"""Callback Handler that prints to std out."""
import threading
from enum import Enum, auto
from typing import Any, Dict, List
from langchain_core._api import warn_deprecated
from langchain_core.callbacks import BaseCallbackHandler
from langchain_core.messages import AIMessage
from langchain_core.outputs import ChatGeneration, LLMResult
MODEL_COST_PER_1K_TOKENS = {
# GPT-4.1 input
"gpt-4.1": 0.002,
"gpt-4.1-2025-04-14": 0.002,
"gpt-4.1-cached": 0.0005,
"gpt-4.1-2025-04-14-cached": 0.0005,
# GPT-4.1 output
"gpt-4.1-completion": 0.008,
"gpt-4.1-2025-04-14-completion": 0.008,
# GPT-4.1-mini input
"gpt-4.1-mini": 0.0004,
"gpt-4.1-mini-2025-04-14": 0.0004,
"gpt-4.1-mini-cached": 0.0001,
"gpt-4.1-mini-2025-04-14-cached": 0.0001,
# GPT-4.1-mini output
"gpt-4.1-mini-completion": 0.0016,
"gpt-4.1-mini-2025-04-14-completion": 0.0016,
# GPT-4.1-nano input
"gpt-4.1-nano": 0.0001,
"gpt-4.1-nano-2025-04-14": 0.0001,
"gpt-4.1-nano-cached": 0.000025,
"gpt-4.1-nano-2025-04-14-cached": 0.000025,
# GPT-4.1-nano output
"gpt-4.1-nano-completion": 0.0004,
"gpt-4.1-nano-2025-04-14-completion": 0.0004,
# GPT-4.5-preview input
"gpt-4.5-preview": 0.075,
"gpt-4.5-preview-2025-02-27": 0.075,
"gpt-4.5-preview-cached": 0.0375,
"gpt-4.5-preview-2025-02-27-cached": 0.0375,
# GPT-4.5-preview output
"gpt-4.5-preview-completion": 0.15,
"gpt-4.5-preview-2025-02-27-completion": 0.15,
# OpenAI o1 input
"o1": 0.015,
"o1-2024-12-17": 0.015,
"o1-cached": 0.0075,
"o1-2024-12-17-cached": 0.0075,
# OpenAI o1 output
"o1-completion": 0.06,
"o1-2024-12-17-completion": 0.06,
# OpenAI o1-pro input
"o1-pro": 0.15,
"o1-pro-2025-03-19": 0.15,
# OpenAI o1-pro output
"o1-pro-completion": 0.6,
"o1-pro-2025-03-19-completion": 0.6,
# OpenAI o3 input
"o3": 0.01,
"o3-2025-04-16": 0.01,
"o3-cached": 0.0025,
"o3-2025-04-16-cached": 0.0025,
# OpenAI o3 output
"o3-completion": 0.04,
"o3-2025-04-16-completion": 0.04,
# OpenAI o4-mini input
"o4-mini": 0.0011,
"o4-mini-2025-04-16": 0.0011,
"o4-mini-cached": 0.000275,
"o4-mini-2025-04-16-cached": 0.000275,
# OpenAI o4-mini output
"o4-mini-completion": 0.0044,
"o4-mini-2025-04-16-completion": 0.0044,
# OpenAI o3-mini input
"o3-mini": 0.0011,
"o3-mini-2025-01-31": 0.0011,
"o3-mini-cached": 0.00055,
"o3-mini-2025-01-31-cached": 0.00055,
# OpenAI o3-mini output
"o3-mini-completion": 0.0044,
"o3-mini-2025-01-31-completion": 0.0044,
# OpenAI o1-mini input (updated pricing)
"o1-mini": 0.0011,
"o1-mini-cached": 0.00055,
"o1-mini-2024-09-12": 0.0011,
"o1-mini-2024-09-12-cached": 0.00055,
# OpenAI o1-mini output (updated pricing)
"o1-mini-completion": 0.0044,
"o1-mini-2024-09-12-completion": 0.0044,
# OpenAI o1-preview input
"o1-preview": 0.015,
"o1-preview-cached": 0.0075,
"o1-preview-2024-09-12": 0.015,
"o1-preview-2024-09-12-cached": 0.0075,
# OpenAI o1-preview output
"o1-preview-completion": 0.06,
"o1-preview-2024-09-12-completion": 0.06,
# GPT-4o input
"gpt-4o": 0.0025,
"gpt-4o-cached": 0.00125,
"gpt-4o-2024-05-13": 0.005,
"gpt-4o-2024-08-06": 0.0025,
"gpt-4o-2024-08-06-cached": 0.00125,
"gpt-4o-2024-11-20": 0.0025,
"gpt-4o-2024-11-20-cached": 0.00125,
