messages

Messages are objects used in prompts and chat conversations.

Class hierarchy:

BaseMessage --> SystemMessage, AIMessage, HumanMessage, ChatMessage, FunctionMessage, ToolMessage --> BaseMessageChunk --> SystemMessageChunk, AIMessageChunk, HumanMessageChunk, ChatMessageChunk, FunctionMessageChunk, ToolMessageChunk 

Main helpers:

ChatPromptTemplate 

Classes

messages.ai.AIMessage	Message from an AI.
messages.ai.AIMessageChunk	Message chunk from an AI.
messages.ai.InputTokenDetails	Breakdown of input token counts.
messages.ai.OutputTokenDetails	Breakdown of output token counts.
messages.ai.UsageMetadata	Usage metadata for a message, such as token counts.
messages.base.BaseMessage	Base abstract message class.
messages.base.BaseMessageChunk	Message chunk, which can be concatenated with other Message chunks.
messages.chat.ChatMessage	Message that can be assigned an arbitrary speaker (i.e. role).
messages.chat.ChatMessageChunk	Chat Message chunk.
messages.content_blocks.Base64ContentBlock	Content block for inline data from a base64 string.
messages.content_blocks.BaseDataContentBlock	Base class for data content blocks.
messages.content_blocks.IDContentBlock	Content block for data specified by an identifier.
messages.content_blocks.PlainTextContentBlock	Content block for plain text data (e.g., from a document).
messages.content_blocks.URLContentBlock	Content block for data from a URL.
messages.function.FunctionMessage	Message for passing the result of executing a tool back to a model.
messages.function.FunctionMessageChunk	Function Message chunk.
messages.human.HumanMessage	Message from a human.
messages.human.HumanMessageChunk	Human Message chunk.
messages.modifier.RemoveMessage	Message responsible for deleting other messages.
messages.system.SystemMessage	Message for priming AI behavior.
messages.system.SystemMessageChunk	System Message chunk.
messages.tool.InvalidToolCall	Allowance for errors made by LLM.
messages.tool.ToolCall	Represents a request to call a tool.
messages.tool.ToolCallChunk	A chunk of a tool call (e.g., as part of a stream).
messages.tool.ToolMessage	Message for passing the result of executing a tool back to a model.
messages.tool.ToolMessageChunk	Tool Message chunk.
messages.tool.ToolOutputMixin()	Mixin for objects that tools can return directly.

Functions

messages.ai.add_ai_message_chunks(left, *others)	Add multiple AIMessageChunks together.
messages.ai.add_usage(left, right)	Recursively add two UsageMetadata objects.
messages.ai.subtract_usage(left, right)	Recursively subtract two UsageMetadata objects.
messages.base.get_msg_title_repr(title, *[, ...])	Get a title representation for a message.
messages.base.merge_content(first_content, ...)	Merge multiple message contents.
messages.base.message_to_dict(message)	Convert a Message to a dictionary.
messages.base.messages_to_dict(messages)	Convert a sequence of Messages to a list of dictionaries.
messages.content_blocks.convert_to_openai_data_block(block)	Format standard data content block to format expected by OpenAI.
messages.content_blocks.convert_to_openai_image_block(...)	Convert image content block to format expected by OpenAI Chat Completions API.
messages.content_blocks.is_data_content_block(...)	Check if the content block is a standard data content block.
messages.tool.default_tool_chunk_parser(...)	Best-effort parsing of tool chunks.
messages.tool.default_tool_parser(raw_tool_calls)	Best-effort parsing of tools.
messages.tool.invalid_tool_call(*[, name, ...])	Create an invalid tool call.
messages.tool.tool_call(*, name, args, id)	Create a tool call.
messages.tool.tool_call_chunk(*[, name, ...])	Create a tool call chunk.
messages.utils.convert_to_messages(messages)	Convert a sequence of messages to a list of messages.
messages.utils.convert_to_openai_messages(...)	Convert LangChain messages into OpenAI message dicts.
messages.utils.count_tokens_approximately(...)	Approximate the total number of tokens in messages.
messages.utils.filter_messages([messages])	Filter messages based on name, type or id.
messages.utils.get_buffer_string(messages[, ...])	Convert a sequence of Messages to strings and concatenate them into one string.
messages.utils.merge_message_runs([messages])	Merge consecutive Messages of the same type.
messages.utils.message_chunk_to_message(chunk)	Convert a message chunk to a message.
messages.utils.messages_from_dict(messages)	Convert a sequence of messages from dicts to Message objects.
messages.utils.trim_messages([messages])	Trim messages to be below a token count.