Usage Boundaries & Limitations

6.1 Known Limitations

Category	Description	Impact
Multi-User	The service is designed for single-user; simultaneous multi-user operations are not supported	⚠️ Medium
Network	Only listens on 127.0.0.1, remote access not supported	🔒 Security Design
Version Compatibility	Based on UE5.4+ API, not tested on UE4	⚠️ High
Platform	SEH protection is Windows-only; material system SEH has a dedicated implementation	⚠️ Medium
Hot Reload	Plugin module needs to reconnect after hot reload	⚠️ Low
Large Projects	Ultra-large projects with tens of thousands of Blueprints may take a few seconds for the initial scan	⚠️ Medium
Compilation Safety	Blueprint compilation triggers the full compilation chain; complex Blueprints may be time-consuming	⚠️ Medium
AI Understanding	AI models have limitations in understanding UE graph structures and pin types	⚠️ Caution

6.2 Unsupported Scenarios

C++ Code Operations: Can only operate on Blueprints and assets; cannot create or modify C++ code files
Runtime Debugging: Does not support debugging features such as breakpoints or step execution
Multi-User Collaboration: No concurrency control mechanism; not suitable for multiple users operating the same Blueprint simultaneously
Content Migration: Cross-project content migration is not supported
Source Control Integration: Does not directly interact with Perforce/Git/SVN
Packaging and Building: Does not support packaging, baking, or other build processes
Level Editing: Does not directly support Actor placement and editing in levels
Data Table Operations: Editing of DataTable/CurveTable is not currently supported
Niagara System: Operations on Niagara particle systems are not supported
UI/UW Editing: Editing of Widget Blueprints is not supported

6.3 Security Boundaries

✅ Allowed:
   · Read/Create/Modify Blueprint assets
   · Read/Create/Modify Material assets
   · Read/Create/Modify Anim Blueprint assets
   · Create structs and enums
   · Perform safe snapshots and restoration
   · Use Ctrl+Z to undo in the editor

❌ Not Allowed:
   · Expose the editor to external network access
   · Batch modifications without version control
   · Relying on AI to fully understand the semantics of complex graph structures
   · Skipping tests and using directly on critical nodes

⚠️ Proceed with Caution:
   · Modifying the parent class of an existing Blueprint (may cause numerous broken connections)
   · Batch renaming/deleting assets
   · Changing variable types (may disconnect existing connections)
   · Large-scale modifications in Anim Blueprint state machines

7. Challenges in Prompt Accuracy for Dialogue-Based MCP Operations

7.1 Core Challenges

Using natural language to operate UE5 Blueprints through AI models presents the following core challenges:

Challenge 1: Loss of 3D Semantics in Graph Structure

A Blueprint graph is a two-dimensional visual structure. AI only sees a flat JSON node list, losing spatial information such as:

Node position and layout (proximity implies logical grouping)
Visual grouping through comment boxes
Execution flow direction (left-to-right, top-to-bottom conventions)
Color cues (node type indication, execution wire colors)

Impact: AI struggles to understand the "design intent" of a graph, only seeing structured connection data.

Challenge 2: Tacit Knowledge of Pin Types

Pin types in UE5 are a complex system:

Explicit Pin Information	Required Tacit Knowledge
PinCategory = "object"	Need to know the subclass inheritance tree
PinSubCategoryObject	Need to understand object reference vs. class reference
bIsReference	Need to know value vs. reference semantic differences
PinValueType	Need to understand key-value type relationships for Map/Set containers

Impact: When constructing connect_pins requests, AI may provide semantically incorrect pin pairings.

Challenge 3: Cascading Effects of Changes

A simple modification can trigger a chain reaction:

Change variable type (int → float)
  → Output pin types of all Get/Set nodes change
    → Nodes connected to these pins may become disconnected
      → Input values of downstream nodes become invalid
        → Compilation warnings or errors occur

Impact: AI struggles to fully predict all cascading effects of a change, even with dryRun support.

Challenge 4: Ambiguity of UE Terminology

Term	Meaning in Different Contexts
"Node"	Can be a Blueprint node, material expression, animation state, or skeleton node
"Connection"	Can be a pin connection, state transition, or component parent-child relationship
"Type"	Can be a variable type, pin type, node type, or asset type
"Graph"	Can be EventGraph, FunctionGraph, AnimationGraph, or MaterialGraph

Impact: AI may confuse terminology meanings across different contexts, leading to incorrect request parameters.

Challenge 5: Session State Maintenance

Round 1: AI → "List all Blueprints"
         Service → Returns 50 Blueprint names

Round 2: AI → "Open the first one"
         Problem → Which "first one"? The user needs to maintain dialog context

Impact: The plugin itself is stateless; each tool call is independent. AI models need to maintain state within the conversation, but context windows are limited.

