chore: import upstream snapshot with attribution

python/samples/02-agents/compaction/custom.py

@@ -0,0 +1,83 @@
+# Copyright (c) Microsoft. All rights reserved.
+
+import asyncio
+
+from agent_framework import (
+    Message,
+    annotate_message_groups,
+    apply_compaction,
+    included_messages,
+)
+
+"""This sample demonstrates authoring a custom compaction strategy.
+
+The custom strategy keeps system messages and the most recent user turn while
+excluding older non-system groups.
+"""
+
+EXCLUDED_KEY = "_excluded"
+GROUP_ANNOTATION_KEY = "_group"
+
+
+class KeepLastUserTurnStrategy:
+    async def __call__(self, messages: list[Message]) -> bool:
+        group_ids = annotate_message_groups(messages)
+        group_kinds: dict[str, str] = {}
+        for message in messages:
+            group_annotation = message.additional_properties.get(GROUP_ANNOTATION_KEY)
+            group_id = group_annotation.get("id") if isinstance(group_annotation, dict) else None
+            kind = group_annotation.get("kind") if isinstance(group_annotation, dict) else None
+            if isinstance(group_id, str) and isinstance(kind, str) and group_id not in group_kinds:
+                group_kinds[group_id] = kind
+        user_group_ids = [group_id for group_id in group_ids if group_kinds.get(group_id) == "user"]
+        if not user_group_ids:
+            return False
+        keep_user_group_id = user_group_ids[-1]
+
+        changed = False
+        for message in messages:
+            group_annotation = message.additional_properties.get(GROUP_ANNOTATION_KEY)
+            group_id = group_annotation.get("id") if isinstance(group_annotation, dict) else None
+            if message.role == "system":
+                continue
+            if group_id == keep_user_group_id:
+                continue
+            if message.additional_properties.get(EXCLUDED_KEY) is not True:
+                changed = True
+            message.additional_properties[EXCLUDED_KEY] = True
+        return changed
+
+
+def _messages() -> list[Message]:
+    return [
+        Message(role="system", contents=["You are concise."]),
+        Message(role="user", contents=["first request"]),
+        Message(role="assistant", contents=["first response"]),
+        Message(role="user", contents=["second request"]),
+        Message(role="assistant", contents=["second response"]),
+    ]
+
+
+async def main() -> None:
+    # 1. Build a short conversation.
+    messages = _messages()
+    print(f"Number of messages before compaction: {len(messages)}")
+    # 2. Apply custom strategy.
+    await apply_compaction(messages, strategy=KeepLastUserTurnStrategy())
+    # 3. Print projected messages.
+    projected = included_messages(messages)
+    print(f"Number of messages after compaction: {len(projected)}")
+    for msg in projected:
+        print(f"[{msg.role}] {msg.text}")
+
+
+if __name__ == "__main__":
+    asyncio.run(main())
+
+"""
+Sample output:
+Number of messages before compaction: 5
+Number of messages after compaction: 2
+[system] You are concise.
+[user] second request
+"""