diff --git a/agents-api/agents_api/activities/truncation.py b/agents-api/agents_api/activities/truncation.py
index 4742ee6d4..f5a90ee2b 100644
--- a/agents-api/agents_api/activities/truncation.py
+++ b/agents-api/agents_api/activities/truncation.py
@@ -4,57 +4,56 @@
 from temporalio import activity
 
 from agents_api.autogen.openapi_model import Entry
-
-# from agents_api.models.entry.entries_summarization import get_toplevel_entries_query
-
-# TODO: Reimplement truncation queries
-# SCRUM-5
+from agents_api.models.entry.delete_entries import delete_entries
+from agents_api.models.entry.entries_summarization import get_toplevel_entries_query
 
 
 def get_extra_entries(messages: list[Entry], token_count_threshold: int) -> list[UUID]:
-    raise NotImplementedError()
+    result: list[UUID] = []
 
     if not len(messages):
         return messages
 
-    _token_cnt, _offset = 0, 0
-    # if messages[0].role == Role.system:
-    #     token_cnt, offset = messages[0].token_count, 1
+    token_cnt, offset = 0, 0
+    if messages[0].role == "system":
+        token_cnt, offset = messages[0].token_count, 1
 
-    # for m in reversed(messages[offset:]):
-    #     token_cnt += m.token_count
-    #     if token_cnt < token_count_threshold:
-    #         continue
-    #     else:
-    #         result.append(m.id)
+    for m in reversed(messages[offset:]):
+        token_cnt += m.token_count
+        if token_cnt >= token_count_threshold:
+            result.append(m.id)
 
-    # return result
+    return result
 
 
-# TODO: Reimplement truncation activities
-# SCRUM-6
 @activity.defn
 @beartype
-async def truncation(session_id: str, token_count_threshold: int) -> None:
+async def truncation(
+    developer_id: str, session_id: str, token_count_threshold: int
+) -> None:
     session_id = UUID(session_id)
-
-    # delete_entries(
-    #     get_extra_entries(
-    #         [
-    #             Entry(
-    #                 entry_id=row["entry_id"],
-    #                 session_id=session_id,
-    #                 source=row["source"],
-    #                 role=Role(row["role"]),
-    #                 name=row["name"],
-    #                 content=row["content"],
-    #                 created_at=row["created_at"],
-    #                 timestamp=row["timestamp"],
-    #             )
-    #             for _, row in get_toplevel_entries_query(
-    #                 session_id=session_id
-    #             ).iterrows()
-    #         ],
-    #         token_count_threshold,
-    #     ),
-    # )
+    developer_id = UUID(developer_id)
+
+    delete_entries(
+        developer_id=developer_id,
+        session_id=session_id,
+        entry_ids=get_extra_entries(
+            [
+                Entry(
+                    entry_id=row["entry_id"],
+                    session_id=session_id,
+                    source=row["source"],
+                    role=row["role"],
+                    name=row["name"],
+                    content=row["content"],
+                    created_at=row["created_at"],
+                    timestamp=row["timestamp"],
+                    tokenizer=row["tokenizer"],
+                )
+                for _, row in get_toplevel_entries_query(
+                    session_id=session_id
+                ).iterrows()
+            ],
+            token_count_threshold,
+        ),
+    )
diff --git a/agents-api/agents_api/models/entry/entries_summarization.py b/agents-api/agents_api/models/entry/entries_summarization.py
index 899b07730..8fa70fde2 100644
--- a/agents-api/agents_api/models/entry/entries_summarization.py
+++ b/agents-api/agents_api/models/entry/entries_summarization.py
@@ -38,6 +38,7 @@ def get_toplevel_entries_query(session_id: UUID) -> tuple[str, dict]:
         token_count,
         created_at,
         timestamp,
+        tokenizer,
     ] :=
         input[session_id],
         *entries{
@@ -50,6 +51,7 @@ def get_toplevel_entries_query(session_id: UUID) -> tuple[str, dict]:
             token_count,
             created_at,
             timestamp,
+            tokenizer,
         },
         not *relations {
             relation: "summary_of",
diff --git a/agents-api/agents_api/workflows/truncation.py b/agents-api/agents_api/workflows/truncation.py
index d3646ccbe..02649764b 100644
--- a/agents-api/agents_api/workflows/truncation.py
+++ b/agents-api/agents_api/workflows/truncation.py
@@ -12,9 +12,11 @@
 @workflow.defn
 class TruncationWorkflow:
     @workflow.run
-    async def run(self, session_id: str, token_count_threshold: int) -> None:
+    async def run(
+        self, developer_id: str, session_id: str, token_count_threshold: int
+    ) -> None:
         return await workflow.execute_activity(
             truncation,
-            args=[session_id, token_count_threshold],
+            args=[developer_id, session_id, token_count_threshold],
             schedule_to_close_timeout=timedelta(seconds=600),
         )