7.2 Current Mitigation Strategies

Mitigation measures already implemented at the plugin level:

Detailed Error Messages: When an operation fails, return specific error reasons and a list of available options (such as available pin names, available graph names, etc.)
dryRun Mode: Key modification operations support a preview mode that returns impact analysis
Snapshot Mechanism: Supports taking snapshots before operations and restoring after
SEH Protection: Crash protection for extreme cases

10. FAQ and Troubleshooting

10.1 Operation Issues

Q: Changes to Blueprint did not take effect

Check whether the saved field in the returned JSON is true
Manually save the asset in the editor (Ctrl+S)
Reopen the Blueprint graph to view changes

Q: Blueprint compilation error

Use the validate_blueprint tool to view specific error details
If a snapshot is available, use restore_graph to restore
Or use Ctrl+Z in the editor to undo

Q: AI cannot find the specified Blueprint

Ensure the Blueprint name is correct (case-sensitive)
Use the list_blueprints tool to view all available Blueprints
Level Blueprint needs to be referenced by map name

10.2 Performance Issues

Q: First list_blueprints call is slow

The first call triggers a full scan of the asset registry. Subsequent calls use the cache and will be faster.

11. Appendix: Capability Statistics

11.1 Overview Data

Stat Item	Value
MCP Tools Total	80+
Capability Domains	9 Major Categories
Supported Asset Types	Blueprint, Material, MaterialInstance, MaterialFunction, AnimBlueprint, UserDefinedStruct, UserDefinedEnum, BlendSpace

11.3 Type Support Coverage

Blueprint Pin Type	Support Status
boolean, byte, int, int64, float, double, name, string, text	✅ Full
object, softobject, class, softclass, interface	✅ Full
struct (Vector, Transform, Rotator, Color, etc.)	✅ Full
enum	✅ Full
array, set, map	✅ Basic Support
delegate, mcdelegate	✅ Basic Support

Conclusion

UECopilot's goal is to make AI a trusted co-pilot for UE5 developers — not to replace your judgment, but to help you complete repetitive tasks faster, reduce human error, and maintain accuracy and traceability in large-scale projects.

Recommendations for Users:

Start small: Try it on simple Blueprints first
Use snapshots: Take a snapshot before any major operation
Gradual usage: Progress from reading → simple modifications → complex creation
Provide feedback: When encountering issues, please provide detailed logs to help the plugin improve continuously

UECopilot - Empowering Unreal Engine development with AI wings

UECopilot Plugin Documentation

Version: 1.0.0 | Last Updated: 2026-05-08 Target Engine: Unreal Engine 5.7

1. Plugin Overview

1.1 What is UECopilot?

One-sentence summary: UECopilot enables AI to "understand" your Blueprints and operate them for you like an experienced TA/programmer.

1.2 Operation Mode

Mode	Startup Method	Use Case	Features
Editor Mode	Automatically loaded when UE5 editor starts	Daily development	Editor and MCP service coexist, real-time operation

2. Core Capabilities Overview

UECopilot's UEMCP module has been comprehensively analyzed and currently provides 80+ MCP tools, covering the following 9 major capability domains:

Capability Domain	Tool Count	Capability Rating
Blueprint Reading & Retrieval	8	Stable
Blueprint Graph Editing & Node Operations	15	Stable
Blueprint Variables & Type System	6	Stable
Function/Parameter Management	4	Stable
Blueprint Structure & Metadata	9	Stable
Material System	18	Mature
Animation Blueprint System	12	Developing
Safety & Snapshot System	6	Stable
Asset Discovery & Reflection	5	Mature
Unreal Python API (AI + World Building)	Level Automation (Procedural Tools)	Planned

Capability Rating Descriptions:

Mature: Full tool functionality, edge cases well handled, SEH protection in place

Stable: Core paths usable, some boundary conditions to watch for

Developing: Basic capabilities available, advanced scenarios need improvement

2.1 What Can It Do? (Scenario Descriptions)

Scenario 1: AI-Assisted Blueprint Debugging

User: "Help me check if there are any disconnected pins in this Blueprint"
AI → calls find_disconnected_pins → returns all unconnected input pins
AI → provides fix suggestions

Scenario 2: AI-Assisted Blueprint Refactoring

User: "Change all function calls referencing OldClass to NewClass"
AI → calls replace_function_calls (supports dry_run preview) → executes replacement

Scenario 3: AI-Assisted Material Creation

User: "Help me create a material with a normal map and color adjustment"
AI → create_material → add_material_expression (TextureSample, Multiply, etc.)
     → connect_material_pins → completes the material network

Scenario 4: AI-Assisted Animation State Machine

User: "Add an Idle→Run transition in this Anim Blueprint"
AI → add_anim_state → add_anim_transition → set_transition_rule

