Updated protocol schema to add context sharing support

specs/activity/protocol-activity.md

@@ -1952,6 +1952,7 @@ Activity [entities](#entity) communicate extra metadata about the activity, such
 | number         | N/A                                     | Number                    |
 | clientInfo     | N/A                                     | Skype client info         |
 | streamInfo     | N/A                                     | Streaming text metadata   |
+| context        | N/A                                     | Query context details     |
 
 ### string and number
 
@@ -2200,6 +2201,32 @@ Voice streaming uses `event` activities with [Media.* events](#reserved-events-f
 }
 ```
 
+### context
+The context entity contains contextual information between users and agents to improve understanding of ongoing conversations. This enables more relevant, personalized, and accurate responses, especially in multimodal interactions. By embedding context directly in the activity message, agents can leverage contextual information such as images, custom objects, and audio/video-related context.
+
+The context entity in an activity message can contain a `screenContext` object. This can be a list of screenshots of the page the user is currently on. The images are shared either in base64-encoded format or as a URL.
+
+`A9263`: If the context contains no elements, it should be ignored.
+
+`A9264`: If the context entity contains any syntactic errors, it should be ignored by the recipient to prevent processing invalid data.
+
+```
+  // Sending context information as part of the activity message
+  {
+    "type": "message",
+    "text": "What pizzas are available for $150?",
+    "entities": [
+      {
+        "type": "context",
+        "screenContext": {
+          "images": ["iVBORw0KGgoAAAANSUhEUgAAAAUA...", "https://example.com/product-page"] // a list of base64-encoded image or URL that should be used as context.
+        }
+      }
+    ]
+  }
+```
+
+
 # Appendix III - Protocols using the Invoke activity
 
 The [invoke activity](#invoke-activity) is designed for use only within protocols supported by Activity Protocol channels (i.e., it is not a generic extensibility mechanism). This appendix contains a list of all protocols using this activity.