# GPT-4o output
"gpt-4o-completion": 0.01,
"gpt-4o-2024-05-13-completion": 0.015,
"gpt-4o-2024-08-06-completion": 0.01,
"gpt-4o-2024-11-20-completion": 0.01,
# GPT-4o-audio-preview input
"gpt-4o-audio-preview": 0.0025,
"gpt-4o-audio-preview-2024-12-17": 0.0025,
"gpt-4o-audio-preview-2024-10-01": 0.0025,
# GPT-4o-audio-preview output
"gpt-4o-audio-preview-completion": 0.01,
"gpt-4o-audio-preview-2024-12-17-completion": 0.01,
"gpt-4o-audio-preview-2024-10-01-completion": 0.01,
# GPT-4o-realtime-preview input
"gpt-4o-realtime-preview": 0.005,
"gpt-4o-realtime-preview-2024-12-17": 0.005,
"gpt-4o-realtime-preview-2024-10-01": 0.005,
"gpt-4o-realtime-preview-cached": 0.0025,
"gpt-4o-realtime-preview-2024-12-17-cached": 0.0025,
"gpt-4o-realtime-preview-2024-10-01-cached": 0.0025,
# GPT-4o-realtime-preview output
"gpt-4o-realtime-preview-completion": 0.02,
"gpt-4o-realtime-preview-2024-12-17-completion": 0.02,
"gpt-4o-realtime-preview-2024-10-01-completion": 0.02,
# GPT-4o-mini input
"gpt-4o-mini": 0.00015,
"gpt-4o-mini-cached": 0.000075,
"gpt-4o-mini-2024-07-18": 0.00015,
"gpt-4o-mini-2024-07-18-cached": 0.000075,
# GPT-4o-mini output
"gpt-4o-mini-completion": 0.0006,
"gpt-4o-mini-2024-07-18-completion": 0.0006,
# GPT-4o-mini-audio-preview input
"gpt-4o-mini-audio-preview": 0.00015,
"gpt-4o-mini-audio-preview-2024-12-17": 0.00015,
# GPT-4o-mini-audio-preview output
"gpt-4o-mini-audio-preview-completion": 0.0006,
"gpt-4o-mini-audio-preview-2024-12-17-completion": 0.0006,
# GPT-4o-mini-realtime-preview input
"gpt-4o-mini-realtime-preview": 0.0006,
"gpt-4o-mini-realtime-preview-2024-12-17": 0.0006,
"gpt-4o-mini-realtime-preview-cached": 0.0003,
"gpt-4o-mini-realtime-preview-2024-12-17-cached": 0.0003,
# GPT-4o-mini-realtime-preview output
"gpt-4o-mini-realtime-preview-completion": 0.0024,
"gpt-4o-mini-realtime-preview-2024-12-17-completion": 0.0024,
# GPT-4o-mini-search-preview input
"gpt-4o-mini-search-preview": 0.00015,
"gpt-4o-mini-search-preview-2025-03-11": 0.00015,
# GPT-4o-mini-search-preview output
"gpt-4o-mini-search-preview-completion": 0.0006,
"gpt-4o-mini-search-preview-2025-03-11-completion": 0.0006,
# GPT-4o-search-preview input
"gpt-4o-search-preview": 0.0025,
"gpt-4o-search-preview-2025-03-11": 0.0025,
# GPT-4o-search-preview output
"gpt-4o-search-preview-completion": 0.01,
"gpt-4o-search-preview-2025-03-11-completion": 0.01,
# Computer-use-preview input
"computer-use-preview": 0.003,
"computer-use-preview-2025-03-11": 0.003,
# Computer-use-preview output
"computer-use-preview-completion": 0.012,
"computer-use-preview-2025-03-11-completion": 0.012,
# GPT-4 input
"gpt-4": 0.03,
"gpt-4-0314": 0.03,
"gpt-4-0613": 0.03,
"gpt-4-32k": 0.06,
"gpt-4-32k-0314": 0.06,
"gpt-4-32k-0613": 0.06,
"gpt-4-vision-preview": 0.01,
"gpt-4-1106-preview": 0.01,
"gpt-4-0125-preview": 0.01,
"gpt-4-turbo-preview": 0.01,
"gpt-4-turbo": 0.01,
"gpt-4-turbo-2024-04-09": 0.01,
# GPT-4 output
"gpt-4-completion": 0.06,
"gpt-4-0314-completion": 0.06,
"gpt-4-0613-completion": 0.06,
"gpt-4-32k-completion": 0.12,
"gpt-4-32k-0314-completion": 0.12,