Scenario 5: Safe Experimentation

User: "I want to modify this function parameter type, but I'm worried about issues"
AI → snapshot_graph (take snapshot first) → change_function_parameter_type → if error, restore_graph

3. System Requirements

Unreal Engine: 5.7+
Operating System: Windows 64-bit (fully tested)
Additional Dependencies: Node.js (for Web UI service, MCP service does not require it)

4. Usage Guide

4.1 Recommended Workflow

The recommended workflow follows four steps: "Preview → Snapshot → Execute → Verify":

Step 1: Preview & Analysis
  ├── Use get_blueprint / get_blueprint_graph to understand current state
  ├── Use search_blueprints to search for relevant nodes
  └── Use check_pin_compatibility to pre-check pin connection feasibility

Step 2: Create Safety Snapshot
  └── Use snapshot_graph to save the current graph state

Step 3: Execute Changes
  ├── Use add_node / connect_pins / delete_node, etc.
  ├── Tools with dryRun parameter should be used for a dry run first
  └── For major changes, use validate_blueprint to check compilation results

Step 4: Verify & Restore
  ├── Use validate_blueprint to verify Blueprint integrity
  ├── Use diff_graph to compare differences before and after changes
  └── If issues arise, use restore_graph to roll back to the snapshot state

4.2 AI Prompt Tips

Good prompt examples:

# Clearly specify the target object
"Add a Print String node to the EventGraph of Blueprint MyCharacter, printing 'Hello'"

# Step-by-step operations
"1. First take a snapshot of MyCharacter's EventGraph
 2. Then change the input parameter type of the MoveForward function from float to double
 3. Finally verify if the Blueprint has compilation errors"

# Query first, then operate
"First list all Blueprints in the project that inherit from Character,
 then tell me their names and paths"

Vague prompts to avoid:

✗ "Help me fix this Blueprint" — Which Blueprint? Fix what?
✗ "Add a feature" — What feature? Where to add it?
✗ "Modify the material" — Which material? Change it to what?

4.3 Usage Notes

MCP service is not head-safe: Although SEH (Structured Exception Handling) protection is used, erroneous operations in extreme cases could still cause the editor to crash. It is recommended to save the project and back up important Blueprints before operating.
All write operations support Ctrl+Z undo: The server wraps each write operation in an Undo transaction, but it is recommended to manually save promptly after continuous operations.
Snapshots are saved to disk: Snapshot files are stored in the Project/Saved/BlueprintMCP/Snapshots/ directory and are not included in project version control. Manual backup is recommended for important operations.
AI model differences in understanding UE terminology: Different AI models may have varying understandings of UE-specific terms (such as "pin connection", "break struct", "event dispatcher"). Please use UE5 official terminology in your prompts.

5. MCP Tools Complete Reference

Note: The following lists all MCP tools that can be directly invoked through AI conversation. Tool names use snake_case convention. You can use these tool names directly in your prompts.

5.1 Blueprint Retrieval & Reading (8 Tools)

Tool Name	Function	Key Parameters
`list_blueprints`	List all Blueprint assets, supports filtering by name and parent class	`filter`, `parentClass`, `type`
`get_blueprint`	Get detailed info of a specific Blueprint (variables, functions, components, etc.)	`name`
`get_blueprint_summary`	Get a brief summary of a Blueprint (same as get_blueprint)	`name`
`get_blueprint_graph`	Get the full structure of a specified graph (EventGraph, FunctionGraph, etc.)	`name`, `graph`
`describe_graph`	Get a pseudocode-style description of a graph (same as get_blueprint_graph)	`name`, `graph`
`search_blueprints`	Search for nodes with specific names in Blueprints	`query`, `path`, `maxResults`
`find_asset_references`	Find all nodes referencing a specified class	`class`, `blueprint`
`search_by_type`	Search for usage of a specific node type in Blueprints	`nodeClass`, `blueprint`, `graph`

5.2 Blueprint Node Editing (15 Tools)

Tool Name	Function	Key Parameters
`add_node`	Add a new node to a specified graph	`blueprint`, `graph`, `nodeType`, `position`
`delete_node`	Delete a node from a graph	`blueprint`, `nodeId`
`duplicate_nodes`	Duplicate one or more nodes	`blueprint`, `nodeIds`, `offset`
`move_node`	Move a node to a new position	`blueprint`, `nodeId`, `position`
`connect_pins`	Connect pins between two nodes	`blueprint`, `sourceNodeId`, `sourcePin`, `targetNodeId`, `targetPin`
`disconnect_pin`	Disconnect all connections of a specified pin	`blueprint`, `nodeId`, `pinName`
`refresh_all_nodes`	Refresh all nodes in a graph (clean up broken references)	`blueprint`
`set_pin_default`	Set the default value of a pin	`blueprint`, `nodeId`, `pinName`, `value`
`get_pin_info`	Get detailed pin info (type, direction, connection status)	`blueprint`, `nodeId`, `pinName`
`check_pin_compatibility`	Pre-check if two pins can be connected	`blueprint`, `sourceNodeId`, `sourcePin`, `targetNodeId`, `targetPin`
`get_node_comment`	Get a node's comment text	`blueprint`, `nodeId`
`set_node_comment`	Set a node's comment text	`blueprint`, `nodeId`, `comment`
`replace_function_calls`	Replace function call target class in Blueprints (supports dry_run preview)	`blueprint`, `oldClass`, `newClass`, `dryRun`
`change_struct_node_type`	Change the struct type of Break/Make struct nodes	`blueprint`, `nodeId`, `structType`

