assets-find-built-in

Search Unity Editor's built-in assets like Materials and Shaders from the Resources/unity_builtin_extra folder to locate default resources for your projects.

Instructions

Search the built-in assets of the Unity Editor located in the built-in resources: Resources/unity_builtin_extra. Doesn't support GUIDs since built-in assets do not have them.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`name`	No	The name of the asset to filter by.
`type`	No	The type of the asset to filter by. Schema: "Material" or "Shader" or "Texture2D" etc. (Unity asset type name)
`maxResults`	No	Maximum number of assets to return. If the number of found assets exceeds this limit, the result will be truncated.	10

Implementation Reference

.claude/skills/unity-bridge/mcp_server.py:178-225 (handler)

The `call_tool` function in `mcp_server.py` handles the execution of MCP tools (including "assets-find-built-in") by writing commands to a filesystem-based IPC mechanism that the Unity Editor monitors.

def call_tool(name, arguments):
    """Execute a Unity Bridge tool via file IPC. Returns MCP content result."""
    bridge_dir = get_bridge_dir()
    commands_dir = os.path.join(bridge_dir, "commands")
    results_dir = os.path.join(bridge_dir, "results")

    # Heartbeat check
    err = check_heartbeat(bridge_dir)
    if err:
        return True, err

    # Write command
    command_id = f"{int(time.time())}-{uuid.uuid4().hex[:8]}"
    command = {"id": command_id, "tool": name, "params": arguments or {}}

    os.makedirs(commands_dir, exist_ok=True)
    os.makedirs(results_dir, exist_ok=True)

    command_file = os.path.join(commands_dir, f"{command_id}.json")
    write_atomic(command_file, json.dumps(command))

    # Poll for result
    result_file = os.path.join(results_dir, f"{command_id}.json")
    elapsed = 0.0

    while not os.path.exists(result_file):
        time.sleep(IPC_POLL_INTERVAL)
        elapsed += IPC_POLL_INTERVAL
        if elapsed >= IPC_TIMEOUT:
            try:
                os.remove(command_file)
            except OSError:
                pass
            return True, f"Timeout after {IPC_TIMEOUT}s waiting for Unity (tool: {name})"

    # Read result
    try:
        with open(result_file, "r", encoding="utf-8") as f:
            result = json.load(f)
    finally:
        try:
            os.remove(result_file)
        except OSError:
            pass

    is_error = result.get("status") != "success"
    message = result.get("message", "")
    return is_error, message

Unity AI Bridge