LangSmith utilities¶
langchain-classic documentation
These docs cover the langchain-classic package. This package will be maintained for security vulnerabilities until December 2026. Users are encouraged to migrate to the langchain package for the latest features and improvements. See docs for langchain
langchain_classic.smith
¶
LangSmith utilities.
This module provides utilities for connecting to LangSmith.
Evaluation
LangSmith helps you evaluate Chains and other language model application components
using a number of LangChain evaluators.
An example of this is shown below, assuming you've created a LangSmith dataset
called <my_dataset_name>:
from langsmith import Client
from langchain_openai import ChatOpenAI
from langchain_classic.chains import LLMChain
from langchain_classic.smith import RunEvalConfig, run_on_dataset
# Chains may have memory. Passing in a constructor function lets the
# evaluation framework avoid cross-contamination between runs.
def construct_chain():
model = ChatOpenAI(temperature=0)
chain = LLMChain.from_string(model, "What's the answer to {your_input_key}")
return chain
# Load off-the-shelf evaluators via config or the EvaluatorType (string or enum)
evaluation_config = RunEvalConfig(
evaluators=[
"qa", # "Correctness" against a reference answer
"embedding_distance",
RunEvalConfig.Criteria("helpfulness"),
RunEvalConfig.Criteria(
{
"fifth-grader-score": "Do you have to be smarter than a fifth "
"grader to answer this question?"
}
),
]
)
client = Client()
run_on_dataset(
client,
"<my_dataset_name>",
construct_chain,
evaluation=evaluation_config,
)
You can also create custom evaluators by subclassing the
StringEvaluator <langchain.evaluation.schema.StringEvaluator>
or LangSmith's RunEvaluator classes.
from typing import Optional
from langchain_classic.evaluation import StringEvaluator
class MyStringEvaluator(StringEvaluator):
@property
def requires_input(self) -> bool:
return False
@property
def requires_reference(self) -> bool:
return True
@property
def evaluation_name(self) -> str:
return "exact_match"
def _evaluate_strings(
self, prediction, reference=None, input=None, **kwargs
) -> dict:
return {"score": prediction == reference}
evaluation_config = RunEvalConfig(
custom_evaluators=[MyStringEvaluator()],
)
run_on_dataset(
client,
"<my_dataset_name>",
construct_chain,
evaluation=evaluation_config,
)
Primary Functions
arun_on_dataset <langchain.smith.evaluation.runner_utils.arun_on_dataset>: Asynchronous function to evaluate a chain, agent, or other LangChain component over a dataset.run_on_dataset <langchain.smith.evaluation.runner_utils.run_on_dataset>: Function to evaluate a chain, agent, or other LangChain component over a dataset.RunEvalConfig <langchain.smith.evaluation.config.RunEvalConfig>: Class representing the configuration for running evaluation. You can select evaluators byEvaluatorType <langchain.evaluation.schema.EvaluatorType>or config, or you can pass incustom_evaluators.
| FUNCTION | DESCRIPTION |
|---|---|
arun_on_dataset |
Run on dataset. |
run_on_dataset |
Run on dataset. |
RunEvalConfig
¶
Bases: BaseModel
Configuration for a run evaluation.
evaluators
class-attribute
instance-attribute
¶
Configurations for which evaluators to apply to the dataset run.
Each can be the string of an
EvaluatorType <langchain.evaluation.schema.EvaluatorType>, such
as EvaluatorType.QA, the evaluator type string ("qa"), or a configuration for a
given evaluator
(e.g.,
RunEvalConfig.QA <langchain.smith.evaluation.config.RunEvalConfig.QA>).
custom_evaluators
class-attribute
instance-attribute
¶
custom_evaluators: list[CUSTOM_EVALUATOR_TYPE] | None = None
Custom evaluators to apply to the dataset run.
batch_evaluators
class-attribute
instance-attribute
¶
batch_evaluators: list[BATCH_EVALUATOR_LIKE] | None = None
Evaluators that run on an aggregate/batch level.
These generate one or more metrics that are assigned to the full test run. As a result, they are not associated with individual traces.
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
input_key
class-attribute
instance-attribute
¶
input_key: str | None = None
The key from the traced run's inputs dictionary to use to represent the input. If not provided, it will be inferred automatically.
eval_llm
class-attribute
instance-attribute
¶
eval_llm: BaseLanguageModel | None = None
The language model to pass to any evaluators that require one.
Criteria
¶
Bases: SingleKeyEvalConfig
Configuration for a reference-free criteria evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
criteria |
The criteria to evaluate.
TYPE:
|
llm |
The language model to use for the evaluation chain.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
LabeledCriteria
¶
Bases: SingleKeyEvalConfig
Configuration for a labeled (with references) criteria evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
criteria |
The criteria to evaluate.
TYPE:
|
llm |
The language model to use for the evaluation chain.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
EmbeddingDistance
¶
Bases: SingleKeyEvalConfig
Configuration for an embedding distance evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
embeddings |
The embeddings to use for computing the distance.
TYPE:
|
distance_metric |
The distance metric to use for computing the distance.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
StringDistance
¶
Bases: SingleKeyEvalConfig
Configuration for a string distance evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
distance |
The string distance metric to use (
TYPE:
|
normalize_score |
Whether to normalize the distance to between 0 and 1. Applies only to the Levenshtein and Damerau-Levenshtein distances.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
QA
¶
Bases: SingleKeyEvalConfig
Configuration for a QA evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
prompt |
The prompt template to use for generating the question.
TYPE:
|
llm |
The language model to use for the evaluation chain.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
ContextQA
¶
Bases: SingleKeyEvalConfig
Configuration for a context-based QA evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
prompt |
The prompt template to use for generating the question.
TYPE:
|
llm |
The language model to use for the evaluation chain.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
CoTQA
¶
Bases: SingleKeyEvalConfig
Configuration for a context-based QA evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
prompt |
The prompt template to use for generating the question.
TYPE:
|
llm |
The language model to use for the evaluation chain.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
JsonValidity
¶
Bases: SingleKeyEvalConfig
Configuration for a json validity evaluator.
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
JsonEqualityEvaluator
¶
Bases: EvalConfig
Configuration for a json equality evaluator.
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
ExactMatch
¶
Bases: SingleKeyEvalConfig
Configuration for an exact match string evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
ignore_case |
Whether to ignore case when comparing strings.
TYPE:
|
ignore_punctuation |
Whether to ignore punctuation when comparing strings.
TYPE:
|
ignore_numbers |
Whether to ignore numbers when comparing strings.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
RegexMatch
¶
Bases: SingleKeyEvalConfig
Configuration for a regex match string evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
flags |
The flags to pass to the regex. Example:
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
ScoreString
¶
Bases: SingleKeyEvalConfig
Configuration for a score string evaluator.
This is like the criteria evaluator but it is configured by default to return a score on the scale from 1-10.
It is recommended to normalize these scores
by setting normalize_by to 10.
| ATTRIBUTE | DESCRIPTION |
|---|---|
criteria |
The criteria to evaluate.
TYPE:
|
llm |
The language model to use for the evaluation chain.
TYPE:
|
normalize_by |
If you want to normalize the score, the denominator to use. If not provided, the score will be between 1 and 10.
TYPE:
|
prompt |
The prompt template to use for evaluation.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
LabeledScoreString
¶
Bases: ScoreString
Configuration for a labeled score string evaluator.
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
arun_on_dataset
async
¶
arun_on_dataset(
client: Client | None,
dataset_name: str,
llm_or_chain_factory: MODEL_OR_CHAIN_FACTORY,
*,
evaluation: RunEvalConfig | None = None,
dataset_version: datetime | str | None = None,
concurrency_level: int = 5,
project_name: str | None = None,
project_metadata: dict[str, Any] | None = None,
verbose: bool = False,
revision_id: str | None = None,
**kwargs: Any,
) -> dict[str, Any]
Run on dataset.
Run the Chain or language model on a dataset and store traces to the specified project name.