5.3 Blueprint Variable System (6 Tools)

Tool Name	Function	Key Parameters
`add_variable`	Add a new member variable to a Blueprint	`blueprint`, `variableName`, `variableType`, `category`
`remove_variable`	Remove a member variable from a Blueprint	`blueprint`, `variableName`
`change_variable_type`	Change a variable's type (supports dry_run impact analysis preview)	`blueprint`, `variable`, `newType`, `dryRun`
`set_variable_metadata`	Set a variable's metadata (category, description, etc.)	`blueprint`, `variable`, `metadata`
`set_blueprint_default`	Set a Blueprint CDO default property value	`blueprint`, `propertyName`, `value`
`delete_asset`	Delete a specified asset file	`path`

5.4 Function & Parameter Management (4 Tools)

Tool Name	Function	Key Parameters
`add_function_parameter`	Add a parameter to a function/custom event	`blueprint`, `functionName`, `paramName`, `paramType`
`remove_function_parameter`	Remove a parameter from a function/custom event	`blueprint`, `functionName`, `paramName`
`change_function_parameter_type`	Change a function parameter type (supports dry_run preview)	`blueprint`, `functionName`, `paramName`, `newType`, `dryRun`
`reparent_blueprint`	Change a Blueprint's parent class (supports C++ classes and Blueprint classes)	`blueprint`, `newParentClass`

5.5 Blueprint Structure & Metadata (9 Tools)

Tool Name	Function	Key Parameters
`create_blueprint`	Create a new Blueprint asset	`blueprintName`, `packagePath`, `parentClass`, `blueprintType`
`create_graph`	Create a new graph in a Blueprint (EventGraph, FunctionGraph, etc.)	`blueprint`, `graphName`, `graphType`
`delete_graph`	Delete a specified graph from a Blueprint	`blueprint`, `graphName`
`rename_graph`	Rename a graph in a Blueprint	`blueprint`, `oldName`, `newName`
`add_interface`	Add an interface implementation to a Blueprint	`blueprint`, `interfaceName`
`remove_interface`	Remove an interface implementation from a Blueprint (optionally keep functions)	`blueprint`, `interfaceName`, `preserveFunctions`
`list_interfaces`	List all interfaces implemented by a Blueprint	`blueprint`
`add_event_dispatcher`	Add an event dispatcher (supports dispatchers with parameters)	`blueprint`, `dispatcherName`, `parameters`
`list_event_dispatchers`	List all event dispatchers and their parameters for a Blueprint	`blueprint`

5.6 Component System (3 Tools)

Tool Name	Function	Key Parameters
`add_component`	Add a component to a Blueprint's SCS	`blueprint`, `componentClass`, `name`, `parentComponent`
`remove_component`	Remove a component from a Blueprint's SCS	`blueprint`, `componentName`
`list_components`	List all components in a Blueprint's SCS	`blueprint`

5.7 User-Defined Types (4 Tools)

Tool Name	Function	Key Parameters
`create_struct`	Create a user-defined struct asset (supports adding properties)	`assetPath`, `properties`
`create_enum`	Create a user-defined enum asset	`assetPath`, `values`
`add_struct_property`	Add a new property to a struct	`structPath`, `propertyName`, `propertyType`
`remove_struct_property`	Remove a property from a struct	`structPath`, `propertyName`

5.8 Material System (18 Tools)

Material Reading:

Tool Name	Function	Key Parameters
`list_materials`	List all material and material instance assets	`filter`, `type`
`get_material`	Get detailed material info (domain, blend mode, parameter list, referenced textures)	`name`
`get_material_graph`	Get the node connection structure of a material graph	`name`
`describe_material`	Provide a detailed pseudocode description of a material graph	`material`
`search_materials`	Search for expressions in materials	`query`
`find_material_references`	Find materials referencing a specified texture or material function	`texture`, `materialFunction`

Material Writing:

