diff --git a/letta/agents/base_agent.py b/letta/agents/base_agent.py
index a349366d..69342758 100644
--- a/letta/agents/base_agent.py
+++ b/letta/agents/base_agent.py
@@ -100,8 +100,10 @@ class BaseAgent(ABC):
 
             # [DB Call] size of messages and archival memories
             # todo: blocking for now
-            num_messages = num_messages or self.message_manager.size(actor=self.actor, agent_id=agent_state.id)
-            num_archival_memories = num_archival_memories or self.passage_manager.size(actor=self.actor, agent_id=agent_state.id)
+            if num_messages is None:
+                num_messages = await self.message_manager.size_async(actor=self.actor, agent_id=agent_state.id)
+            if num_archival_memories is None:
+                num_archival_memories = await self.passage_manager.size_async(actor=self.actor, agent_id=agent_state.id)
 
             new_system_message_str = compile_system_message(
                 system_prompt=agent_state.system,
diff --git a/tests/test_letta_agent_batch.py b/tests/test_letta_agent_batch.py
index da2a6666..bc8f7e8e 100644
--- a/tests/test_letta_agent_batch.py
+++ b/tests/test_letta_agent_batch.py
@@ -1,3 +1,4 @@
+import asyncio
 from datetime import datetime, timezone
 from typing import Tuple
 from unittest.mock import AsyncMock, patch
@@ -481,7 +482,10 @@ async def test_partial_error_from_anthropic_batch(
 
         with patch.object(server.anthropic_async_client.beta.messages.batches, "results", mock_results):
             with patch("letta.llm_api.anthropic_client.AnthropicClient.send_llm_batch_request_async", return_value=dummy_batch_response):
-                msg_counts_before = {agent.id: server.message_manager.size(actor=default_user, agent_id=agent.id) for agent in agents}
+                sizes = await asyncio.gather(
+                    *[server.message_manager.size_async(actor=default_user, agent_id=agent.id) for agent in agents]
+                )
+                msg_counts_before = {agent.id: size for agent, size in zip(agents, sizes)}
 
                 new_batch_responses = await poll_running_llm_batches(server)
 
@@ -545,7 +549,7 @@ async def test_partial_error_from_anthropic_batch(
                 # Tool‑call side‑effects – each agent gets at least 2 extra messages
                 for agent in agents:
                     before = msg_counts_before[agent.id]  # captured just before resume
-                    after = server.message_manager.size(actor=default_user, agent_id=agent.id)
+                    after = await server.message_manager.size_async(actor=default_user, agent_id=agent.id)
 
                     if agent.id == agents_failed[0].id:
                         assert after == before, f"Agent {agent.id} should not have extra messages persisted due to Anthropic failure"
@@ -643,7 +647,10 @@ async def test_resume_step_some_stop(
 
         with patch.object(server.anthropic_async_client.beta.messages.batches, "results", mock_results):
             with patch("letta.llm_api.anthropic_client.AnthropicClient.send_llm_batch_request_async", return_value=dummy_batch_response):
-                msg_counts_before = {agent.id: server.message_manager.size(actor=default_user, agent_id=agent.id) for agent in agents}
+                sizes = await asyncio.gather(
+                    *[server.message_manager.size_async(actor=default_user, agent_id=agent.id) for agent in agents]
+                )
+                msg_counts_before = {agent.id: size for agent, size in zip(agents, sizes)}
 
                 new_batch_responses = await poll_running_llm_batches(server)
 
@@ -703,7 +710,7 @@ async def test_resume_step_some_stop(
                 # Tool‑call side‑effects – each agent gets at least 2 extra messages
                 for agent in agents:
                     before = msg_counts_before[agent.id]  # captured just before resume
-                    after = server.message_manager.size(actor=default_user, agent_id=agent.id)
+                    after = await server.message_manager.size_async(actor=default_user, agent_id=agent.id)
                     assert after - before >= 2, (
                         f"Agent {agent.id} should have an assistant tool‑call " f"and tool‑response message persisted."
                     )
@@ -803,7 +810,10 @@ async def test_resume_step_after_request_all_continue(
 
         with patch.object(server.anthropic_async_client.beta.messages.batches, "results", mock_results):
             with patch("letta.llm_api.anthropic_client.AnthropicClient.send_llm_batch_request_async", return_value=dummy_batch_response):
-                msg_counts_before = {agent.id: server.message_manager.size(actor=default_user, agent_id=agent.id) for agent in agents}
+                sizes = await asyncio.gather(
+                    *[server.message_manager.size_async(actor=default_user, agent_id=agent.id) for agent in agents]
+                )
+                msg_counts_before = {agent.id: size for agent, size in zip(agents, sizes)}
 
                 new_batch_responses = await poll_running_llm_batches(server)
 
@@ -860,7 +870,7 @@ async def test_resume_step_after_request_all_continue(
                 # Tool‑call side‑effects – each agent gets at least 2 extra messages
                 for agent in agents:
                     before = msg_counts_before[agent.id]  # captured just before resume
-                    after = server.message_manager.size(actor=default_user, agent_id=agent.id)
+                    after = await server.message_manager.size_async(actor=default_user, agent_id=agent.id)
                     assert after - before >= 2, (
                         f"Agent {agent.id} should have an assistant tool‑call " f"and tool‑response message persisted."
                     )