For the (usually faster) async version of this function,
see arun_on_dataset.
| PARAMETER | DESCRIPTION |
|---|---|
dataset_name
|
Name of the dataset to run the chain on.
TYPE:
|
llm_or_chain_factory
|
Language model or Chain constructor to run over the dataset. The Chain constructor is used to permit independent calls on each example without carrying over state.
TYPE:
|
evaluation
|
Configuration for evaluators to run on the results of the chain.
TYPE:
|
dataset_version
|
Optional version of the dataset. |
concurrency_level
|
The number of async tasks to run concurrently.
TYPE:
|
project_name
|
Name of the project to store the traces in.
Defaults to
TYPE:
|
project_metadata
|
Optional metadata to add to the project. Useful for storing information the test variant. (prompt version, model version, etc.) |
client
|
LangSmith client to use to access the dataset and to log feedback and run traces.
TYPE:
|
verbose
|
Whether to print progress.
TYPE:
|
revision_id
|
Optional revision identifier to assign this test run to track the performance of different versions of your system.
TYPE:
|
**kwargs
|
Should not be used, but is provided for backwards compatibility.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
dict[str, Any]
|
|
Examples:
from langsmith import Client
from langchain_openai import ChatOpenAI
from langchain_classic.chains import LLMChain
from langchain_classic.smith import smith_eval.RunEvalConfig, run_on_dataset
# Chains may have memory. Passing in a constructor function lets the
# evaluation framework avoid cross-contamination between runs.
def construct_chain():
model = ChatOpenAI(temperature=0)
chain = LLMChain.from_string(
model,
"What's the answer to {your_input_key}"
)
return chain
# Load off-the-shelf evaluators via config or the EvaluatorType (string or enum)
evaluation_config = smith_eval.RunEvalConfig(
evaluators=[
"qa", # "Correctness" against a reference answer
"embedding_distance",
smith_eval.RunEvalConfig.Criteria("helpfulness"),
smith_eval.RunEvalConfig.Criteria({
"fifth-grader-score": "Do you have to be smarter than a fifth "
"grader to answer this question?"
}),
]
)
client = Client()
await arun_on_dataset(
client,
dataset_name="<my_dataset_name>",
llm_or_chain_factory=construct_chain,
evaluation=evaluation_config,
)
StringEvaluator or
LangSmith'sRunEvaluator` classes.
from typing import Optional
from langchain_classic.evaluation import StringEvaluator
class MyStringEvaluator(StringEvaluator):
@property
def requires_input(self) -> bool:
return False
@property
def requires_reference(self) -> bool:
return True
@property
def evaluation_name(self) -> str:
return "exact_match"
def _evaluate_strings(
self, prediction, reference=None, input=None, **kwargs
) -> dict:
return {"score": prediction == reference}
evaluation_config = smith_eval.RunEvalConfig(
custom_evaluators=[MyStringEvaluator()],
)
await arun_on_dataset(
client,
dataset_name="<my_dataset_name>",
llm_or_chain_factory=construct_chain,
evaluation=evaluation_config,
)
run_on_dataset
¶
run_on_dataset(
client: Client | None,
dataset_name: str,
llm_or_chain_factory: MODEL_OR_CHAIN_FACTORY,
*,
evaluation: RunEvalConfig | None = None,
dataset_version: datetime | str | None = None,
concurrency_level: int = 5,
project_name: str | None = None,
project_metadata: dict[str, Any] | None = None,
verbose: bool = False,
revision_id: str | None = None,
**kwargs: Any,
) -> dict[str, Any]
Run on dataset.
Run the Chain or language model on a dataset and store traces to the specified project name.
For the (usually faster) async version of this function,
see arun_on_dataset.
| PARAMETER | DESCRIPTION |
|---|---|
dataset_name
|
Name of the dataset to run the chain on.
TYPE:
|
llm_or_chain_factory
|
Language model or Chain constructor to run over the dataset. The Chain constructor is used to permit independent calls on each example without carrying over state.
TYPE:
|
evaluation
|
Configuration for evaluators to run on the results of the chain.
TYPE:
|
dataset_version
|
Optional version of the dataset. |
concurrency_level
|
The number of async tasks to run concurrently.
TYPE:
|
project_name
|
Name of the project to store the traces in.
Defaults to
TYPE:
|
project_metadata
|
Optional metadata to add to the project. Useful for storing information the test variant. (prompt version, model version, etc.) |
client
|
LangSmith client to use to access the dataset and to log feedback and run traces.
TYPE:
|
verbose
|
Whether to print progress.
TYPE:
|
revision_id
|
Optional revision identifier to assign this test run to track the performance of different versions of your system.
TYPE:
|
**kwargs
|
Should not be used, but is provided for backwards compatibility.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
dict[str, Any]
|
|
Examples:
from langsmith import Client
from langchain_openai import ChatOpenAI
from langchain_classic.chains import LLMChain
from langchain_classic.smith import smith_eval.RunEvalConfig, run_on_dataset
# Chains may have memory. Passing in a constructor function lets the
# evaluation framework avoid cross-contamination between runs.
def construct_chain():
model = ChatOpenAI(temperature=0)
chain = LLMChain.from_string(
model,
"What's the answer to {your_input_key}"
)
return chain
# Load off-the-shelf evaluators via config or the EvaluatorType (string or enum)
evaluation_config = smith_eval.RunEvalConfig(
evaluators=[
"qa", # "Correctness" against a reference answer
"embedding_distance",
smith_eval.RunEvalConfig.Criteria("helpfulness"),
smith_eval.RunEvalConfig.Criteria({
"fifth-grader-score": "Do you have to be smarter than a fifth "
"grader to answer this question?"
}),
]
)
client = Client()
run_on_dataset(
client,
dataset_name="<my_dataset_name>",
llm_or_chain_factory=construct_chain,
evaluation=evaluation_config,
)
You can also create custom evaluators by subclassing the StringEvaluator or
LangSmith's RunEvaluator classes.
from typing import Optional
from langchain_classic.evaluation import StringEvaluator
class MyStringEvaluator(StringEvaluator):
@property
def requires_input(self) -> bool:
return False
@property
def requires_reference(self) -> bool:
return True
@property
def evaluation_name(self) -> str:
return "exact_match"
def _evaluate_strings(
self, prediction, reference=None, input=None, **kwargs
) -> dict:
return {"score": prediction == reference}
evaluation_config = smith_eval.RunEvalConfig(
custom_evaluators=[MyStringEvaluator()],
)
run_on_dataset(
client,
dataset_name="<my_dataset_name>",
llm_or_chain_factory=construct_chain,
evaluation=evaluation_config,
)
langchain_classic.smith.evaluation.config
¶
Configuration for run evaluators.
EvalConfig
¶
Bases: BaseModel
Configuration for a given run evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
evaluator_type |
The type of evaluator to use.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
RunEvalConfig
¶
Bases: BaseModel
Configuration for a run evaluation.
evaluators
class-attribute
instance-attribute
¶
Configurations for which evaluators to apply to the dataset run.
Each can be the string of an
EvaluatorType <langchain.evaluation.schema.EvaluatorType>, such
as EvaluatorType.QA, the evaluator type string ("qa"), or a configuration for a
given evaluator
(e.g.,
RunEvalConfig.QA <langchain.smith.evaluation.config.RunEvalConfig.QA>).
custom_evaluators
class-attribute
instance-attribute
¶
custom_evaluators: list[CUSTOM_EVALUATOR_TYPE] | None = None
Custom evaluators to apply to the dataset run.
batch_evaluators
class-attribute
instance-attribute
¶
batch_evaluators: list[BATCH_EVALUATOR_LIKE] | None = None
Evaluators that run on an aggregate/batch level.
These generate one or more metrics that are assigned to the full test run. As a result, they are not associated with individual traces.
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
input_key
class-attribute
instance-attribute
¶
input_key: str | None = None
The key from the traced run's inputs dictionary to use to represent the input. If not provided, it will be inferred automatically.
eval_llm
class-attribute
instance-attribute
¶
eval_llm: BaseLanguageModel | None = None
The language model to pass to any evaluators that require one.
