letta-server/letta/functions/function_sets/base.py

from typing import List, Literal, Optional

from letta.agent import Agent
from letta.constants import CORE_MEMORY_LINE_NUMBER_WARNING


def send_message(self: "Agent", message: str) -> Optional[str]:
    """
    Sends a message to the human user.

    Args:
        message (str): Message contents. All unicode (including emojis) are supported.

    Returns:
        Optional[str]: None is always returned as this function does not produce a response.
    """
    # FIXME passing of msg_obj here is a hack, unclear if guaranteed to be the correct reference
    if self.interface:
        self.interface.assistant_message(message)  # , msg_obj=self._messages[-1])
    return None


def conversation_search(
    self: "Agent",
    query: str,
    roles: Optional[List[Literal["assistant", "user", "tool"]]] = None,
    limit: Optional[int] = None,
    start_date: Optional[str] = None,
    end_date: Optional[str] = None,
) -> Optional[str]:
    """
    Search prior conversation history using hybrid search (text + semantic similarity).

    Args:
        query (str): String to search for using both text matching and semantic similarity.
        roles (Optional[List[Literal["assistant", "user", "tool"]]]): Optional list of message roles to filter by.
        limit (Optional[int]): Maximum number of results to return. Uses system default if not specified.
        start_date (Optional[str]): Filter results to messages created on or after this date (INCLUSIVE). When using date-only format (e.g., "2024-01-15"), includes messages starting from 00:00:00 of that day. ISO 8601 format: "YYYY-MM-DD" or "YYYY-MM-DDTHH:MM". Examples: "2024-01-15" (from start of Jan 15), "2024-01-15T14:30" (from 2:30 PM on Jan 15).
        end_date (Optional[str]): Filter results to messages created on or before this date (INCLUSIVE). When using date-only format (e.g., "2024-01-20"), includes all messages from that entire day. ISO 8601 format: "YYYY-MM-DD" or "YYYY-MM-DDTHH:MM". Examples: "2024-01-20" (includes all of Jan 20), "2024-01-20T17:00" (up to 5 PM on Jan 20).

    Examples:
        # Search all messages
        conversation_search(query="project updates")

        # Search only assistant messages
        conversation_search(query="error handling", roles=["assistant"])

        # Search with date range (inclusive of both dates)
        conversation_search(query="meetings", start_date="2024-01-15", end_date="2024-01-20")
        # This includes all messages from Jan 15 00:00:00 through Jan 20 23:59:59

        # Search messages from a specific day (inclusive)
        conversation_search(query="bug reports", start_date="2024-09-04", end_date="2024-09-04")
        # This includes ALL messages from September 4, 2024

        # Search with specific time boundaries
        conversation_search(query="deployment", start_date="2024-01-15T09:00", end_date="2024-01-15T17:30")
        # This includes messages from 9 AM to 5:30 PM on Jan 15

        # Search with limit
        conversation_search(query="debugging", limit=10)

    Returns:
        str: Query result string containing matching messages with timestamps and content.
    """

    from letta.constants import RETRIEVAL_QUERY_DEFAULT_PAGE_SIZE
    from letta.helpers.json_helpers import json_dumps

    # Use provided limit or default
    if limit is None:
        limit = RETRIEVAL_QUERY_DEFAULT_PAGE_SIZE

    messages = self.message_manager.list_messages_for_agent(
        agent_id=self.agent_state.id,
        actor=self.user,
        query_text=query,
        roles=roles,
        limit=limit,
    )

    if len(messages) == 0:
        results_str = "No results found."
    else:
        results_pref = f"Found {len(messages)} results:"
        results_formatted = []
        for message in messages:
            # Extract text content from message
            text_content = message.content[0].text if message.content else ""
            result_entry = {"role": message.role, "content": text_content}
            results_formatted.append(result_entry)
        results_str = f"{results_pref} {json_dumps(results_formatted)}"
    return results_str


async def archival_memory_insert(self: "Agent", content: str, tags: Optional[list[str]] = None) -> Optional[str]:
    """
    Add to archival memory. Make sure to phrase the memory contents such that it can be easily queried later.

    Args:
        content (str): Content to write to the memory. All unicode (including emojis) are supported.
        tags (Optional[list[str]]): Optional list of tags to associate with this memory for better organization and filtering.

    Returns:
        Optional[str]: None is always returned as this function does not produce a response.
    """
    raise NotImplementedError("This should never be invoked directly. Contact Letta if you see this error message.")


async def archival_memory_search(
    self: "Agent",
    query: str,
    tags: Optional[list[str]] = None,
    tag_match_mode: Literal["any", "all"] = "any",
    top_k: Optional[int] = None,
    start_datetime: Optional[str] = None,
    end_datetime: Optional[str] = None,
) -> Optional[str]:
    """
    Search archival memory using semantic (embedding-based) search with optional temporal filtering.

