diff --git a/scripts/token_counter.py b/scripts/token_counter.py new file mode 100644 index 00000000..a28a9868 --- /dev/null +++ b/scripts/token_counter.py @@ -0,0 +1,57 @@ +import tiktoken +from typing import List, Dict + +def count_message_tokens(messages : List[Dict[str, str]], model : str = "gpt-3.5-turbo-0301") -> int: + """ + Returns the number of tokens used by a list of messages. + + Args: + messages (list): A list of messages, each of which is a dictionary containing the role and content of the message. + model (str): The name of the model to use for tokenization. Defaults to "gpt-3.5-turbo-0301". + + Returns: + int: The number of tokens used by the list of messages. + """ + try: + encoding = tiktoken.encoding_for_model(model) + except KeyError: + print("Warning: model not found. Using cl100k_base encoding.") + encoding = tiktoken.get_encoding("cl100k_base") + if model == "gpt-3.5-turbo": + # !Node: gpt-3.5-turbo may change over time. Returning num tokens assuming gpt-3.5-turbo-0301.") + return count_message_tokens(messages, model="gpt-3.5-turbo-0301") + elif model == "gpt-4": + # !Note: gpt-4 may change over time. Returning num tokens assuming gpt-4-0314.") + return count_message_tokens(messages, model="gpt-4-0314") + elif model == "gpt-3.5-turbo-0301": + tokens_per_message = 4 # every message follows <|start|>{role/name}\n{content}<|end|>\n + tokens_per_name = -1 # if there's a name, the role is omitted + elif model == "gpt-4-0314": + tokens_per_message = 3 + tokens_per_name = 1 + else: + raise NotImplementedError(f"""num_tokens_from_messages() is not implemented for model {model}. See https://github.com/openai/openai-python/blob/main/chatml.md for information on how messages are converted to tokens.""") + num_tokens = 0 + for message in messages: + num_tokens += tokens_per_message + for key, value in message.items(): + num_tokens += len(encoding.encode(value)) + if key == "name": + num_tokens += tokens_per_name + num_tokens += 3 # every reply is primed with <|start|>assistant<|message|> + return num_tokens + +def count_string_tokens(string: str, model_name: str) -> int: + """ + Returns the number of tokens in a text string. + + Args: + string (str): The text string. + model_name (str): The name of the encoding to use. (e.g., "gpt-3.5-turbo") + + Returns: + int: The number of tokens in the text string. + """ + encoding = tiktoken.encoding_for_model(model_name) + num_tokens = len(encoding.encode(string)) + return num_tokens