Criteria
¶
Bases: SingleKeyEvalConfig
Configuration for a reference-free criteria evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
criteria |
The criteria to evaluate.
TYPE:
|
llm |
The language model to use for the evaluation chain.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
LabeledCriteria
¶
Bases: SingleKeyEvalConfig
Configuration for a labeled (with references) criteria evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
criteria |
The criteria to evaluate.
TYPE:
|
llm |
The language model to use for the evaluation chain.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
EmbeddingDistance
¶
Bases: SingleKeyEvalConfig
Configuration for an embedding distance evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
embeddings |
The embeddings to use for computing the distance.
TYPE:
|
distance_metric |
The distance metric to use for computing the distance.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
StringDistance
¶
Bases: SingleKeyEvalConfig
Configuration for a string distance evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
distance |
The string distance metric to use (
TYPE:
|
normalize_score |
Whether to normalize the distance to between 0 and 1. Applies only to the Levenshtein and Damerau-Levenshtein distances.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
QA
¶
Bases: SingleKeyEvalConfig
Configuration for a QA evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
prompt |
The prompt template to use for generating the question.
TYPE:
|
llm |
The language model to use for the evaluation chain.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
ContextQA
¶
Bases: SingleKeyEvalConfig
Configuration for a context-based QA evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
prompt |
The prompt template to use for generating the question.
TYPE:
|
llm |
The language model to use for the evaluation chain.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
CoTQA
¶
Bases: SingleKeyEvalConfig
Configuration for a context-based QA evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
prompt |
The prompt template to use for generating the question.
TYPE:
|
llm |
The language model to use for the evaluation chain.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
JsonValidity
¶
Bases: SingleKeyEvalConfig
Configuration for a json validity evaluator.
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
JsonEqualityEvaluator
¶
Bases: EvalConfig
Configuration for a json equality evaluator.
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
ExactMatch
¶
Bases: SingleKeyEvalConfig
Configuration for an exact match string evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
ignore_case |
Whether to ignore case when comparing strings.
TYPE:
|
ignore_punctuation |
Whether to ignore punctuation when comparing strings.
TYPE:
|
ignore_numbers |
Whether to ignore numbers when comparing strings.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
RegexMatch
¶
Bases: SingleKeyEvalConfig
Configuration for a regex match string evaluator.
| ATTRIBUTE | DESCRIPTION |
|---|---|
flags |
The flags to pass to the regex. Example:
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
ScoreString
¶
Bases: SingleKeyEvalConfig
Configuration for a score string evaluator.
This is like the criteria evaluator but it is configured by default to return a score on the scale from 1-10.
It is recommended to normalize these scores
by setting normalize_by to 10.
| ATTRIBUTE | DESCRIPTION |
|---|---|
criteria |
The criteria to evaluate.
TYPE:
|
llm |
The language model to use for the evaluation chain.
TYPE:
|
normalize_by |
If you want to normalize the score, the denominator to use. If not provided, the score will be between 1 and 10.
TYPE:
|
prompt |
The prompt template to use for evaluation.
TYPE:
|
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
LabeledScoreString
¶
Bases: ScoreString
Configuration for a labeled score string evaluator.
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
SingleKeyEvalConfig
¶
Bases: EvalConfig
Configuration for a run evaluator that only requires a single key.
| METHOD | DESCRIPTION |
|---|---|
get_kwargs |
Get the keyword arguments for the |
reference_key
class-attribute
instance-attribute
¶
reference_key: str | None = None
The key in the dataset run to use as the reference string. If not provided, we will attempt to infer automatically.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the traced run's outputs dictionary to use to represent the prediction. If not provided, it will be inferred automatically.
langchain_classic.smith.evaluation.progress
¶
A simple progress bar for the console.
ProgressBarCallback
¶
Bases: BaseCallbackHandler
A simple progress bar for the console.
| METHOD | DESCRIPTION |
|---|---|
__init__ |
Initialize the progress bar. |
increment |
Increment the counter and update the progress bar. |
on_chain_error |
Run when chain errors. |
on_chain_end |
Run when chain ends running. |
on_retriever_error |
Run when Retriever errors. |
on_retriever_end |
Run when Retriever ends running. |
on_llm_error |
Run when LLM errors. |
on_llm_end |
Run when LLM ends running. |
on_tool_error |
Run when tool errors. |
on_tool_end |
Run when the tool ends running. |
on_text |
Run on an arbitrary text. |
on_retry |
Run on a retry event. |
on_custom_event |
Override to define a handler for a custom event. |
on_llm_start |
Run when LLM starts running. |
on_chat_model_start |
Run when a chat model starts running. |
on_retriever_start |
Run when the Retriever starts running. |
on_chain_start |
Run when a chain starts running. |
on_tool_start |
Run when the tool starts running. |
on_agent_action |
Run on agent action. |
on_agent_finish |
Run on the agent end. |
on_llm_new_token |
Run on new output token. Only available when streaming is enabled. |
raise_error
class-attribute
instance-attribute
¶
raise_error: bool = False
Whether to raise an error if an exception occurs.
run_inline
class-attribute
instance-attribute
¶
run_inline: bool = False
Whether to run the callback inline.
__init__
¶
Initialize the progress bar.
| PARAMETER | DESCRIPTION |
|---|---|
total
|
The total number of items to be processed.
TYPE:
|
ncols
|
The character width of the progress bar.
TYPE:
|
end_with
|
Last string to print after progress bar reaches end.
TYPE:
|
**kwargs
|
Additional keyword arguments.
|
on_chain_error
¶
on_chain_error(
error: BaseException,
*,
run_id: UUID,
parent_run_id: UUID | None = None,
**kwargs: Any,
) -> Any
Run when chain errors.
| PARAMETER | DESCRIPTION |
|---|---|
error
|
The error that occurred.
TYPE:
|
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_chain_end
¶
on_chain_end(
outputs: dict[str, Any],
*,
run_id: UUID,
parent_run_id: UUID | None = None,
**kwargs: Any,
) -> Any
Run when chain ends running.
| PARAMETER | DESCRIPTION |
|---|---|
outputs
|
The outputs of the chain. |
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_retriever_error
¶
on_retriever_error(
error: BaseException,
*,
run_id: UUID,
parent_run_id: UUID | None = None,
**kwargs: Any,
) -> Any
Run when Retriever errors.
| PARAMETER | DESCRIPTION |
|---|---|
error
|
The error that occurred.
TYPE:
|
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_retriever_end
¶
on_retriever_end(
documents: Sequence[Document],
*,
run_id: UUID,
parent_run_id: UUID | None = None,
**kwargs: Any,
) -> Any
Run when Retriever ends running.
| PARAMETER | DESCRIPTION |
|---|---|
documents
|
The documents retrieved. |
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_llm_error
¶
on_llm_error(
error: BaseException,
*,
run_id: UUID,
parent_run_id: UUID | None = None,
**kwargs: Any,
) -> Any
Run when LLM errors.
| PARAMETER | DESCRIPTION |
|---|---|
error
|
The error that occurred.
TYPE:
|
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_llm_end
¶
on_llm_end(
response: LLMResult,
*,
run_id: UUID,
parent_run_id: UUID | None = None,
**kwargs: Any,
) -> Any
Run when LLM ends running.
| PARAMETER | DESCRIPTION |
|---|---|
response
|
The response which was generated.
TYPE:
|
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_tool_error
¶
on_tool_error(
error: BaseException,
*,
run_id: UUID,
parent_run_id: UUID | None = None,
**kwargs: Any,
) -> Any
Run when tool errors.
| PARAMETER | DESCRIPTION |
|---|---|
error
|
The error that occurred.
TYPE:
|
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_tool_end
¶
on_tool_end(
output: str, *, run_id: UUID, parent_run_id: UUID | None = None, **kwargs: Any
) -> Any
Run when the tool ends running.
| PARAMETER | DESCRIPTION |
|---|---|
output
|
The output of the tool.
