Generate dedicated Python session event types

docs/setup/local-cli.md

@@ -99,7 +99,11 @@ func main() {
 
 	session, _ := client.CreateSession(ctx, &copilot.SessionConfig{Model: "gpt-4.1"})
 	response, _ := session.SendAndWait(ctx, copilot.MessageOptions{Prompt: "Hello!"})
-	fmt.Println(*response.Data.Content)
+	if response != nil {
+		if d, ok := response.Data.(*copilot.AssistantMessageData); ok {
+			fmt.Println(d.Content)
+		}
+	}
 }
 ```
 <!-- /docs-validate: hidden -->
@@ -115,7 +119,11 @@ defer client.Stop()
 
 session, _ := client.CreateSession(ctx, &copilot.SessionConfig{Model: "gpt-4.1"})
 response, _ := session.SendAndWait(ctx, copilot.MessageOptions{Prompt: "Hello!"})
-fmt.Println(*response.Data.Content)
+if response != nil {
+    if d, ok := response.Data.(*copilot.AssistantMessageData); ok {
+        fmt.Println(d.Content)
+    }
+}
 ```
 
 </details>

python/README.md

@@ -25,8 +25,10 @@ python chat.py
 
 ```python
 import asyncio
+from typing import cast
+
 from copilot import CopilotClient
-from copilot.session import PermissionHandler
+from copilot.generated.session_events import AssistantMessageData
 
 async def main():
     # Client automatically starts on enter and cleans up on exit
@@ -38,7 +40,7 @@ async def main():
 
             def on_event(event):
                 if event.type.value == "assistant.message":
-                    print(event.data.content)
+                    print(cast(AssistantMessageData, event.data).content)
                 elif event.type.value == "session.idle":
                     done.set()
 
@@ -57,7 +59,10 @@ If you need more control over the lifecycle, you can call `start()`, `stop()`, a
 
 ```python
 import asyncio
+from typing import cast
+
 from copilot import CopilotClient
+from copilot.generated.session_events import AssistantMessageData
 from copilot.session import PermissionHandler
 
 async def main():
@@ -74,7 +79,7 @@ async def main():
 
     def on_event(event):
         if event.type.value == "assistant.message":
-            print(event.data.content)
+            print(cast(AssistantMessageData, event.data).content)
         elif event.type.value == "session.idle":
             done.set()
 
@@ -333,7 +338,15 @@ Enable streaming to receive assistant response chunks as they're generated:
 
 ```python
 import asyncio
+from typing import cast
+
 from copilot import CopilotClient
+from copilot.generated.session_events import (
+    AssistantMessageData,
+    AssistantMessageDeltaData,
+    AssistantReasoningData,
+    AssistantReasoningDeltaData,
+)
 from copilot.session import PermissionHandler
 
 async def main():
@@ -350,20 +363,20 @@ async def main():
                 match event.type.value:
                     case "assistant.message_delta":
                         # Streaming message chunk - print incrementally
-                        delta = event.data.delta_content or ""
+                        delta = cast(AssistantMessageDeltaData, event.data).delta_content or ""
                         print(delta, end="", flush=True)
                     case "assistant.reasoning_delta":
                         # Streaming reasoning chunk (if model supports reasoning)
-                        delta = event.data.delta_content or ""
+                        delta = cast(AssistantReasoningDeltaData, event.data).delta_content or ""
                         print(delta, end="", flush=True)
                     case "assistant.message":
                         # Final message - complete content
                         print("\n--- Final message ---")
-                        print(event.data.content)
+                        print(cast(AssistantMessageData, event.data).content)
                     case "assistant.reasoning":
                         # Final reasoning content (if model supports reasoning)
                         print("--- Reasoning ---")
-                        print(event.data.content)
+                        print(cast(AssistantReasoningData, event.data).content)
                     case "session.idle":
                         # Session finished processing
                         done.set()