Tool Name	Function	Key Parameters
`create_material`	Create a new material asset (supports domain and blend mode settings)	`name`, `packagePath`, `domain`, `blendMode`
`set_material_property`	Set material top-level properties (domain, blend mode, two-sided, etc.)	`material`, `property`, `value`
`add_material_expression`	Add an expression node to a material graph	`material`, `expressionClass`, `position`
`delete_material_expression`	Delete an expression from a material graph	`material`, `expressionId`
`connect_material_pins`	Connect two pins in a material graph	`material`, `expression`, `pinName`, `targetExpression`, `targetPin`
`disconnect_material_pin`	Disconnect all connections of a specified material pin	`material`, `expressionId`, `pinName`
`set_expression_value`	Set a material expression's parameter value	`material`, `expressionId`, `parameter`, `value`
`move_material_expression`	Move a material expression's position in the editor graph	`material`, `expressionId`, `position`

Material Instances:

Tool Name	Function	Key Parameters
`create_material_instance`	Create a Material Instance Constant (MIC)	`name`, `packagePath`, `parentMaterial`
`set_material_instance_parameter`	Set a material instance's parameter override value	`materialInstance`, `parameterName`, `value`, `type`
`get_material_instance_parameters`	Get all overridable parameters of a material instance	`materialInstance`
`reparent_material_instance`	Change a material instance's parent material	`materialInstance`, `newParent`

Material Functions:

Tool Name	Function	Key Parameters
`list_material_functions`	List all material function assets	`filter`
`get_material_function`	Get detailed information about a material function	`name`
`create_material_function`	Create a new material function asset	`name`, `packagePath`

Material Safety:

Tool Name	Function	Key Parameters
`validate_material`	Compile and validate a material	`material`
`snapshot_material_graph`	Take a snapshot of a material graph	`material`
`diff_material_graph`	Compare differences between a material graph and its snapshot	`material`, `snapshotId`
`restore_material_graph`	Restore a material graph from a snapshot	`material`, `snapshotId`

5.9 Animation Blueprint System (12 Tools)

Tool Name	Function	Key Parameters
`create_anim_blueprint`	Create an Animation Blueprint asset	`name`, `packagePath`, `skeleton`, `parentClass`
`add_state_machine`	Add a state machine to an Anim Blueprint	`blueprint`, `name`
`add_anim_state`	Add an animation state to a state machine	`blueprint`, `stateMachine`, `stateName`
`remove_anim_state`	Remove an animation state from a state machine	`blueprint`, `stateName`
`add_anim_transition`	Add a transition rule between states	`blueprint`, `fromState`, `toState`
`set_transition_rule`	Set the rule Blueprint for a state transition	`blueprint`, `transitionId`, `ruleBlueprint`
`add_anim_node`	Add an animation node to an animation state	`blueprint`, `stateName`, `nodeType`
`set_state_animation`	Set the animation sequence used by a state	`blueprint`, `stateName`, `animation`
`list_anim_slots`	List an Anim Blueprint's slots	`blueprint`
`list_sync_groups`	List an Anim Blueprint's sync groups	`blueprint`
`create_blend_space`	Create a blend space asset (1D/2D)	`name`, `packagePath`, `skeleton`
`set_blend_space_samples`	Set the sample points of a blend space	`blendSpace`, `samples`

5.10 Safety & Snapshot System (6 Tools)

Tool Name	Function	Key Parameters
`snapshot_graph`	Create a Blueprint graph snapshot (saved to disk)	`blueprint`, `graphs`
`diff_graph`	Compare the current graph with a snapshot	`blueprint`, `snapshotId`
`restore_graph`	Restore a Blueprint graph from a snapshot	`blueprint`, `snapshotId`
`find_disconnected_pins`	Find all unconnected input pins in a graph	`blueprint`
`analyze_rebuild_impact`	Analyze the potential impact scope of a Blueprint rebuild	`blueprint`, `changeDescription`
`diff_blueprints`	Compare the graph structure differences between two Blueprints	`blueprintA`, `blueprintB`, `graph`

5.11 Asset Discovery & Reflection (5 Tools)

Tool Name	Function	Key Parameters
`list_classes`	List all available UClasses	`filter`
`list_functions`	List all functions of a specified class	`className`, `filter`
`list_properties`	List all properties of a specified class	`className`, `filter`
`rescan_assets`	Rescan the asset registry, refresh cache	None
`server_status`	View MCP server runtime status and asset statistics	None

5.12 Utility Functions & Safety Mechanisms

Type Resolver (ResolveTypeFromString)

Supported type resolution formats:

Input Format	Example	Resolution Result
Basic Types	`int`, `float`, `bool`, `string`, `text`	Corresponding basic pin types
Object Reference	`object:Actor`	UObject subclass reference
Soft Object	`softobject:Texture2D`	Soft object reference
Class Reference	`class:Actor`	Class reference
Soft Class Reference	`softclass:AnimInstance`	Soft class reference
Struct	`struct:Vector`, `struct:Transform`	Struct pin type
Enum	`enum:ETraceTypeQuery`	Enum byte type
Interface	`interface:BPI_Interact`	Interface reference
Array	`array:int`, `array:object:Actor`	TArray type

SEH Safety Protection (Windows Only)

Undo Transaction Support

All tool calls that modify Blueprints are wrapped in Undo/Redo transactions. This means that when used in the editor, operations executed by AI can be undone with Ctrl+Z.

