Add description for Custom Element

Author: koddsson

README.md

@@ -24,6 +24,15 @@ Include with a script tag:
 <script type="module" src="./node_modules/@github/custom-element-element/dist/index.js">
 ```
 
+An example Custom Element. This documentation ends up in the
+README so describe how this elements works here.
+
+You can event add examples on the element is used with Markdown.
+
+```
+<custom-element></custom-element>
+```
+
 ## Browser support
 
 Browsers without native [custom element support][support] require a [polyfill][].

custom-elements.json

@@ -8,7 +8,7 @@
       "declarations": [
         {
           "kind": "class",
-          "description": "",
+          "description": "An example Custom Element. This documentation ends up in the\nREADME so describe how this elements works here.\n\nYou can event add examples on the element is used with Markdown.\n\n```\n<custom-element></custom-element>\n```",
           "name": "CustomElementElement",
           "superclass": {
             "name": "HTMLElement"

src/custom-element.ts

@@ -1,3 +1,13 @@
+/**
+ * An example Custom Element. This documentation ends up in the
+ * README so describe how this elements works here.
+ *
+ * You can event add examples on the element is used with Markdown.
+ *
+ * ```
+ * <custom-element></custom-element>
+ * ```
+ */
 class CustomElementElement extends HTMLElement {
   connectedCallback(): void {
     this.textContent = ':wave:'

vscode.html-custom-data.json

@@ -1,3 +1,9 @@
 {
-  "tags": [{ "name": "custom-element", "description": "", "attributes": [] }]
+  "tags": [
+    {
+      "name": "custom-element",
+      "description": "An example Custom Element. This documentation ends up in the\nREADME so describe how this elements works here.\n\nYou can event add examples on the element is used with Markdown.\n\n```\n<custom-element></custom-element>\n```",
+      "attributes": []
+    }
+  ]
 }