    Args:
        query (str): String to search for using semantic similarity.
        tags (Optional[list[str]]): Optional list of tags to filter search results. Only passages with these tags will be returned.
        tag_match_mode (Literal["any", "all"]): How to match tags - "any" to match passages with any of the tags, "all" to match only passages with all tags. Defaults to "any".
        top_k (Optional[int]): Maximum number of results to return. Uses system default if not specified.
        start_datetime (Optional[str]): Filter results to passages created on or after this datetime (INCLUSIVE). When using date-only format (e.g., "2024-01-15"), includes passages starting from 00:00:00 of that day. ISO 8601 format: "YYYY-MM-DD" or "YYYY-MM-DDTHH:MM". Examples: "2024-01-15" (from start of Jan 15), "2024-01-15T14:30" (from 2:30 PM on Jan 15).
        end_datetime (Optional[str]): Filter results to passages created on or before this datetime (INCLUSIVE). When using date-only format (e.g., "2024-01-20"), includes all passages from that entire day. ISO 8601 format: "YYYY-MM-DD" or "YYYY-MM-DDTHH:MM". Examples: "2024-01-20" (includes all of Jan 20), "2024-01-20T17:00" (up to 5 PM on Jan 20).

    Examples:
        # Search all passages
        archival_memory_search(query="project updates")

        # Search with date range (inclusive of both dates)
        archival_memory_search(query="meetings", start_datetime="2024-01-15", end_datetime="2024-01-20")
        # This includes all passages from Jan 15 00:00:00 through Jan 20 23:59:59

        # Search passages from a specific day (inclusive)
        archival_memory_search(query="bug reports", start_datetime="2024-09-04", end_datetime="2024-09-04")
        # This includes ALL passages from September 4, 2024

        # Search with specific time range
        archival_memory_search(query="error logs", start_datetime="2024-01-15T09:30", end_datetime="2024-01-15T17:30")
        # This includes passages from 9:30 AM to 5:30 PM on Jan 15

        # Search from a specific point in time onwards
        archival_memory_search(query="customer feedback", start_datetime="2024-01-15T14:00")

    Returns:
        str: Query result string containing matching passages with timestamps and content.
    """
    raise NotImplementedError("This should never be invoked directly. Contact Letta if you see this error message.")


def core_memory_append(agent_state: "AgentState", label: str, content: str) -> Optional[str]:  # type: ignore
    """
    Append to the contents of core memory.

    Args:
        label (str): Section of the memory to be edited.
        content (str): Content to write to the memory. All unicode (including emojis) are supported.

    Returns:
        Optional[str]: None is always returned as this function does not produce a response.
    """
    current_value = str(agent_state.memory.get_block(label).value)
    new_value = current_value + "\n" + str(content)
    agent_state.memory.update_block_value(label=label, value=new_value)
    return None


def core_memory_replace(agent_state: "AgentState", label: str, old_content: str, new_content: str) -> Optional[str]:  # type: ignore
    """
    Replace the contents of core memory. To delete memories, use an empty string for new_content.

    Args:
        label (str): Section of the memory to be edited.
        old_content (str): String to replace. Must be an exact match.
        new_content (str): Content to write to the memory. All unicode (including emojis) are supported.

    Returns:
        Optional[str]: None is always returned as this function does not produce a response.
    """
    current_value = str(agent_state.memory.get_block(label).value)
    if old_content not in current_value:
        raise ValueError(f"Old content '{old_content}' not found in memory block '{label}'")
    new_value = current_value.replace(str(old_content), str(new_content))
    agent_state.memory.update_block_value(label=label, value=new_value)
    return None


def rethink_memory(agent_state: "AgentState", new_memory: str, target_block_label: str) -> None:
    """
    Rewrite memory block for the main agent, new_memory should contain all current information from the block that is not outdated or inconsistent, integrating any new information, resulting in a new memory block that is organized, readable, and comprehensive.

    Args:
        new_memory (str): The new memory with information integrated from the memory block. If there is no new information, then this should be the same as the content in the source block.
        target_block_label (str): The name of the block to write to.

