MCP 服务器

playcaller

An MCP server that enables AI agents to play-test Unity games by capturing screenshots and simulating inputs like taps, drags, and key presses, acting as a Playwright for Unity.

README

Playcaller

日本語はこちら

An MCP server that lets AI agents play-test Unity games like a real player. It provides screenshot capture, input simulation (tap, drag, flick, key press), Play Mode control, and more — all accessible from AI agents.

In short, it's a Playwright MCP for Unity.

Features

Game View screenshot capture
Tap, drag, flick, and key input simulation
Play Mode start / stop / pause
Scene GameObject hierarchy inspection
Console log retrieval
AssetDatabase refresh
Menu item execution
Editor state retrieval

Limitations

Not suited for testing fast-paced action games
Not suited for evaluating overall game experience
Not suited for judging visual effects quality

Requirements

Unity 2022.3 or later
Python 3.10 or later (uv recommended)

Setup

1. Install the Unity package

Open Window > Package Manager in the Unity Editor menu bar
Click the + button in the top-left corner
Select Add package from git URL...
Enter the following URL and click Add

https://github.com/takashicompany/playcaller.git

Newtonsoft.Json (com.unity.nuget.newtonsoft-json) will be installed automatically if not already present.

2. Register the MCP server

Run the following command:

claude mcp add playcaller -- uvx playcaller

If something doesn't work, try asking the AI for help.

3. Verify the connection

Launch Claude Code while the Unity Editor is open, and it will connect automatically.

Updating

Unity package

Open Window > Package Manager
Select Playcaller from the list
Click Update

MCP server (PyPI)

uvx --upgrade playcaller

and restart Claude Code.

Notes

Run In Background

If the game does not progress after starting Play Mode via MCP, the project's "Run In Background" setting may be disabled. Enable it in Edit > Project Settings > Player > Resolution and Presentation > Run In Background, or set Application.runInBackground = true in your game code.

HDR projects

In URP/HDRP projects with HDR enabled, playcaller_screenshot may hang due to a known Unity issue. Use playcaller_read_gameview_pixels instead, which reads the GameView's internal buffer directly and works with HDR.

MCP Tools

Tool	Description
`playcaller_screenshot`	Capture a Game View screenshot
`playcaller_read_gameview_pixels`	Capture Game View by reading internal buffer (HDR compatible)
`playcaller_tap`	Tap at specified coordinates
`playcaller_multi_tap`	Execute multiple taps in sequence
`playcaller_drag`	Drag operation
`playcaller_flick`	Flick (quick swipe) operation
`playcaller_key_press`	Keyboard input
`playcaller_playmode`	Start / stop / pause Play Mode
`playcaller_wait`	Wait for a specified time or frame count
`playcaller_console_log`	Retrieve Unity console logs
`playcaller_refresh`	Refresh AssetDatabase
`playcaller_get_hierarchy`	Get the GameObject hierarchy in the scene
`playcaller_get_gameobject`	Get detailed info about a specific GameObject
`playcaller_execute_menu_item`	Execute a Unity Editor menu item
`playcaller_get_editor_state`	Get the current editor state
`playcaller_game_query`	Send a custom query to the running game
`playcaller_set_game_view_size`	Set the Game View resolution