diff --git a/letta/orm/message.py b/letta/orm/message.py
index 770ae8d7..d9808547 100644
--- a/letta/orm/message.py
+++ b/letta/orm/message.py
@@ -104,6 +104,7 @@ class Message(SqlalchemyBase, OrganizationMixin, AgentMixin):
             and len(self.content) == 1
             and isinstance(self.content[0], TextContent)
         ):
+            self.tool_call_id = self.tool_returns[0].tool_call_id
             self.tool_returns[0].func_response = self.content[0].text
 
         return model
diff --git a/letta/schemas/message.py b/letta/schemas/message.py
index 3ce86d86..36d592cc 100644
--- a/letta/schemas/message.py
+++ b/letta/schemas/message.py
@@ -883,6 +883,12 @@ class Message(BaseMessage):
             [TextContent(text=openai_message_dict["content"])] if openai_message_dict["content"] else []
         )
 
+        # This is really hacky and this interface is poorly designed, we should auto derive tool_returns instead of passing it in
+        if not tool_returns:
+            tool_returns = []
+            if "tool_returns" in openai_message_dict:
+                tool_returns = [ToolReturn(**tr) for tr in openai_message_dict["tool_returns"]]
+
         # TODO(caren) bad assumption here that "reasoning_content" always comes before "redacted_reasoning_content"
         if "reasoning_content" in openai_message_dict and openai_message_dict["reasoning_content"]:
             content.append(
@@ -1481,19 +1487,33 @@ class Message(BaseMessage):
 
         elif self.role == "tool":
             # NOTE: Anthropic uses role "user" for "tool" responses
-            assert self.tool_call_id is not None, vars(self)
-            anthropic_message = {
-                "role": "user",  # NOTE: diff
-                "content": [
-                    # TODO support error types etc
+            content = []
+            for tool_return in self.tool_returns:
+                content.append(
                     {
                         "type": "tool_result",
-                        "tool_use_id": self.tool_call_id,
-                        "content": text_content,
+                        "tool_use_id": tool_return.tool_call_id,
+                        "content": tool_return.func_response,
                     }
-                ],
-            }
-
+                )
+            if content:
+                anthropic_message = {
+                    "role": "user",
+                    "content": content,
+                }
+            else:
+                # This is for legacy reasons
+                anthropic_message = {
+                    "role": "user",  # NOTE: diff
+                    "content": [
+                        # TODO support error types etc
+                        {
+                            "type": "tool_result",
+                            "tool_use_id": self.tool_call_id,
+                            "content": text_content,
+                        }
+                    ],
+                }
         else:
             raise ValueError(self.role)
 
diff --git a/letta/services/helpers/agent_manager_helper.py b/letta/services/helpers/agent_manager_helper.py
index ffa424a9..e9c74e40 100644
--- a/letta/services/helpers/agent_manager_helper.py
+++ b/letta/services/helpers/agent_manager_helper.py
@@ -38,7 +38,7 @@ from letta.schemas.embedding_config import EmbeddingConfig
 from letta.schemas.enums import AgentType, MessageRole
 from letta.schemas.letta_message_content import TextContent
 from letta.schemas.memory import Memory
-from letta.schemas.message import Message, MessageCreate
+from letta.schemas.message import Message, MessageCreate, ToolReturn
 from letta.schemas.tool_rule import ToolRule
 from letta.schemas.user import User
 from letta.settings import DatabaseChoice, settings
@@ -536,6 +536,13 @@ def package_initial_message_sequence(
                     agent_id=agent_id,
                     model=model,
                     tool_call_id=tool_call_id,
+                    tool_returns=[
+                        ToolReturn(
+                            tool_call_id=tool_call_id,
+                            status="success",
+                            func_response=function_response,
+                        )
+                    ],
                 )
             )
         else:
diff --git a/letta/system.py b/letta/system.py
index ec3cda2c..59ddc321 100644
--- a/letta/system.py
+++ b/letta/system.py
@@ -42,11 +42,17 @@ def get_initial_boot_messages(version, timezone, tool_call_id):
             },
             # obligatory function return message
             {
-                # "role": "function",
                 "role": "tool",
                 "name": "send_message",  # NOTE: technically not up to spec, this is old functions style
                 "content": package_function_response(True, None, timezone),
                 "tool_call_id": tool_call_id,
+                "tool_returns": [
+                    {
+                        "tool_call_id": tool_call_id,
+                        "status": "success",
+                        "func_response": package_function_response(True, None, timezone),
+                    }
+                ],
             },
         ]