TYPE:
|
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_text
¶
on_retry
¶
on_retry(
retry_state: RetryCallState,
*,
run_id: UUID,
parent_run_id: UUID | None = None,
**kwargs: Any,
) -> Any
Run on a retry event.
| PARAMETER | DESCRIPTION |
|---|---|
retry_state
|
The retry state.
TYPE:
|
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_custom_event
¶
on_custom_event(
name: str,
data: Any,
*,
run_id: UUID,
tags: list[str] | None = None,
metadata: dict[str, Any] | None = None,
**kwargs: Any,
) -> Any
Override to define a handler for a custom event.
| PARAMETER | DESCRIPTION |
|---|---|
name
|
The name of the custom event.
TYPE:
|
data
|
The data for the custom event. Format will match the format specified by the user.
TYPE:
|
run_id
|
The ID of the run.
TYPE:
|
tags
|
The tags associated with the custom event (includes inherited tags). |
metadata
|
The metadata associated with the custom event (includes inherited metadata). |
on_llm_start
¶
on_llm_start(
serialized: dict[str, Any],
prompts: list[str],
*,
run_id: UUID,
parent_run_id: UUID | None = None,
tags: list[str] | None = None,
metadata: dict[str, Any] | None = None,
**kwargs: Any,
) -> Any
Run when LLM starts running.
Warning
This method is called for non-chat models (regular LLMs). If you're
implementing a handler for a chat model, you should use
on_chat_model_start instead.
| PARAMETER | DESCRIPTION |
|---|---|
serialized
|
The serialized LLM. |
prompts
|
The prompts. |
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
tags
|
The tags. |
metadata
|
The metadata. |
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_chat_model_start
¶
on_chat_model_start(
serialized: dict[str, Any],
messages: list[list[BaseMessage]],
*,
run_id: UUID,
parent_run_id: UUID | None = None,
tags: list[str] | None = None,
metadata: dict[str, Any] | None = None,
**kwargs: Any,
) -> Any
Run when a chat model starts running.
Warning
This method is called for chat models. If you're implementing a handler for
a non-chat model, you should use on_llm_start instead.
| PARAMETER | DESCRIPTION |
|---|---|
serialized
|
The serialized chat model. |
messages
|
The messages.
TYPE:
|
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
tags
|
The tags. |
metadata
|
The metadata. |
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_retriever_start
¶
on_retriever_start(
serialized: dict[str, Any],
query: str,
*,
run_id: UUID,
parent_run_id: UUID | None = None,
tags: list[str] | None = None,
metadata: dict[str, Any] | None = None,
**kwargs: Any,
) -> Any
Run when the Retriever starts running.
| PARAMETER | DESCRIPTION |
|---|---|
serialized
|
The serialized Retriever. |
query
|
The query.
TYPE:
|
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
tags
|
The tags. |
metadata
|
The metadata. |
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_chain_start
¶
on_chain_start(
serialized: dict[str, Any],
inputs: dict[str, Any],
*,
run_id: UUID,
parent_run_id: UUID | None = None,
tags: list[str] | None = None,
metadata: dict[str, Any] | None = None,
**kwargs: Any,
) -> Any
Run when a chain starts running.
| PARAMETER | DESCRIPTION |
|---|---|
serialized
|
The serialized chain. |
inputs
|
The inputs. |
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
tags
|
The tags. |
metadata
|
The metadata. |
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_tool_start
¶
on_tool_start(
serialized: dict[str, Any],
input_str: str,
*,
run_id: UUID,
parent_run_id: UUID | None = None,
tags: list[str] | None = None,
metadata: dict[str, Any] | None = None,
inputs: dict[str, Any] | None = None,
**kwargs: Any,
) -> Any
Run when the tool starts running.
| PARAMETER | DESCRIPTION |
|---|---|
serialized
|
The serialized chain. |
input_str
|
The input string.
TYPE:
|
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
tags
|
The tags. |
metadata
|
The metadata. |
inputs
|
The inputs. |
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_agent_action
¶
on_agent_action(
action: AgentAction,
*,
run_id: UUID,
parent_run_id: UUID | None = None,
**kwargs: Any,
) -> Any
Run on agent action.
| PARAMETER | DESCRIPTION |
|---|---|
action
|
The agent action.
TYPE:
|
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_agent_finish
¶
on_agent_finish(
finish: AgentFinish,
*,
run_id: UUID,
parent_run_id: UUID | None = None,
**kwargs: Any,
) -> Any
Run on the agent end.
| PARAMETER | DESCRIPTION |
|---|---|
finish
|
The agent finish.
TYPE:
|
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
**kwargs
|
Additional keyword arguments.
TYPE:
|
on_llm_new_token
¶
on_llm_new_token(
token: str,
*,
chunk: GenerationChunk | ChatGenerationChunk | None = None,
run_id: UUID,
parent_run_id: UUID | None = None,
**kwargs: Any,
) -> Any
Run on new output token. Only available when streaming is enabled.
For both chat models and non-chat models (legacy LLMs).
| PARAMETER | DESCRIPTION |
|---|---|
token
|
The new token.
TYPE:
|
chunk
|
The new generated chunk, containing content and other information.
TYPE:
|
run_id
|
The run ID. This is the ID of the current run.
TYPE:
|
parent_run_id
|
The parent run ID. This is the ID of the parent run.
TYPE:
|
**kwargs
|
Additional keyword arguments.
TYPE:
|
langchain_classic.smith.evaluation.runner_utils
¶
Utilities for running language models or Chains over datasets.
| FUNCTION | DESCRIPTION |
|---|---|
arun_on_dataset |
Run on dataset. |
run_on_dataset |
Run on dataset. |
ChatModelInput
¶
EvalError
¶
Bases: dict
Your architecture raised an error.
| METHOD | DESCRIPTION |
|---|---|
__init__ |
Initialize the |
__getattr__ |
Get an attribute from the |
__init__
¶
__init__(Error: BaseException, **kwargs: Any) -> None
Initialize the EvalError with an error and additional attributes.
| PARAMETER | DESCRIPTION |
|---|---|
Error
|
The error that occurred.
TYPE:
|
**kwargs
|
Additional attributes to include in the error.
TYPE:
|
TestResult
¶
Bases: dict
A dictionary of the results of a single test run.
| METHOD | DESCRIPTION |
|---|---|
get_aggregate_feedback |
Return quantiles for the feedback scores. |
to_dataframe |
Convert the results to a dataframe. |
get_aggregate_feedback
¶
Return quantiles for the feedback scores.
This method calculates and prints the quantiles for the feedback scores across all feedback keys.
| RETURNS | DESCRIPTION |
|---|---|
DataFrame
|
A DataFrame containing the quantiles for each feedback key. |
arun_on_dataset
async
¶
arun_on_dataset(
client: Client | None,
dataset_name: str,
llm_or_chain_factory: MODEL_OR_CHAIN_FACTORY,
*,
evaluation: RunEvalConfig | None = None,
dataset_version: datetime | str | None = None,
concurrency_level: int = 5,
project_name: str | None = None,
project_metadata: dict[str, Any] | None = None,
verbose: bool = False,
revision_id: str | None = None,
**kwargs: Any,
) -> dict[str, Any]
Run on dataset.
Run the Chain or language model on a dataset and store traces to the specified project name.
For the (usually faster) async version of this function,
see arun_on_dataset.
| PARAMETER | DESCRIPTION |
|---|---|
dataset_name
|
Name of the dataset to run the chain on.
TYPE:
|
llm_or_chain_factory
|
Language model or Chain constructor to run over the dataset. The Chain constructor is used to permit independent calls on each example without carrying over state.
TYPE:
|
evaluation
|
Configuration for evaluators to run on the results of the chain.
TYPE:
|
dataset_version
|
Optional version of the dataset. |
concurrency_level
|
The number of async tasks to run concurrently.
TYPE:
|
project_name
|
Name of the project to store the traces in.