"gpt-4-32k-0613-completion": 0.12,
"gpt-4-vision-preview-completion": 0.03,
"gpt-4-1106-preview-completion": 0.03,
"gpt-4-0125-preview-completion": 0.03,
"gpt-4-turbo-preview-completion": 0.03,
"gpt-4-turbo-completion": 0.03,
"gpt-4-turbo-2024-04-09-completion": 0.03,
# GPT-3.5 input
# gpt-3.5-turbo points at gpt-3.5-turbo-0613 until Feb 16, 2024.
# Switches to gpt-3.5-turbo-0125 after.
"gpt-3.5-turbo": 0.0015,
"gpt-3.5-turbo-0125": 0.0005,
"gpt-3.5-turbo-0301": 0.0015,
"gpt-3.5-turbo-0613": 0.0015,
"gpt-3.5-turbo-1106": 0.001,
"gpt-3.5-turbo-instruct": 0.0015,
"gpt-3.5-turbo-16k": 0.003,
"gpt-3.5-turbo-16k-0613": 0.003,
# GPT-3.5 output
# gpt-3.5-turbo points at gpt-3.5-turbo-0613 until Feb 16, 2024.
# Switches to gpt-3.5-turbo-0125 after.
"gpt-3.5-turbo-completion": 0.002,
"gpt-3.5-turbo-0125-completion": 0.0015,
"gpt-3.5-turbo-0301-completion": 0.002,
"gpt-3.5-turbo-0613-completion": 0.002,
"gpt-3.5-turbo-1106-completion": 0.002,
"gpt-3.5-turbo-instruct-completion": 0.002,
"gpt-3.5-turbo-16k-completion": 0.004,
"gpt-3.5-turbo-16k-0613-completion": 0.004,
# Azure GPT-35 input
"gpt-35-turbo": 0.0015, # Azure OpenAI version of ChatGPT
"gpt-35-turbo-0125": 0.0005,
"gpt-35-turbo-0301": 0.002, # Azure OpenAI version of ChatGPT
"gpt-35-turbo-0613": 0.0015,
"gpt-35-turbo-instruct": 0.0015,
"gpt-35-turbo-16k": 0.003,
"gpt-35-turbo-16k-0613": 0.003,
# Azure GPT-35 output
"gpt-35-turbo-completion": 0.002, # Azure OpenAI version of ChatGPT
"gpt-35-turbo-0125-completion": 0.0015,
"gpt-35-turbo-0301-completion": 0.002, # Azure OpenAI version of ChatGPT
"gpt-35-turbo-0613-completion": 0.002,
"gpt-35-turbo-instruct-completion": 0.002,
"gpt-35-turbo-16k-completion": 0.004,
"gpt-35-turbo-16k-0613-completion": 0.004,
# Others
"text-ada-001": 0.0004,
"ada": 0.0004,
"text-babbage-001": 0.0005,
"babbage": 0.0005,
"text-curie-001": 0.002,
"curie": 0.002,
"text-davinci-003": 0.02,
"text-davinci-002": 0.02,
"code-davinci-002": 0.02,
# Fine Tuned input
"babbage-002-finetuned": 0.0016,
"davinci-002-finetuned": 0.012,
"gpt-3.5-turbo-0613-finetuned": 0.003,
"gpt-3.5-turbo-1106-finetuned": 0.003,
"gpt-3.5-turbo-0125-finetuned": 0.003,
"gpt-4o-mini-2024-07-18-finetuned": 0.0003,
"gpt-4o-mini-2024-07-18-finetuned-cached": 0.00015,
# Fine Tuned output
"babbage-002-finetuned-completion": 0.0016,
"davinci-002-finetuned-completion": 0.012,
"gpt-3.5-turbo-0613-finetuned-completion": 0.006,
"gpt-3.5-turbo-1106-finetuned-completion": 0.006,
"gpt-3.5-turbo-0125-finetuned-completion": 0.006,
"gpt-4o-mini-2024-07-18-finetuned-completion": 0.0012,
# Azure Fine Tuned input
"babbage-002-azure-finetuned": 0.0004,
"davinci-002-azure-finetuned": 0.002,
"gpt-35-turbo-0613-azure-finetuned": 0.0015,
# Azure Fine Tuned output
"babbage-002-azure-finetuned-completion": 0.0004,
"davinci-002-azure-finetuned-completion": 0.002,
"gpt-35-turbo-0613-azure-finetuned-completion": 0.002,
# Legacy fine-tuned models
"ada-finetuned-legacy": 0.0016,
"babbage-finetuned-legacy": 0.0024,
"curie-finetuned-legacy": 0.012,
"davinci-finetuned-legacy": 0.12,
}
[docs]
class TokenType(Enum):
"""Token type enum."""
