UE5 Editor Control

HTTP API for the UE5 editor. Plugin UE5AIAssistant runs on localhost:58080.

Auto-Setup Flow (MUST follow on first use)

Every time you need to use this skill, start here:

Step 1: Check if plugin is already running

curl -s --max-time 3 http://localhost:58080/api/ping

• If response contains "success": true → Skip to Quick Start below
• If connection refused / timeout → Plugin not running, continue to Step 2

Step 2: Find user's UE5 project

Ask the user: "你的 UE5 项目路径是什么？"

Or auto-detect (look for .uproject files):

# macOS common locations
find ~/Documents ~/Desktop ~/Projects ~/codeprojects -maxdepth 3 -name "*.uproject" 2>/dev/null

Save the project path for later use.

Step 3: Check if plugin is installed in the project

# Check if plugin exists in the UE5 project
test -f "<UE5_PROJECT_PATH>/Plugins/UE5AIAssistant/UE5AIAssistant.uplugin" && echo "INSTALLED" || echo "NOT INSTALLED"

• If INSTALLED → Tell user: "插件已安装，请打开 UE5 编辑器然后告诉我"
• If NOT INSTALLED → Continue to Step 4

Step 4: Install the plugin

Option A — Download prebuilt binary (recommended, no C++ required):

bash scripts/install.sh "<UE5_PROJECT_PATH>"

If this fails (no releases published yet), fall back to Option B.

Option B — Copy source code (requires UE5 C++ compilation):

The skill's GitHub repo contains the C++ source. Clone and copy:

# Clone the repo (if not already available)
git clone https://github.com/1103837067/ue5-editor-control.git /tmp/ue5-editor-control

# Copy plugin source to UE5 project
mkdir -p "<UE5_PROJECT_PATH>/Plugins/UE5AIAssistant"
cp -r /tmp/ue5-editor-control/Source "<UE5_PROJECT_PATH>/Plugins/UE5AIAssistant/"
cp /tmp/ue5-editor-control/UE5AIAssistant.uplugin "<UE5_PROJECT_PATH>/Plugins/UE5AIAssistant/"

Then tell user: "插件已复制到项目中。请打开 UE5 编辑器，它会自动编译插件。打开后告诉我。"

Step 5: Verify connection

curl -s --max-time 3 http://localhost:58080/api/ping

If still failing, tell user to check:

• UE5 editor is open with the correct project
• Check Output Log for "UE5AIAssistant: HTTP server started on port 58080"
• Plugin is enabled: Edit → Plugins → search "UE5AIAssistant"

Prerequisites Summary

Requirement	Detail
UE5	5.4+ installed and project created
OS	macOS / Windows / Linux
curl	Pre-installed on macOS/Linux; Git Bash on Windows
UE5 Editor	Must be running with plugin enabled
C++ (Option B only)	Only if no prebuilt binary available for your platform

Quick Start

# Execute command (preferred for complex JSON)
curl -s -X POST -H "Content-Type: application/json" \
  -d '{"command":"get_actors_in_level","args":{}}' \
  http://localhost:58080/api/execute

# Simple commands via helper
bash scripts/ue5cmd.sh exec get_actors_in_level '{}'

Response: { "success": true|false, "data": {...}|null, "error": "..."|null }

Common Mistakes — Do NOT

• Do NOT add nodes one-by-one — always use batch_execute
• Do NOT guess C++ function names — use list_functions first
• Do NOT hardcode pin names — read them from response pins array
• Do NOT skip compile_blueprint after editing
• Do NOT use ue5cmd.sh for complex JSON — use curl directly

Task Router — Read the Right Module

Based on the user's task, read only the relevant module file for detailed commands, parameters, and workflows:

User wants to...	Read this file
Work with actors (spawn, delete, transform, properties)	references/actor.md
Build blueprint structure & logic (create BP, variables, functions, nodes, batch_execute)	references/blueprint.md
Create materials (expressions, connections, apply)	references/material.md
Build animation blueprints (state machines, states, transitions)	references/animation.md
Access any property via reflection, manage assets (create/read/write)	references/property.md
Set up Enhanced Input, configure character movement, build end-to-end characters	references/input-character.md

Rules:

1. Read only the module(s) needed for the current task — do NOT read all files
2. If unsure which module, check the table above or read the user's intent
3. Multiple tasks may require multiple modules (e.g., character = blueprint + input-character)

65 Commands Overview (for quick orientation only)

Category	Commands	Count
Actor	get_actors_in_level, find_actors_by_name, get_selected_actors, spawn_actor, delete_actor, set_actor_transform, get_actor_properties, set_actor_property, attach_actor, detach_actor	10
Blueprint Structure	create_blueprint, compile_blueprint, read_blueprint_content, create_variable, add_component_to_blueprint, create_function, add_function_parameter, create_event_dispatcher, create_blueprint_interface, implement_interface, add_widget_child	11
Blueprint Discovery	list_node_types, list_blueprint_classes, list_functions	3
Blueprint Nodes	add_node, connect_nodes, remove_node, get_node_pins, set_pin_default, batch_execute, add_pin, auto_layout_graph	8
Material	create_material, add_material_expression, connect_material_expressions, apply_material_to_actor, get_available_materials	5
Asset	search_assets, get_assets_by_class, get_asset_details	3
Editor	focus_viewport, get_current_level_info, save_all, get_project_settings, set_project_setting, get_world_settings, set_world_setting	7
Animation	create_anim_blueprint, get_anim_blueprint_info, add_anim_state_machine, add_anim_state, add_anim_transition, set_anim_state_animation, compile_anim_blueprint	7
Generic Reflection	list_components, list_properties, get_component_property, set_component_property, create_asset, get_asset_property, set_asset_property, call_function, get_object, modify_array_property, execute_python	11

Error Quick Reference

Error pattern	Fix
"not found"	Use discovery commands (find_actors_by_name, search_assets, list_functions, list_node_types, list_properties)
"Pin 'xxx' not found"	Error response lists all available pins — use the correct name
compile_blueprint diagnostics	Read references/blueprint.md error handling section