Add createPrefabTool MCP server tool wrapper

CoderGamester · CoderGamester · commit ec57b2ab9356 · 2025-08-06T22:30:37.000+03:00
Implemented the MCP server side TypeScript tool wrapper createPrefabTool.ts for the CreatePrefabTool, including parameter validation, error handling, and communication with Unity Editor.
diff --git a/Server~/src/tools/createPrefabTool.ts b/Server~/src/tools/createPrefabTool.ts
@@ -0,0 +1,91 @@
+import { McpServer } from '@modelcontextprotocol/sdk/server/mcp.js';
+import { McpUnity } from '../unity/mcpUnity.js';
+import { McpUnityError, ErrorType } from '../utils/errors.js';
+import * as z from 'zod';
+import { Logger } from '../utils/logger.js';
+
+// Constants for the tool
+const toolName = 'create_prefab';
+const toolDescription = 'Creates a prefab with optional MonoBehaviour script and serialized field values';
+
+// Parameter schema for the tool
+const paramsSchema = z.object({
+  scriptName: z.string().optional().describe('The name of the MonoBehaviour script class (optional)'),
+  prefabName: z.string().describe('The name of the prefab to create'),
+  fieldValues: z.record(z.any()).optional().describe('Optional JSON object of serialized field values to apply to the prefab')
+});
+
+/**
+ * Creates and registers the CreatePrefab tool with the MCP server
+ * 
+ * @param server The MCP server to register the tool with
+ * @param mcpUnity The McpUnity instance to communicate with Unity
+ * @param logger The logger instance for diagnostic information
+ */
+export function registerCreatePrefabTool(server: McpServer, mcpUnity: McpUnity, logger: Logger) {
+  logger.info(`Registering tool: ${toolName}`);
+  
+  server.tool(
+    toolName,
+    toolDescription,
+    paramsSchema.shape,
+    async (params: any) => {
+      try {
+        logger.info(`Executing tool: ${toolName}`, params);
+        const result = await toolHandler(mcpUnity, params);
+        logger.info(`Tool execution successful: ${toolName}`);
+        return result;
+      } catch (error) {
+        logger.error(`Tool execution failed: ${toolName}`, error);
+        throw error;
+      }
+    }
+  );
+}
+
+/**
+ * Handler function for the CreatePrefab tool
+ * 
+ * @param mcpUnity The McpUnity instance to communicate with Unity
+ * @param params The validated parameters for the tool
+ * @returns A promise that resolves to the tool execution result
+ * @throws McpUnityError if validation fails or the request to Unity fails
+ */
+async function toolHandler(mcpUnity: McpUnity, params: any) {  
+  if (!params.scriptName) {
+    throw new McpUnityError(
+      ErrorType.VALIDATION,
+      "'scriptName' must be provided"
+    );
+  }
+  
+  if (!params.prefabName) {
+    throw new McpUnityError(
+      ErrorType.VALIDATION,
+      "'prefabName' must be provided"
+    );
+  }
+  
+  const response = await mcpUnity.sendRequest({
+    method: toolName,
+    params
+  });
+  
+  if (!response.success) {
+    throw new McpUnityError(
+      ErrorType.TOOL_EXECUTION,
+      response.message || `Failed to create prefab`
+    );
+  }
+  
+  return {
+    content: [{
+      type: response.type,
+      text: response.message || `Successfully created prefab`
+    }],
+    // Include the prefab path in the result for programmatic access
+    data: {
+      prefabPath: response.prefabPath
+    }
+  };
+}