PROMPT = auto()
PROMPT_CACHED = auto()
COMPLETION = auto()
[docs]
def standardize_model_name(
model_name: str,
is_completion: bool = False,
*,
token_type: TokenType = TokenType.PROMPT,
) -> str:
"""
Standardize the model name to a format that can be used in the OpenAI API.
Args:
model_name: Model name to standardize.
is_completion: Whether the model is used for completion or not.
Defaults to False. Deprecated in favor of ``token_type``.
token_type: Token type. Defaults to ``TokenType.PROMPT``.
Returns:
Standardized model name.
"""
if is_completion:
warn_deprecated(
since="0.3.13",
message=(
"is_completion is deprecated. Use token_type instead. Example:\n\n"
"from langchain_community.callbacks.openai_info import TokenType\n\n"
"standardize_model_name('gpt-4o', token_type=TokenType.COMPLETION)\n"
),
removal="1.0",
)
token_type = TokenType.COMPLETION
model_name = model_name.lower()
if ".ft-" in model_name:
model_name = model_name.split(".ft-")[0] + "-azure-finetuned"
if ":ft-" in model_name:
model_name = model_name.split(":")[0] + "-finetuned-legacy"
if "ft:" in model_name:
model_name = model_name.split(":")[1] + "-finetuned"
if token_type == TokenType.COMPLETION and (
model_name.startswith("gpt-4")
or model_name.startswith("gpt-3.5")
or model_name.startswith("gpt-35")
or model_name.startswith("o1-")
or model_name.startswith("o3-")
or model_name.startswith("o4-")
or ("finetuned" in model_name and "legacy" not in model_name)
):
return model_name + "-completion"
if (
token_type == TokenType.PROMPT_CACHED
and (
model_name.startswith("gpt-4o")
or model_name.startswith("gpt-4.1")
or model_name.startswith("o1")
or model_name.startswith("o3")
or model_name.startswith("o4")
)
and not (model_name.startswith("gpt-4o-2024-05-13"))
):
return model_name + "-cached"
else:
return model_name
[docs]
def get_openai_token_cost_for_model(
model_name: str,
num_tokens: int,
is_completion: bool = False,
*,
token_type: TokenType = TokenType.PROMPT,
) -> float:
"""
Get the cost in USD for a given model and number of tokens.
Args:
model_name: Name of the model
num_tokens: Number of tokens.
is_completion: Whether the model is used for completion or not.
Defaults to False. Deprecated in favor of ``token_type``.
token_type: Token type. Defaults to ``TokenType.PROMPT``.
Returns:
Cost in USD.
"""
if is_completion:
warn_deprecated(
since="0.3.13",
message=(
"is_completion is deprecated. Use token_type instead. Example:\n\n"
"from langchain_community.callbacks.openai_info import TokenType\n\n"
"get_openai_token_cost_for_model('gpt-4o', 10, token_type=TokenType.COMPLETION)\n" # noqa: E501
),
removal="1.0",
)
token_type = TokenType.COMPLETION
model_name = standardize_model_name(model_name, token_type=token_type)
if model_name not in MODEL_COST_PER_1K_TOKENS:
raise ValueError(
f"Unknown model: {model_name}. Please provide a valid OpenAI model name."