6. Usage Boundaries & Limitations

6.1 Known Limitations

Category	Description	Impact
Multi-User	The service is designed for single-user; simultaneous multi-user operations are not supported	⚠️ Medium
Network	Only listens on 127.0.0.1, remote access not supported	🔒 Security Design
Version Compatibility	Based on UE5.4+ API, not tested on UE4	⚠️ High
Platform	SEH protection is Windows-only; material system SEH has a dedicated implementation	⚠️ Medium
Hot Reload	Plugin module needs to reconnect after hot reload	⚠️ Low
Large Projects	Ultra-large projects with tens of thousands of Blueprints may take a few seconds for the initial scan	⚠️ Medium
Compilation Safety	Blueprint compilation triggers the full compilation chain; complex Blueprints may be time-consuming	⚠️ Medium
AI Understanding	AI models have limitations in understanding UE graph structures and pin types	⚠️ Caution

6.2 Unsupported Scenarios

C++ Code Operations: Can only operate on Blueprints and assets; cannot create or modify C++ code files
Runtime Debugging: Does not support debugging features such as breakpoints or step execution
Multi-User Collaboration: No concurrency control mechanism; not suitable for multiple users operating the same Blueprint simultaneously
Content Migration: Cross-project content migration is not supported
Source Control Integration: Does not directly interact with Perforce/Git/SVN
Packaging and Building: Does not support packaging, baking, or other build processes
Level Editing: Does not directly support Actor placement and editing in levels
Data Table Operations: Editing of DataTable/CurveTable is not currently supported
Niagara System: Operations on Niagara particle systems are not supported
UI/UW Editing: Editing of Widget Blueprints is not supported

6.3 Security Boundaries

✅ Allowed:
   · Read/Create/Modify Blueprint assets
   · Read/Create/Modify Material assets
   · Read/Create/Modify Anim Blueprint assets
   · Create structs and enums
   · Perform safe snapshots and restoration
   · Use Ctrl+Z to undo in the editor

❌ Not Allowed:
   · Expose the editor to external network access
   · Batch modifications without version control
   · Relying on AI to fully understand the semantics of complex graph structures
   · Skipping tests and using directly on critical nodes

⚠️ Proceed with Caution:
   · Modifying the parent class of an existing Blueprint (may cause numerous broken connections)
   · Batch renaming/deleting assets
   · Changing variable types (may disconnect existing connections)
   · Large-scale modifications in Anim Blueprint state machines

7. Challenges in Prompt Accuracy for Dialogue-Based MCP Operations

7.1 Core Challenges

Using natural language to operate UE5 Blueprints through AI models presents the following core challenges:

Challenge 1: Loss of 3D Semantics in Graph Structure

A Blueprint graph is a two-dimensional visual structure. AI only sees a flat JSON node list, losing spatial information such as:

Node position and layout (proximity implies logical grouping)
Visual grouping through comment boxes
Execution flow direction (left-to-right, top-to-bottom conventions)
Color cues (node type indication, execution wire colors)

Impact: AI struggles to understand the "design intent" of a graph, only seeing structured connection data.

Challenge 2: Tacit Knowledge of Pin Types

Pin types in UE5 are a complex system:

Explicit Pin Information	Required Tacit Knowledge
PinCategory = "object"	Need to know the subclass inheritance tree
PinSubCategoryObject	Need to understand object reference vs. class reference
bIsReference	Need to know value vs. reference semantic differences
PinValueType	Need to understand key-value type relationships for Map/Set containers

Impact: When constructing connect_pins requests, AI may provide semantically incorrect pin pairings.

Challenge 3: Cascading Effects of Changes

A simple modification can trigger a chain reaction:

Change variable type (int → float)
  → Output pin types of all Get/Set nodes change
    → Nodes connected to these pins may become disconnected
      → Input values of downstream nodes become invalid
        → Compilation warnings or errors occur

Impact: AI struggles to fully predict all cascading effects of a change, even with dryRun support.

Challenge 4: Ambiguity of UE Terminology

Term	Meaning in Different Contexts
"Node"	Can be a Blueprint node, material expression, animation state, or skeleton node
"Connection"	Can be a pin connection, state transition, or component parent-child relationship
"Type"	Can be a variable type, pin type, node type, or asset type
"Graph"	Can be EventGraph, FunctionGraph, AnimationGraph, or MaterialGraph

Impact: AI may confuse terminology meanings across different contexts, leading to incorrect request parameters.

