feat: update McpUiAppToolConfig to support both _meta.ui and flat formats

Author: ochafik

src/generated/schema.json

@@ -7,6 +7,7 @@
 import {
   RESOURCE_URI_META_KEY as _RESOURCE_URI_META_KEY,
   McpUiResourceMeta,
+  McpUiToolMeta,
   RESOURCE_MIME_TYPE,
 } from "../app.js";
 import type {
@@ -41,17 +42,18 @@ export interface ToolConfig {
  */
 export interface McpUiAppToolConfig extends ToolConfig {
   _meta: {
-    // Soon: `ui: McpUiToolMeta;` (https://github.com/modelcontextprotocol/ext-apps/pull/131)
-
+    [key: string]: unknown;
+  } & ({
+    ui: McpUiToolMeta;
+  } | {
     /**
      * URI of the UI resource to display for this tool.
      * This is converted to `_meta["ui/resourceUri"]`.
      *
      * @example "ui://weather/widget.html"
      */
     [RESOURCE_URI_META_KEY]?: string;
-    [key: string]: unknown;
-  };
+  });
 }
 
 /**

src/generated/schema.ts

@@ -524,7 +524,7 @@ export type McpUiToolVisibility = "model" | "app";
  */
 export interface McpUiToolMeta {
   /** @description URI of UI resource for rendering tool results. */
-  resourceUri?: string;
+  resourceUri: string;
   /**
    * @description Who can access this tool. Default: ["model", "app"]
    * - "model": Tool visible to and callable by the agent