--- slug: python-reference/LettaMessage --- ## LettaMessage ```python class LettaMessage(BaseModel) ``` Base class for simplified Letta message response type. This is intended to be used for developers who want the internal monologue, function calls, and function returns in a simplified format that does not include additional information other than the content and timestamp. **Attributes**: - `id` _str_ - The ID of the message - `date` _datetime_ - The date the message was created in ISO format ## InternalMonologue ```python class InternalMonologue(LettaMessage) ``` Representation of an agent's internal monologue. **Attributes**: - `internal_monologue` _str_ - The internal monologue of the agent - `id` _str_ - The ID of the message - `date` _datetime_ - The date the message was created in ISO format ## FunctionCallMessage ```python class FunctionCallMessage(LettaMessage) ``` A message representing a request to call a function (generated by the LLM to trigger function execution). **Attributes**: - `function_call` _Union[FunctionCall, FunctionCallDelta]_ - The function call - `id` _str_ - The ID of the message - `date` _datetime_ - The date the message was created in ISO format ## FunctionReturn ```python class FunctionReturn(LettaMessage) ``` A message representing the return value of a function call (generated by Letta executing the requested function). **Attributes**: - `function_return` _str_ - The return value of the function - `status` _Literal["success", "error"]_ - The status of the function call - `id` _str_ - The ID of the message - `date` _datetime_ - The date the message was created in ISO format