    Returns:
        None: None is always returned as this function does not produce a response.
    """

    if agent_state.memory.get_block(target_block_label) is None:
        agent_state.memory.create_block(label=target_block_label, value=new_memory)

    agent_state.memory.update_block_value(label=target_block_label, value=new_memory)
    return None


## Attempted v2 of sleep-time function set, meant to work better across all types

SNIPPET_LINES: int = 4


# Based off of: https://github.com/anthropics/anthropic-quickstarts/blob/main/computer-use-demo/computer_use_demo/tools/edit.py?ref=musings.yasyf.com#L154
def memory_replace(agent_state: "AgentState", label: str, old_str: str, new_str: str) -> str:  # type: ignore
    """
    The memory_replace command allows you to replace a specific string in a memory block with a new string. This is used for making precise edits.

    Args:
        label (str): Section of the memory to be edited, identified by its label.
        old_str (str): The text to replace (must match exactly, including whitespace and indentation).
        new_str (str): The new text to insert in place of the old text. Do not include line number prefixes.

    Examples:
        # Update a block containing information about the user
        memory_replace(label="human", old_str="Their name is Alice", new_str="Their name is Bob")

        # Update a block containing a todo list
        memory_replace(label="todos", old_str="- [ ] Step 5: Search the web", new_str="- [x] Step 5: Search the web")

        # Pass an empty string to
        memory_replace(label="human", old_str="Their name is Alice", new_str="")

        # Bad example - do NOT add (view-only) line numbers to the args
        memory_replace(label="human", old_str="Line 1: Their name is Alice", new_str="Line 1: Their name is Bob")

        # Bad example - do NOT include the number number warning either
        memory_replace(label="human", old_str="# NOTE: Line numbers shown below are to help during editing. Do NOT include line number prefixes in your memory edit tool calls.\\nLine 1: Their name is Alice", new_str="Line 1: Their name is Bob")

        # Good example - no line numbers or line number warning (they are view-only), just the text
        memory_replace(label="human", old_str="Their name is Alice", new_str="Their name is Bob")

    Returns:
        str: The success message
    """
    import re

    if bool(re.search(r"\nLine \d+: ", old_str)):
        raise ValueError(
            "old_str contains a line number prefix, which is not allowed. Do not include line numbers when calling memory tools (line numbers are for display purposes only)."
        )
    if CORE_MEMORY_LINE_NUMBER_WARNING in old_str:
        raise ValueError(
            "old_str contains a line number warning, which is not allowed. Do not include line number information when calling memory tools (line numbers are for display purposes only)."
        )
    if bool(re.search(r"\nLine \d+: ", new_str)):
        raise ValueError(
            "new_str contains a line number prefix, which is not allowed. Do not include line numbers when calling memory tools (line numbers are for display purposes only)."
        )

    old_str = str(old_str).expandtabs()
    new_str = str(new_str).expandtabs()
    current_value = str(agent_state.memory.get_block(label).value).expandtabs()

    # Check if old_str is unique in the block
    occurences = current_value.count(old_str)
    if occurences == 0:
        raise ValueError(f"No replacement was performed, old_str `{old_str}` did not appear verbatim in memory block with label `{label}`.")
    elif occurences > 1:
        content_value_lines = current_value.split("\n")
        lines = [idx + 1 for idx, line in enumerate(content_value_lines) if old_str in line]
        raise ValueError(
            f"No replacement was performed. Multiple occurrences of old_str `{old_str}` in lines {lines}. Please ensure it is unique."
        )

    # Replace old_str with new_str
    new_value = current_value.replace(str(old_str), str(new_str))

    # Write the new content to the block
    agent_state.memory.update_block_value(label=label, value=new_value)

    # Create a snippet of the edited section
    # SNIPPET_LINES = 3
    # replacement_line = current_value.split(old_str)[0].count("\n")
    # start_line = max(0, replacement_line - SNIPPET_LINES)
    # end_line = replacement_line + SNIPPET_LINES + new_str.count("\n")
    # snippet = "\n".join(new_value.split("\n")[start_line : end_line + 1])

    # Prepare the success message
    success_msg = f"The core memory block with label `{label}` has been edited. "
    # success_msg += self._make_output(
    #     snippet, f"a snippet of {path}", start_line + 1
    # )
    # success_msg += f"A snippet of core memory block `{label}`:\n{snippet}\n"
    success_msg += "Review the changes and make sure they are as expected (correct indentation, no duplicate lines, etc). Edit the memory block again if necessary."

    # return None
    return success_msg


def memory_insert(agent_state: "AgentState", label: str, new_str: str, insert_line: int = -1) -> Optional[str]:  # type: ignore
    """
    The memory_insert command allows you to insert text at a specific location in a memory block.

    Args:
        label (str): Section of the memory to be edited, identified by its label.
        new_str (str): The text to insert. Do not include line number prefixes.
        insert_line (int): The line number after which to insert the text (0 for beginning of file). Defaults to -1 (end of the file).