Defaults to
TYPE:
|
project_metadata
|
Optional metadata to add to the project. Useful for storing information the test variant. (prompt version, model version, etc.) |
client
|
LangSmith client to use to access the dataset and to log feedback and run traces.
TYPE:
|
verbose
|
Whether to print progress.
TYPE:
|
revision_id
|
Optional revision identifier to assign this test run to track the performance of different versions of your system.
TYPE:
|
**kwargs
|
Should not be used, but is provided for backwards compatibility.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
dict[str, Any]
|
|
Examples:
from langsmith import Client
from langchain_openai import ChatOpenAI
from langchain_classic.chains import LLMChain
from langchain_classic.smith import smith_eval.RunEvalConfig, run_on_dataset
# Chains may have memory. Passing in a constructor function lets the
# evaluation framework avoid cross-contamination between runs.
def construct_chain():
model = ChatOpenAI(temperature=0)
chain = LLMChain.from_string(
model,
"What's the answer to {your_input_key}"
)
return chain
# Load off-the-shelf evaluators via config or the EvaluatorType (string or enum)
evaluation_config = smith_eval.RunEvalConfig(
evaluators=[
"qa", # "Correctness" against a reference answer
"embedding_distance",
smith_eval.RunEvalConfig.Criteria("helpfulness"),
smith_eval.RunEvalConfig.Criteria({
"fifth-grader-score": "Do you have to be smarter than a fifth "
"grader to answer this question?"
}),
]
)
client = Client()
await arun_on_dataset(
client,
dataset_name="<my_dataset_name>",
llm_or_chain_factory=construct_chain,
evaluation=evaluation_config,
)
StringEvaluator or
LangSmith'sRunEvaluator` classes.
from typing import Optional
from langchain_classic.evaluation import StringEvaluator
class MyStringEvaluator(StringEvaluator):
@property
def requires_input(self) -> bool:
return False
@property
def requires_reference(self) -> bool:
return True
@property
def evaluation_name(self) -> str:
return "exact_match"
def _evaluate_strings(
self, prediction, reference=None, input=None, **kwargs
) -> dict:
return {"score": prediction == reference}
evaluation_config = smith_eval.RunEvalConfig(
custom_evaluators=[MyStringEvaluator()],
)
await arun_on_dataset(
client,
dataset_name="<my_dataset_name>",
llm_or_chain_factory=construct_chain,
evaluation=evaluation_config,
)
run_on_dataset
¶
run_on_dataset(
client: Client | None,
dataset_name: str,
llm_or_chain_factory: MODEL_OR_CHAIN_FACTORY,
*,
evaluation: RunEvalConfig | None = None,
dataset_version: datetime | str | None = None,
concurrency_level: int = 5,
project_name: str | None = None,
project_metadata: dict[str, Any] | None = None,
verbose: bool = False,
revision_id: str | None = None,
**kwargs: Any,
) -> dict[str, Any]
Run on dataset.
Run the Chain or language model on a dataset and store traces to the specified project name.
For the (usually faster) async version of this function,
see arun_on_dataset.
| PARAMETER | DESCRIPTION |
|---|---|
dataset_name
|
Name of the dataset to run the chain on.
TYPE:
|
llm_or_chain_factory
|
Language model or Chain constructor to run over the dataset. The Chain constructor is used to permit independent calls on each example without carrying over state.
TYPE:
|
evaluation
|
Configuration for evaluators to run on the results of the chain.
TYPE:
|
dataset_version
|
Optional version of the dataset. |
concurrency_level
|
The number of async tasks to run concurrently.
TYPE:
|
project_name
|
Name of the project to store the traces in.
Defaults to
TYPE:
|
project_metadata
|
Optional metadata to add to the project. Useful for storing information the test variant. (prompt version, model version, etc.) |
client
|
LangSmith client to use to access the dataset and to log feedback and run traces.
TYPE:
|
verbose
|
Whether to print progress.
TYPE:
|
revision_id
|
Optional revision identifier to assign this test run to track the performance of different versions of your system.
TYPE:
|
**kwargs
|
Should not be used, but is provided for backwards compatibility.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
dict[str, Any]
|
|
Examples:
from langsmith import Client
from langchain_openai import ChatOpenAI
from langchain_classic.chains import LLMChain
from langchain_classic.smith import smith_eval.RunEvalConfig, run_on_dataset
# Chains may have memory. Passing in a constructor function lets the
# evaluation framework avoid cross-contamination between runs.
def construct_chain():
model = ChatOpenAI(temperature=0)
chain = LLMChain.from_string(
model,
"What's the answer to {your_input_key}"
)
return chain
# Load off-the-shelf evaluators via config or the EvaluatorType (string or enum)
evaluation_config = smith_eval.RunEvalConfig(
evaluators=[
"qa", # "Correctness" against a reference answer
"embedding_distance",
smith_eval.RunEvalConfig.Criteria("helpfulness"),
smith_eval.RunEvalConfig.Criteria({
"fifth-grader-score": "Do you have to be smarter than a fifth "
"grader to answer this question?"
}),
]
)
client = Client()
run_on_dataset(
client,
dataset_name="<my_dataset_name>",
llm_or_chain_factory=construct_chain,
evaluation=evaluation_config,
)
You can also create custom evaluators by subclassing the StringEvaluator or
LangSmith's RunEvaluator classes.
from typing import Optional
from langchain_classic.evaluation import StringEvaluator
class MyStringEvaluator(StringEvaluator):
@property
def requires_input(self) -> bool:
return False
@property
def requires_reference(self) -> bool:
return True
@property
def evaluation_name(self) -> str:
return "exact_match"
def _evaluate_strings(
self, prediction, reference=None, input=None, **kwargs
) -> dict:
return {"score": prediction == reference}
evaluation_config = smith_eval.RunEvalConfig(
custom_evaluators=[MyStringEvaluator()],
)
run_on_dataset(
client,
dataset_name="<my_dataset_name>",
llm_or_chain_factory=construct_chain,
evaluation=evaluation_config,
)
langchain_classic.smith.evaluation.string_run_evaluator
¶
Run evaluator wrapper for string evaluators.
ChainStringRunMapper
¶
Bases: StringRunMapper
Extract items to evaluate from the run object from a chain.
| METHOD | DESCRIPTION |
|---|---|
map |
Maps the Run to a dictionary. |
__init__ |
|
is_lc_serializable |
Is this class serializable? |
get_lc_namespace |
Get the namespace of the LangChain object. |
lc_id |
Return a unique identifier for this class for serialization purposes. |
to_json |
Serialize the object to JSON. |
to_json_not_implemented |
Serialize a "not implemented" object. |
__call__ |
Maps the Run to a dictionary. |
input_key
class-attribute
instance-attribute
¶
input_key: str | None = None
The key from the model Run's inputs to use as the eval input. If not provided, will use the only input key or raise an error if there are multiple.
prediction_key
class-attribute
instance-attribute
¶
prediction_key: str | None = None
The key from the model Run's outputs to use as the eval prediction. If not provided, will use the only output key or raise an error if there are multiple.
lc_secrets
property
¶
A map of constructor argument names to secret ids.
For example, {"openai_api_key": "OPENAI_API_KEY"}
lc_attributes
property
¶
lc_attributes: dict
List of attribute names that should be included in the serialized kwargs.
These attributes must be accepted by the constructor.
Default is an empty dictionary.
is_lc_serializable
classmethod
¶
is_lc_serializable() -> bool
Is this class serializable?
By design, even if a class inherits from Serializable, it is not serializable
by default. This is to prevent accidental serialization of objects that should
not be serialized.
| RETURNS | DESCRIPTION |
|---|---|
bool
|
Whether the class is serializable. Default is |
get_lc_namespace
classmethod
¶
lc_id
classmethod
¶
Return a unique identifier for this class for serialization purposes.
The unique identifier is a list of strings that describes the path to the object.
