feat: Step 6 MCP server bridge for AI agents

- Add ModelContextProtocol + ModelContextProtocol.AspNetCore 1.4.0 to Engine.AI. - Expose AI commands as MCP tools: spawn_model, set_transform, delete_entity, list_entities. - Add AiCommandQueue to marshal commands from the MCP server thread to the main thread. - Start in-process HTTP MCP server in Program.cs (Debug/Release only; excluded in ReleaseAOT). - Add --mcp-port CLI argument to configure the MCP server port. - Fix Flecs.NET package conditions to include ReleaseAOT config.
2026-06-16 19:59:19 +03:00
parent 2f21ffada4
commit a9c783d204
8 changed files with 314 additions and 20 deletions
@@ -0,0 +1,124 @@
+using System.ComponentModel;
+using System.Numerics;
+using Engine.AI.Commands;
+using ModelContextProtocol.Server;
+
+namespace Engine.AI.Mcp;
+
+/// <summary>
+/// MCP tools that expose engine commands to AI agents.
+/// </summary>
+[McpServerToolType]
+public sealed class EngineMcpTools
+{
+    private readonly AiCommandQueue _queue;
+
+    public EngineMcpTools(AiCommandQueue queue)
+    {
+        _queue = queue;
+    }
+
+    [McpServerTool, Description("Spawn a 3D model entity in the engine world.")]
+    public Task<string> SpawnModel(
+        string name,
+        string modelPath,
+        [Description("Optional position as [x, y, z] (default: 0,0,0)")] IReadOnlyList<double>? position = null,
+        [Description("Optional rotation as [x, y, z, w] quaternion (default: identity)")] IReadOnlyList<double>? rotation = null,
+        [Description("Optional scale as [x, y, z] (default: 1,1,1)")] IReadOnlyList<double>? scale = null)
+    {
+        var cmd = new SpawnModelCommand
+        {
+            Name = name,
+            ModelPath = modelPath,
+            Position = ToVector3(position, Vector3.Zero),
+            Rotation = ToQuaternion(rotation, Quaternion.Identity),
+            Scale = ToVector3(scale, Vector3.One)
+        };
+
+        return EnqueueAndReturnMessage(cmd);
+    }
+
+    [McpServerTool, Description("Update the transform of an existing entity by name.")]
+    public Task<string> SetTransform(
+        string name,
+        [Description("Optional position as [x, y, z]")] IReadOnlyList<double>? position = null,
+        [Description("Optional rotation as [x, y, z, w] quaternion")] IReadOnlyList<double>? rotation = null,
+        [Description("Optional scale as [x, y, z]")] IReadOnlyList<double>? scale = null)
+    {
+        var cmd = new SetTransformCommand
+        {
+            Name = name,
+            Position = ToVector3(position),
+            Rotation = ToQuaternion(rotation),
+            Scale = ToVector3(scale)
+        };
+
+        return EnqueueAndReturnMessage(cmd);
+    }
+
+    [McpServerTool, Description("Delete an entity by name.")]
+    public Task<string> DeleteEntity(string name)
+    {
+        var cmd = new DeleteEntityCommand { Name = name };
+        return EnqueueAndReturnMessage(cmd);
+    }
+
+    [McpServerTool, Description("List all named entities in the ECS world.")]
+    public Task<string> ListEntities()
+    {
+        var cmd = new ListEntitiesCommand();
+        return EnqueueAndReturnMessage(cmd);
+    }
+
+    private async Task<string> EnqueueAndReturnMessage(AiCommand command)
+    {
+        var result = await _queue.EnqueueAsync(command).ConfigureAwait(false);
+        return result.Success
+            ? result.Message
+            : throw new InvalidOperationException(result.Message);
+    }
+
+    private static Vector3 ToVector3(IReadOnlyList<double>? values, Vector3 defaultValue)
+    {
+        if (values == null || values.Count == 0)
+            return defaultValue;
+
+        if (values.Count != 3)
+            throw new ArgumentException("Expected 3 values for Vector3.", nameof(values));
+
+        return new Vector3((float)values[0], (float)values[1], (float)values[2]);
+    }
+
+    private static Vector3? ToVector3(IReadOnlyList<double>? values)
+    {
+        if (values == null || values.Count == 0)
+            return null;
+
+        if (values.Count != 3)
+            throw new ArgumentException("Expected 3 values for Vector3.", nameof(values));
+
+        return new Vector3((float)values[0], (float)values[1], (float)values[2]);
+    }
+
+    private static Quaternion ToQuaternion(IReadOnlyList<double>? values, Quaternion defaultValue)
+    {
+        if (values == null || values.Count == 0)
+            return defaultValue;
+
+        if (values.Count != 4)
+            throw new ArgumentException("Expected 4 values for Quaternion.", nameof(values));
+
+        return new Quaternion((float)values[0], (float)values[1], (float)values[2], (float)values[3]);
+    }
+
+    private static Quaternion? ToQuaternion(IReadOnlyList<double>? values)
+    {
+        if (values == null || values.Count == 0)
+            return null;
+
+        if (values.Count != 4)
+            throw new ArgumentException("Expected 4 values for Quaternion.", nameof(values));
+
+        return new Quaternion((float)values[0], (float)values[1], (float)values[2], (float)values[3]);
+    }
+}