    Examples:
        # Update a block containing information about the user (append to the end of the block)
        memory_insert(label="customer", new_str="The customer's ticket number is 12345")

        # Update a block containing information about the user (insert at the beginning of the block)
        memory_insert(label="customer", new_str="The customer's ticket number is 12345", insert_line=0)

    Returns:
        Optional[str]: None is always returned as this function does not produce a response.
    """
    import re

    if bool(re.search(r"\nLine \d+: ", new_str)):
        raise ValueError(
            "new_str contains a line number prefix, which is not allowed. Do not include line numbers when calling memory tools (line numbers are for display purposes only)."
        )
    if CORE_MEMORY_LINE_NUMBER_WARNING in new_str:
        raise ValueError(
            "new_str contains a line number warning, which is not allowed. Do not include line number information when calling memory tools (line numbers are for display purposes only)."
        )

    current_value = str(agent_state.memory.get_block(label).value).expandtabs()
    new_str = str(new_str).expandtabs()
    current_value_lines = current_value.split("\n")
    n_lines = len(current_value_lines)

    # Check if we're in range, from 0 (pre-line), to 1 (first line), to n_lines (last line)
    if insert_line == -1:
        insert_line = n_lines
    elif insert_line < 0 or insert_line > n_lines:
        raise ValueError(
            f"Invalid `insert_line` parameter: {insert_line}. It should be within the range of lines of the memory block: {[0, n_lines]}, or -1 to append to the end of the memory block."
        )

    # Insert the new string as a line
    new_str_lines = new_str.split("\n")
    new_value_lines = current_value_lines[:insert_line] + new_str_lines + current_value_lines[insert_line:]
    snippet_lines = (
        current_value_lines[max(0, insert_line - SNIPPET_LINES) : insert_line]
        + new_str_lines
        + current_value_lines[insert_line : insert_line + SNIPPET_LINES]
    )

    # Collate into the new value to update
    new_value = "\n".join(new_value_lines)
    # snippet = "\n".join(snippet_lines)

    # Write into the block
    agent_state.memory.update_block_value(label=label, value=new_value)

    # Prepare the success message
    success_msg = f"The core memory block with label `{label}` has been edited. "
    # success_msg += self._make_output(
    #     snippet,
    #     "a snippet of the edited file",
    #     max(1, insert_line - SNIPPET_LINES + 1),
    # )
    # success_msg += f"A snippet of core memory block `{label}`:\n{snippet}\n"
    success_msg += "Review the changes and make sure they are as expected (correct indentation, no duplicate lines, etc). Edit the memory block again if necessary."

    return success_msg


def memory_rethink(agent_state: "AgentState", label: str, new_memory: str) -> None:
    """
    The memory_rethink command allows you to completely rewrite the contents of a memory block. Use this tool to make large sweeping changes (e.g. when you want to condense or reorganize the memory blocks), do NOT use this tool to make small precise edits (e.g. add or remove a line, replace a specific string, etc).

    Args:
        label (str): The memory block to be rewritten, identified by its label.
        new_memory (str): The new memory contents with information integrated from existing memory blocks and the conversation context.

    Returns:
        None: None is always returned as this function does not produce a response.
    """
    import re

    if bool(re.search(r"\nLine \d+: ", new_memory)):
        raise ValueError(
            "new_memory contains a line number prefix, which is not allowed. Do not include line numbers when calling memory tools (line numbers are for display purposes only)."
        )
    if CORE_MEMORY_LINE_NUMBER_WARNING in new_memory:
        raise ValueError(
            "new_memory contains a line number warning, which is not allowed. Do not include line number information when calling memory tools (line numbers are for display purposes only)."
        )

    if agent_state.memory.get_block(label) is None:
        agent_state.memory.create_block(label=label, value=new_memory)

    agent_state.memory.update_block_value(label=label, value=new_memory)

    # Prepare the success message
    success_msg = f"The core memory block with label `{label}` has been edited. "
    # success_msg += self._make_output(
    #     snippet, f"a snippet of {path}", start_line + 1
    # )
    # success_msg += f"A snippet of core memory block `{label}`:\n{snippet}\n"
    success_msg += "Review the changes and make sure they are as expected (correct indentation, no duplicate lines, etc). Edit the memory block again if necessary."

    # return None
    return success_msg


def memory_finish_edits(agent_state: "AgentState") -> None:  # type: ignore
    """
    Call the memory_finish_edits command when you are finished making edits (integrating all new information) into the memory blocks. This function is called when the agent is done rethinking the memory.

    Returns:
        Optional[str]: None is always returned as this function does not produce a response.
    """
    return None