For example, for the class langchain.llms.openai.OpenAI, the id is
["langchain", "llms", "openai", "OpenAI"].
to_json
¶
Serialize the object to JSON.
| RAISES | DESCRIPTION |
|---|---|
ValueError
|
If the class has deprecated attributes. |
| RETURNS | DESCRIPTION |
|---|---|
SerializedConstructor | SerializedNotImplemented
|
A JSON serializable object or a |
to_json_not_implemented
¶
Serialize a "not implemented" object.
| RETURNS | DESCRIPTION |
|---|---|
SerializedNotImplemented
|
|
LLMStringRunMapper
¶
Bases: StringRunMapper
Extract items to evaluate from the run object.
| METHOD | DESCRIPTION |
|---|---|
serialize_chat_messages |
Extract the input messages from the run. |
serialize_inputs |
Serialize inputs. |
serialize_outputs |
Serialize outputs. |
map |
Maps the Run to a dictionary. |
__init__ |
|
is_lc_serializable |
Is this class serializable? |
get_lc_namespace |
Get the namespace of the LangChain object. |
lc_id |
Return a unique identifier for this class for serialization purposes. |
to_json |
Serialize the object to JSON. |
to_json_not_implemented |
Serialize a "not implemented" object. |
__call__ |
Maps the Run to a dictionary. |
lc_secrets
property
¶
A map of constructor argument names to secret ids.
For example, {"openai_api_key": "OPENAI_API_KEY"}
lc_attributes
property
¶
lc_attributes: dict
List of attribute names that should be included in the serialized kwargs.
These attributes must be accepted by the constructor.
Default is an empty dictionary.
serialize_chat_messages
¶
Extract the input messages from the run.
serialize_inputs
¶
Serialize inputs.
| PARAMETER | DESCRIPTION |
|---|---|
inputs
|
The inputs from the run, expected to contain prompts or messages.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
str
|
The serialized input text from the prompts or messages. |
| RAISES | DESCRIPTION |
|---|---|
ValueError
|
If neither prompts nor messages are found in the inputs. |
serialize_outputs
¶
Serialize outputs.
| PARAMETER | DESCRIPTION |
|---|---|
outputs
|
The outputs from the run, expected to contain generations.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
str
|
The serialized output text from the first generation. |
| RAISES | DESCRIPTION |
|---|---|
ValueError
|
If no generations are found in the outputs, |
is_lc_serializable
classmethod
¶
is_lc_serializable() -> bool
Is this class serializable?
By design, even if a class inherits from Serializable, it is not serializable
by default. This is to prevent accidental serialization of objects that should
not be serialized.
| RETURNS | DESCRIPTION |
|---|---|
bool
|
Whether the class is serializable. Default is |
get_lc_namespace
classmethod
¶
lc_id
classmethod
¶
Return a unique identifier for this class for serialization purposes.
The unique identifier is a list of strings that describes the path to the object.
For example, for the class langchain.llms.openai.OpenAI, the id is
["langchain", "llms", "openai", "OpenAI"].
to_json
¶
Serialize the object to JSON.
| RAISES | DESCRIPTION |
|---|---|
ValueError
|
If the class has deprecated attributes. |
| RETURNS | DESCRIPTION |
|---|---|
SerializedConstructor | SerializedNotImplemented
|
A JSON serializable object or a |
to_json_not_implemented
¶
Serialize a "not implemented" object.
| RETURNS | DESCRIPTION |
|---|---|
SerializedNotImplemented
|
|
StringExampleMapper
¶
Bases: Serializable
Map an example, or row in the dataset, to the inputs of an evaluation.
| METHOD | DESCRIPTION |
|---|---|
serialize_chat_messages |
Extract the input messages from the run. |
map |
Maps the Example, or dataset row to a dictionary. |
__call__ |
Maps the Run and Example to a dictionary. |
__init__ |
|
is_lc_serializable |
Is this class serializable? |
get_lc_namespace |
Get the namespace of the LangChain object. |
lc_id |
Return a unique identifier for this class for serialization purposes. |
to_json |
Serialize the object to JSON. |
to_json_not_implemented |
Serialize a "not implemented" object. |
lc_secrets
property
¶
A map of constructor argument names to secret ids.
For example, {"openai_api_key": "OPENAI_API_KEY"}
lc_attributes
property
¶
lc_attributes: dict
List of attribute names that should be included in the serialized kwargs.
These attributes must be accepted by the constructor.
Default is an empty dictionary.
serialize_chat_messages
¶
Extract the input messages from the run.
is_lc_serializable
classmethod
¶
is_lc_serializable() -> bool
Is this class serializable?
By design, even if a class inherits from Serializable, it is not serializable
by default. This is to prevent accidental serialization of objects that should
not be serialized.
| RETURNS | DESCRIPTION |
|---|---|
bool
|
Whether the class is serializable. Default is |
get_lc_namespace
classmethod
¶
lc_id
classmethod
¶
Return a unique identifier for this class for serialization purposes.
The unique identifier is a list of strings that describes the path to the object.
For example, for the class langchain.llms.openai.OpenAI, the id is
["langchain", "llms", "openai", "OpenAI"].
to_json
¶
Serialize the object to JSON.
| RAISES | DESCRIPTION |
|---|---|
ValueError
|
If the class has deprecated attributes. |
| RETURNS | DESCRIPTION |
|---|---|
SerializedConstructor | SerializedNotImplemented
|
A JSON serializable object or a |
to_json_not_implemented
¶
Serialize a "not implemented" object.
| RETURNS | DESCRIPTION |
|---|---|
SerializedNotImplemented
|
|
StringRunEvaluatorChain
¶
Bases: Chain, RunEvaluator
Evaluate Run and optional examples.
| METHOD | DESCRIPTION |
|---|---|
evaluate_run |
Evaluate an example. |
aevaluate_run |
Evaluate an example. |
from_run_and_data_type |
Create a StringRunEvaluatorChain. |
get_name |
Get the name of the |
get_input_schema |
Get a Pydantic model that can be used to validate input to the |
get_input_jsonschema |
Get a JSON schema that represents the input to the |
get_output_schema |
Get a Pydantic model that can be used to validate output to the |
get_output_jsonschema |
Get a JSON schema that represents the output of the |
config_schema |
The type of config this |
get_config_jsonschema |
Get a JSON schema that represents the config of the |
get_graph |
Return a graph representation of this |
get_prompts |
Return a list of prompts used by this |
__or__ |
Runnable "or" operator. |
__ror__ |
Runnable "reverse-or" operator. |
pipe |
Pipe |
pick |
Pick keys from the output |
assign |
Assigns new fields to the |
invoke |
Transform a single input into an output. |
ainvoke |
Transform a single input into an output. |
batch |
Default implementation runs invoke in parallel using a thread pool executor. |
batch_as_completed |
Run |
abatch |
Default implementation runs |
abatch_as_completed |
Run |
stream |
Default implementation of |
astream |
Default implementation of |
astream_log |
Stream all output from a |
astream_events |
Generate a stream of events. |
transform |
Transform inputs to outputs. |
atransform |
Transform inputs to outputs. |
bind |
Bind arguments to a |
with_config |
Bind config to a |
with_listeners |
Bind lifecycle listeners to a |
with_alisteners |
Bind async lifecycle listeners to a |
with_types |
Bind input and output types to a |
with_retry |
Create a new |
map |
Return a new |
with_fallbacks |
Add fallbacks to a |
as_tool |
Create a |
__init__ |
|
is_lc_serializable |
Is this class serializable? |
get_lc_namespace |
Get the namespace of the LangChain object. |
lc_id |
Return a unique identifier for this class for serialization purposes. |
to_json |
Serialize the |
to_json_not_implemented |
Serialize a "not implemented" object. |
configurable_fields |
Configure particular |
configurable_alternatives |
Configure alternatives for |
raise_callback_manager_deprecation |
Raise deprecation warning if callback_manager is used. |
set_verbose |
Set the chain verbosity. |
__call__ |
Execute the chain. |
acall |
Asynchronously execute the chain. |
prep_outputs |
Validate and prepare chain outputs, and save info about this run to memory. |
aprep_outputs |
Validate and prepare chain outputs, and save info about this run to memory. |
prep_inputs |
Prepare chain inputs, including adding inputs from memory. |
aprep_inputs |
Prepare chain inputs, including adding inputs from memory. |
run |
Convenience method for executing chain. |
arun |
Convenience method for executing chain. |
dict |
Dictionary representation of chain. |
save |
Save the chain. |
apply |
Call the chain on all inputs in the list. |
run_mapper
instance-attribute
¶
run_mapper: StringRunMapper
Maps the Run to a dictionary with 'input' and 'prediction' strings.
example_mapper
class-attribute
instance-attribute
¶
example_mapper: StringExampleMapper | None = None
Maps the Example (dataset row) to a dictionary with a 'reference' string.