Challenge 5: Session State Maintenance

Round 1: AI → "List all Blueprints"
         Service → Returns 50 Blueprint names

Round 2: AI → "Open the first one"
         Problem → Which "first one"? The user needs to maintain dialog context

Impact: The plugin itself is stateless; each tool call is independent. AI models need to maintain state within the conversation, but context windows are limited.

7.2 Current Mitigation Strategies

Mitigation measures already implemented at the plugin level:

Detailed Error Messages: When an operation fails, return specific error reasons and a list of available options (such as available pin names, available graph names, etc.)
dryRun Mode: Key modification operations support a preview mode that returns impact analysis
Snapshot Mechanism: Supports taking snapshots before operations and restoring after
SEH Protection: Crash protection for extreme cases

10. FAQ and Troubleshooting

10.1 Operation Issues

Q: Changes to Blueprint did not take effect

Check whether the saved field in the returned JSON is true
Manually save the asset in the editor (Ctrl+S)
Reopen the Blueprint graph to view changes

Q: Blueprint compilation error

Use the validate_blueprint tool to view specific error details
If a snapshot is available, use restore_graph to restore
Or use Ctrl+Z in the editor to undo

Q: AI cannot find the specified Blueprint

Ensure the Blueprint name is correct (case-sensitive)
Use the list_blueprints tool to view all available Blueprints
Level Blueprint needs to be referenced by map name

10.2 Performance Issues

Q: First list_blueprints call is slow

The first call triggers a full scan of the asset registry. Subsequent calls use the cache and will be faster.

11. Appendix: Capability Statistics

11.1 Overview Data

Stat Item	Value
MCP Tools Total	80+
Capability Domains	9 Major Categories
Supported Asset Types	Blueprint, Material, MaterialInstance, MaterialFunction, AnimBlueprint, UserDefinedStruct, UserDefinedEnum, BlendSpace

11.3 Type Support Coverage

Blueprint Pin Type	Support Status
boolean, byte, int, int64, float, double, name, string, text	✅ Full
object, softobject, class, softclass, interface	✅ Full
struct (Vector, Transform, Rotator, Color, etc.)	✅ Full
enum	✅ Full
array, set, map	✅ Basic Support
delegate, mcdelegate	✅ Basic Support

Conclusion

Recommendations for Users:

Start small: Try it on simple Blueprints first
Use snapshots: Take a snapshot before any major operation
Gradual usage: Progress from reading → simple modifications → complex creation
Provide feedback: When encountering issues, please provide detailed logs to help the plugin improve continuously

UECopilot - Empowering Unreal Engine development with AI wings

#UECopilot Plugin Documentation

#1. Plugin Overview

#1.1 What is UECopilot?

#1.2 Operation Mode

#2. Core Capabilities Overview

#2.1 What Can It Do? (Scenario Descriptions)

#3. System Requirements

#4. Usage Guide

#4.1 Recommended Workflow

#4.2 AI Prompt Tips

#4.3 Usage Notes

#5. MCP Tools Complete Reference

#5.1 Blueprint Retrieval & Reading (8 Tools)

#5.2 Blueprint Node Editing (15 Tools)

#5.3 Blueprint Variable System (6 Tools)

#5.4 Function & Parameter Management (4 Tools)

#5.5 Blueprint Structure & Metadata (9 Tools)

#5.6 Component System (3 Tools)

#5.7 User-Defined Types (4 Tools)

#5.8 Material System (18 Tools)

#5.9 Animation Blueprint System (12 Tools)

#5.10 Safety & Snapshot System (6 Tools)

#5.11 Asset Discovery & Reflection (5 Tools)

#5.12 Utility Functions & Safety Mechanisms

#6. Usage Boundaries & Limitations

#6.1 Known Limitations

#6.2 Unsupported Scenarios

#6.3 Security Boundaries

#7. Challenges in Prompt Accuracy for Dialogue-Based MCP Operations

#7.1 Core Challenges

#Challenge 1: Loss of 3D Semantics in Graph Structure

#Challenge 2: Tacit Knowledge of Pin Types

#Challenge 3: Cascading Effects of Changes

#Challenge 4: Ambiguity of UE Terminology

#Challenge 5: Session State Maintenance

#7.2 Current Mitigation Strategies

#10. FAQ and Troubleshooting

#10.1 Operation Issues

#10.2 Performance Issues

#The first call triggers a full scan of the asset registry. Subsequent calls use the cache and will be faster.

#11. Appendix: Capability Statistics

#11.1 Overview Data

#11.3 Type Support Coverage

#Conclusion

#UECopilot Plugin Documentation

#1. Plugin Overview

#1.1 What is UECopilot?