"Known models are: " + ", ".join(MODEL_COST_PER_1K_TOKENS.keys())
)
return MODEL_COST_PER_1K_TOKENS[model_name] * (num_tokens / 1000)
[docs]
class OpenAICallbackHandler(BaseCallbackHandler):
"""Callback Handler that tracks OpenAI info."""
total_tokens: int = 0
prompt_tokens: int = 0
prompt_tokens_cached: int = 0
completion_tokens: int = 0
reasoning_tokens: int = 0
successful_requests: int = 0
total_cost: float = 0.0
[docs]
def __init__(self) -> None:
super().__init__()
self._lock = threading.Lock()
def __repr__(self) -> str:
return (
f"Tokens Used: {self.total_tokens}\n"
f"\tPrompt Tokens: {self.prompt_tokens}\n"
f"\t\tPrompt Tokens Cached: {self.prompt_tokens_cached}\n"
f"\tCompletion Tokens: {self.completion_tokens}\n"
f"\t\tReasoning Tokens: {self.reasoning_tokens}\n"
f"Successful Requests: {self.successful_requests}\n"
f"Total Cost (USD): ${self.total_cost}"
)
@property
def always_verbose(self) -> bool:
"""Whether to call verbose callbacks even if verbose is False."""
return True
[docs]
def on_llm_start(
self, serialized: Dict[str, Any], prompts: List[str], **kwargs: Any
) -> None:
"""Print out the prompts."""
pass
[docs]
def on_llm_new_token(self, token: str, **kwargs: Any) -> None:
"""Print out the token."""
pass
[docs]
def on_llm_end(self, response: LLMResult, **kwargs: Any) -> None:
"""Collect token usage."""
# Check for usage_metadata (langchain-core >= 0.2.2)
try:
generation = response.generations[0][0]
except IndexError:
generation = None
if isinstance(generation, ChatGeneration):
try:
message = generation.message
if isinstance(message, AIMessage):
usage_metadata = message.usage_metadata
response_metadata = message.response_metadata
else:
usage_metadata = None
response_metadata = None
except AttributeError:
usage_metadata = None
response_metadata = None
else:
usage_metadata = None
response_metadata = None
prompt_tokens_cached = 0
reasoning_tokens = 0
if usage_metadata:
token_usage = {"total_tokens": usage_metadata["total_tokens"]}
completion_tokens = usage_metadata["output_tokens"]
prompt_tokens = usage_metadata["input_tokens"]
if response_model_name := (response_metadata or {}).get("model_name"):
model_name = standardize_model_name(response_model_name)
elif response.llm_output is None:
model_name = ""
else:
model_name = standardize_model_name(
response.llm_output.get("model_name", "")
)
if "cache_read" in usage_metadata.get("input_token_details", {}):
prompt_tokens_cached = usage_metadata["input_token_details"][
"cache_read"
]
if "reasoning" in usage_metadata.get("output_token_details", {}):
reasoning_tokens = usage_metadata["output_token_details"]["reasoning"]
else:
if response.llm_output is None:
return None
if "token_usage" not in response.llm_output:
with self._lock:
self.successful_requests += 1
return None
# compute tokens and cost for this request
token_usage = response.llm_output["token_usage"]
completion_tokens = token_usage.get("completion_tokens", 0)
prompt_tokens = token_usage.get("prompt_tokens", 0)
model_name = standardize_model_name(
response.llm_output.get("model_name", "")
)
if model_name in MODEL_COST_PER_1K_TOKENS:
uncached_prompt_tokens = prompt_tokens - prompt_tokens_cached
uncached_prompt_cost = get_openai_token_cost_for_model(
model_name, uncached_prompt_tokens, token_type=TokenType.PROMPT
)
cached_prompt_cost = get_openai_token_cost_for_model(
model_name, prompt_tokens_cached, token_type=TokenType.PROMPT_CACHED
)
prompt_cost = uncached_prompt_cost + cached_prompt_cost
completion_cost = get_openai_token_cost_for_model(
model_name, completion_tokens, token_type=TokenType.COMPLETION
)
else:
completion_cost = 0
prompt_cost = 0
# update shared state behind lock
with self._lock:
self.total_cost += prompt_cost + completion_cost
self.total_tokens += token_usage.get("total_tokens", 0)
self.prompt_tokens += prompt_tokens
self.prompt_tokens_cached += prompt_tokens_cached
self.completion_tokens += completion_tokens
self.reasoning_tokens += reasoning_tokens
self.successful_requests += 1
def __copy__(self) -> "OpenAICallbackHandler":
"""Return a copy of the callback handler."""
return self
def __deepcopy__(self, memo: Any) -> "OpenAICallbackHandler":
"""Return a deep copy of the callback handler."""
return self