InputType
property
¶
InputType: type[Input]
Input type.
The type of input this Runnable accepts specified as a type annotation.
| RAISES | DESCRIPTION |
|---|---|
TypeError
|
If the input type cannot be inferred. |
OutputType
property
¶
OutputType: type[Output]
Output Type.
The type of output this Runnable produces specified as a type annotation.
| RAISES | DESCRIPTION |
|---|---|
TypeError
|
If the output type cannot be inferred. |
input_schema
property
¶
The type of input this Runnable accepts specified as a Pydantic model.
output_schema
property
¶
Output schema.
The type of output this Runnable produces specified as a Pydantic model.
config_specs
property
¶
config_specs: list[ConfigurableFieldSpec]
List configurable fields for this Runnable.
lc_secrets
property
¶
A map of constructor argument names to secret ids.
For example, {"openai_api_key": "OPENAI_API_KEY"}
lc_attributes
property
¶
lc_attributes: dict
List of attribute names that should be included in the serialized kwargs.
These attributes must be accepted by the constructor.
Default is an empty dictionary.
memory
class-attribute
instance-attribute
¶
Optional memory object. Memory is a class that gets called at the start and at the end of every chain. At the start, memory loads variables and passes them along in the chain. At the end, it saves any returned variables. There are many different types of memory - please see memory docs for the full catalog.
callbacks
class-attribute
instance-attribute
¶
callbacks: Callbacks = Field(default=None, exclude=True)
Optional list of callback handlers (or callback manager). Callback handlers are called throughout the lifecycle of a call to a chain, starting with on_chain_start, ending with on_chain_end or on_chain_error. Each custom chain can optionally call additional callback methods, see Callback docs for full details.
verbose
class-attribute
instance-attribute
¶
Whether or not run in verbose mode. In verbose mode, some intermediate logs
will be printed to the console. Defaults to the global verbose value,
accessible via langchain.globals.get_verbose().
tags
class-attribute
instance-attribute
¶
Optional list of tags associated with the chain.
These tags will be associated with each call to this chain,
and passed as arguments to the handlers defined in callbacks.
You can use these to eg identify a specific instance of a chain with its use case.
metadata
class-attribute
instance-attribute
¶
Optional metadata associated with the chain.
This metadata will be associated with each call to this chain,
and passed as arguments to the handlers defined in callbacks.
You can use these to eg identify a specific instance of a chain with its use case.
callback_manager
class-attribute
instance-attribute
¶
callback_manager: BaseCallbackManager | None = Field(default=None, exclude=True)
[DEPRECATED] Use callbacks instead.
evaluate_run
¶
evaluate_run(
run: Run, example: Example | None = None, evaluator_run_id: UUID | None = None
) -> EvaluationResult
Evaluate an example.
aevaluate_run
async
¶
aevaluate_run(
run: Run, example: Example | None = None, evaluator_run_id: UUID | None = None
) -> EvaluationResult
Evaluate an example.
from_run_and_data_type
classmethod
¶
from_run_and_data_type(
evaluator: StringEvaluator,
run_type: str,
data_type: DataType,
input_key: str | None = None,
prediction_key: str | None = None,
reference_key: str | None = None,
tags: list[str] | None = None,
) -> StringRunEvaluatorChain
Create a StringRunEvaluatorChain.
Create a StringRunEvaluatorChain from an evaluator and the run and dataset types.
This method provides an easy way to instantiate a StringRunEvaluatorChain, by taking an evaluator and information about the type of run and the data. The method supports LLM and chain runs.
| PARAMETER | DESCRIPTION |
|---|---|
evaluator
|
The string evaluator to use.
TYPE:
|
run_type
|
The type of run being evaluated. Supported types are LLM and Chain.
TYPE:
|
data_type
|
The type of dataset used in the run.
TYPE:
|
input_key
|
The key used to map the input from the run.
TYPE:
|
prediction_key
|
The key used to map the prediction from the run.
TYPE:
|
reference_key
|
The key used to map the reference from the dataset.
TYPE:
|
tags
|
List of tags to attach to the evaluation chain. |
| RETURNS | DESCRIPTION |
|---|---|
StringRunEvaluatorChain
|
The instantiated evaluation chain. |
get_name
¶
get_input_schema
¶
get_input_schema(config: RunnableConfig | None = None) -> type[BaseModel]
Get a Pydantic model that can be used to validate input to the Runnable.
Runnable objects that leverage the configurable_fields and
configurable_alternatives methods will have a dynamic input schema that
depends on which configuration the Runnable is invoked with.
This method allows to get an input schema for a specific configuration.
| PARAMETER | DESCRIPTION |
|---|---|
config
|
A config to use when generating the schema.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
type[BaseModel]
|
A Pydantic model that can be used to validate input. |
get_input_jsonschema
¶
get_input_jsonschema(config: RunnableConfig | None = None) -> dict[str, Any]
Get a JSON schema that represents the input to the Runnable.
| PARAMETER | DESCRIPTION |
|---|---|
config
|
A config to use when generating the schema.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
dict[str, Any]
|
A JSON schema that represents the input to the |
Example
Added in version 0.3.0
get_output_schema
¶
get_output_schema(config: RunnableConfig | None = None) -> type[BaseModel]
Get a Pydantic model that can be used to validate output to the Runnable.
Runnable objects that leverage the configurable_fields and
configurable_alternatives methods will have a dynamic output schema that
depends on which configuration the Runnable is invoked with.
This method allows to get an output schema for a specific configuration.
| PARAMETER | DESCRIPTION |
|---|---|
config
|
A config to use when generating the schema.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
type[BaseModel]
|
A Pydantic model that can be used to validate output. |
get_output_jsonschema
¶
get_output_jsonschema(config: RunnableConfig | None = None) -> dict[str, Any]
Get a JSON schema that represents the output of the Runnable.
| PARAMETER | DESCRIPTION |
|---|---|
config
|
A config to use when generating the schema.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
dict[str, Any]
|
A JSON schema that represents the output of the |
Example
Added in version 0.3.0
config_schema
¶
The type of config this Runnable accepts specified as a Pydantic model.
To mark a field as configurable, see the configurable_fields
and configurable_alternatives methods.
| PARAMETER | DESCRIPTION |
|---|---|
include
|
A list of fields to include in the config schema. |
| RETURNS | DESCRIPTION |
|---|---|
type[BaseModel]
|
A Pydantic model that can be used to validate config. |
get_config_jsonschema
¶
get_graph
¶
get_graph(config: RunnableConfig | None = None) -> Graph
Return a graph representation of this Runnable.
get_prompts
¶
get_prompts(config: RunnableConfig | None = None) -> list[BasePromptTemplate]
Return a list of prompts used by this Runnable.
__or__
¶
__or__(
other: Runnable[Any, Other]
| Callable[[Iterator[Any]], Iterator[Other]]
| Callable[[AsyncIterator[Any]], AsyncIterator[Other]]
| Callable[[Any], Other]
| Mapping[str, Runnable[Any, Other] | Callable[[Any], Other] | Any],
) -> RunnableSerializable[Input, Other]
Runnable "or" operator.