#1.2 Operation Mode

#2. Core Capabilities Overview

#2.1 What Can It Do? (Scenario Descriptions)

#3. System Requirements

#4. Usage Guide

#4.1 Recommended Workflow

#4.2 AI Prompt Tips

#4.3 Usage Notes

#5. MCP Tools Complete Reference

#5.1 Blueprint Retrieval & Reading (8 Tools)

#5.2 Blueprint Node Editing (15 Tools)

#5.3 Blueprint Variable System (6 Tools)

#5.4 Function & Parameter Management (4 Tools)

#5.5 Blueprint Structure & Metadata (9 Tools)

#5.6 Component System (3 Tools)

#5.7 User-Defined Types (4 Tools)

#5.8 Material System (18 Tools)

#5.9 Animation Blueprint System (12 Tools)

#5.10 Safety & Snapshot System (6 Tools)

#5.11 Asset Discovery & Reflection (5 Tools)

#5.12 Utility Functions & Safety Mechanisms

#6. Usage Boundaries & Limitations

#6.1 Known Limitations

#6.2 Unsupported Scenarios

#6.3 Security Boundaries

#7. Challenges in Prompt Accuracy for Dialogue-Based MCP Operations

#7.1 Core Challenges

#Challenge 1: Loss of 3D Semantics in Graph Structure

#Challenge 2: Tacit Knowledge of Pin Types

#Challenge 3: Cascading Effects of Changes

#Challenge 4: Ambiguity of UE Terminology

#Challenge 5: Session State Maintenance

#7.2 Current Mitigation Strategies

UECopilot Plugin Documentation

1. Plugin Overview

1.1 What is UECopilot?

1.2 Operation Mode

2. Core Capabilities Overview

2.1 What Can It Do? (Scenario Descriptions)

3. System Requirements

4. Usage Guide

4.1 Recommended Workflow

4.2 AI Prompt Tips

4.3 Usage Notes

5. MCP Tools Complete Reference

5.1 Blueprint Retrieval & Reading (8 Tools)

5.2 Blueprint Node Editing (15 Tools)

5.3 Blueprint Variable System (6 Tools)

5.4 Function & Parameter Management (4 Tools)

5.5 Blueprint Structure & Metadata (9 Tools)

5.6 Component System (3 Tools)

5.7 User-Defined Types (4 Tools)

5.8 Material System (18 Tools)

5.9 Animation Blueprint System (12 Tools)

5.10 Safety & Snapshot System (6 Tools)

5.11 Asset Discovery & Reflection (5 Tools)

5.12 Utility Functions & Safety Mechanisms

6. Usage Boundaries & Limitations

6.1 Known Limitations

6.2 Unsupported Scenarios

6.3 Security Boundaries

7. Challenges in Prompt Accuracy for Dialogue-Based MCP Operations

7.1 Core Challenges

Challenge 1: Loss of 3D Semantics in Graph Structure

Challenge 2: Tacit Knowledge of Pin Types

Challenge 3: Cascading Effects of Changes

Challenge 4: Ambiguity of UE Terminology

Challenge 5: Session State Maintenance

7.2 Current Mitigation Strategies

10. FAQ and Troubleshooting

10.1 Operation Issues

10.2 Performance Issues

The first call triggers a full scan of the asset registry. Subsequent calls use the cache and will be faster.

11. Appendix: Capability Statistics

11.1 Overview Data

11.3 Type Support Coverage

Conclusion

UECopilot Plugin Documentation

1. Plugin Overview

1.1 What is UECopilot?

1.2 Operation Mode

2. Core Capabilities Overview

2.1 What Can It Do? (Scenario Descriptions)

3. System Requirements

4. Usage Guide

4.1 Recommended Workflow

4.2 AI Prompt Tips

4.3 Usage Notes

5. MCP Tools Complete Reference

5.1 Blueprint Retrieval & Reading (8 Tools)

5.2 Blueprint Node Editing (15 Tools)

5.3 Blueprint Variable System (6 Tools)

5.4 Function & Parameter Management (4 Tools)

5.5 Blueprint Structure & Metadata (9 Tools)

5.6 Component System (3 Tools)

5.7 User-Defined Types (4 Tools)

5.8 Material System (18 Tools)

5.9 Animation Blueprint System (12 Tools)

5.10 Safety & Snapshot System (6 Tools)

5.11 Asset Discovery & Reflection (5 Tools)

5.12 Utility Functions & Safety Mechanisms

6. Usage Boundaries & Limitations

6.1 Known Limitations

6.2 Unsupported Scenarios

6.3 Security Boundaries

7. Challenges in Prompt Accuracy for Dialogue-Based MCP Operations

7.1 Core Challenges

Challenge 1: Loss of 3D Semantics in Graph Structure

Challenge 2: Tacit Knowledge of Pin Types

Challenge 3: Cascading Effects of Changes

Challenge 4: Ambiguity of UE Terminology

Challenge 5: Session State Maintenance

7.2 Current Mitigation Strategies