Add input/output example to readme

README.md

@@ -28,6 +28,60 @@ currently open), you can replace parts of the JSON document (anything
 except object keys) with [Jinja2 templates][jinja], from which you can
 invoke custom plugins, which look up and return your dynamic content.
 
+<table>
+<thead>
+<tr>
+<td>Input</td>
+<td>Output</td>
+</tr>
+</thead>
+<tbody>
+<tr>
+<td>
+
+```json
+{
+  "api": "0.13",
+  "space": "My Hackerspace",
+  "state": "{{ space_state() }}",
+  "sensors": {
+    "network_connections": "{{ network_connections() }}"
+  }
+}
+```
+
+</td>
+<td>
+
+```json
+{
+  "api": "0.13",
+  "state": {
+    "open": true,
+    "lastchange": 1575160777,
+    "message": "Visitors Welcome!"
+  },
+  "sensors": {
+    "network_connections": [
+      {
+        "value": 4,
+        "type": "wifi",
+        "name": "2.4 GHz"
+      },
+      {
+        "value": 7,
+        "type": "wifi",
+        "name": "5 GHz"
+      }
+    ]
+  }
+}
+```
+</td>
+</tr>
+</tbody>
+</table>
+
 ## Usage
 
 ### 0. Download