Compose this Runnable with another object to create a
RunnableSequence.
| PARAMETER | DESCRIPTION |
|---|---|
other
|
Another
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
RunnableSerializable[Input, Other]
|
A new |
__ror__
¶
__ror__(
other: Runnable[Other, Any]
| Callable[[Iterator[Other]], Iterator[Any]]
| Callable[[AsyncIterator[Other]], AsyncIterator[Any]]
| Callable[[Other], Any]
| Mapping[str, Runnable[Other, Any] | Callable[[Other], Any] | Any],
) -> RunnableSerializable[Other, Output]
Runnable "reverse-or" operator.
Compose this Runnable with another object to create a
RunnableSequence.
| PARAMETER | DESCRIPTION |
|---|---|
other
|
Another
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
RunnableSerializable[Other, Output]
|
A new |
pipe
¶
pipe(
*others: Runnable[Any, Other] | Callable[[Any], Other], name: str | None = None
) -> RunnableSerializable[Input, Other]
Pipe Runnable objects.
Compose this Runnable with Runnable-like objects to make a
RunnableSequence.
Equivalent to RunnableSequence(self, *others) or self | others[0] | ...
Example
from langchain_core.runnables import RunnableLambda
def add_one(x: int) -> int:
return x + 1
def mul_two(x: int) -> int:
return x * 2
runnable_1 = RunnableLambda(add_one)
runnable_2 = RunnableLambda(mul_two)
sequence = runnable_1.pipe(runnable_2)
# Or equivalently:
# sequence = runnable_1 | runnable_2
# sequence = RunnableSequence(first=runnable_1, last=runnable_2)
sequence.invoke(1)
await sequence.ainvoke(1)
# -> 4
sequence.batch([1, 2, 3])
await sequence.abatch([1, 2, 3])
# -> [4, 6, 8]
| PARAMETER | DESCRIPTION |
|---|---|
*others
|
Other
TYPE:
|
name
|
An optional name for the resulting
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
RunnableSerializable[Input, Other]
|
A new |
pick
¶
Pick keys from the output dict of this Runnable.
Pick a single key:
import json
from langchain_core.runnables import RunnableLambda, RunnableMap
as_str = RunnableLambda(str)
as_json = RunnableLambda(json.loads)
chain = RunnableMap(str=as_str, json=as_json)
chain.invoke("[1, 2, 3]")
# -> {"str": "[1, 2, 3]", "json": [1, 2, 3]}
json_only_chain = chain.pick("json")
json_only_chain.invoke("[1, 2, 3]")
# -> [1, 2, 3]
Pick a list of keys:
from typing import Any
import json
from langchain_core.runnables import RunnableLambda, RunnableMap
as_str = RunnableLambda(str)
as_json = RunnableLambda(json.loads)
def as_bytes(x: Any) -> bytes:
return bytes(x, "utf-8")
chain = RunnableMap(str=as_str, json=as_json, bytes=RunnableLambda(as_bytes))
chain.invoke("[1, 2, 3]")
# -> {"str": "[1, 2, 3]", "json": [1, 2, 3], "bytes": b"[1, 2, 3]"}
json_and_bytes_chain = chain.pick(["json", "bytes"])
json_and_bytes_chain.invoke("[1, 2, 3]")
# -> {"json": [1, 2, 3], "bytes": b"[1, 2, 3]"}
| PARAMETER | DESCRIPTION |
|---|---|
keys
|
A key or list of keys to pick from the output dict. |
| RETURNS | DESCRIPTION |
|---|---|
RunnableSerializable[Any, Any]
|
a new |
assign
¶
assign(
**kwargs: Runnable[dict[str, Any], Any]
| Callable[[dict[str, Any]], Any]
| Mapping[str, Runnable[dict[str, Any], Any] | Callable[[dict[str, Any]], Any]],
) -> RunnableSerializable[Any, Any]
Assigns new fields to the dict output of this Runnable.
from langchain_community.llms.fake import FakeStreamingListLLM
from langchain_core.output_parsers import StrOutputParser
from langchain_core.prompts import SystemMessagePromptTemplate
from langchain_core.runnables import Runnable
from operator import itemgetter
prompt = (
SystemMessagePromptTemplate.from_template("You are a nice assistant.")
+ "{question}"
)
model = FakeStreamingListLLM(responses=["foo-lish"])
chain: Runnable = prompt | model | {"str": StrOutputParser()}
chain_with_assign = chain.assign(hello=itemgetter("str") | model)
print(chain_with_assign.input_schema.model_json_schema())
# {'title': 'PromptInput', 'type': 'object', 'properties':
{'question': {'title': 'Question', 'type': 'string'}}}
print(chain_with_assign.output_schema.model_json_schema())
# {'title': 'RunnableSequenceOutput', 'type': 'object', 'properties':
{'str': {'title': 'Str',
'type': 'string'}, 'hello': {'title': 'Hello', 'type': 'string'}}}
| PARAMETER | DESCRIPTION |
|---|---|
**kwargs
|
A mapping of keys to
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
RunnableSerializable[Any, Any]
|
A new |
invoke
¶
invoke(
input: dict[str, Any], config: RunnableConfig | None = None, **kwargs: Any
) -> dict[str, Any]
Transform a single input into an output.
| PARAMETER | DESCRIPTION |
|---|---|
input
|
The input to the
TYPE:
|
config
|
A config to use when invoking the
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
Output
|
The output of the |
ainvoke
async
¶
ainvoke(
input: dict[str, Any], config: RunnableConfig | None = None, **kwargs: Any
) -> dict[str, Any]
Transform a single input into an output.
| PARAMETER | DESCRIPTION |
|---|---|
input
|
The input to the
TYPE:
|
config
|
A config to use when invoking the
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
Output
|
The output of the |
batch
¶
batch(
inputs: list[Input],
config: RunnableConfig | list[RunnableConfig] | None = None,
*,
return_exceptions: bool = False,
**kwargs: Any | None,
) -> list[Output]
Default implementation runs invoke in parallel using a thread pool executor.
The default implementation of batch works well for IO bound runnables.
Subclasses must override this method if they can batch more efficiently;
e.g., if the underlying Runnable uses an API which supports a batch mode.
| PARAMETER | DESCRIPTION |
|---|---|
inputs
|
A list of inputs to the
TYPE:
|
config
|
A config to use when invoking the
TYPE:
|
return_exceptions
|
Whether to return exceptions instead of raising them.
TYPE:
|
**kwargs
|
Additional keyword arguments to pass to the
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
list[Output]
|
A list of outputs from the |
batch_as_completed
¶
batch_as_completed(
inputs: Sequence[Input],
config: RunnableConfig | Sequence[RunnableConfig] | None = None,
*,
return_exceptions: bool = False,
**kwargs: Any | None,
) -> Iterator[tuple[int, Output | Exception]]
Run invoke in parallel on a list of inputs.
Yields results as they complete.
| PARAMETER | DESCRIPTION |
|---|---|
inputs
|
A list of inputs to the
TYPE:
|
config
|
A config to use when invoking the
TYPE:
|
return_exceptions
|
Whether to return exceptions instead of raising them.
TYPE:
|
**kwargs
|
Additional keyword arguments to pass to the
TYPE:
|
| YIELDS | DESCRIPTION |
|---|---|
tuple[int, Output | Exception]
|
Tuples of the index of the input and the output from the |
abatch
async
¶
abatch(
inputs: list[Input],
config: RunnableConfig | list[RunnableConfig] | None = None,
*,
return_exceptions: bool = False,
**kwargs: Any | None,
) -> list[Output]
Default implementation runs ainvoke in parallel using asyncio.gather.
The default implementation of batch works well for IO bound runnables.
Subclasses must override this method if they can batch more efficiently;
e.g., if the underlying Runnable uses an API which supports a batch mode.
| PARAMETER | DESCRIPTION |
|---|---|
inputs
|
A list of inputs to the
TYPE:
|
config
|
A config to use when invoking the
TYPE:
|
return_exceptions
|
Whether to return exceptions instead of raising them.
TYPE:
|
**kwargs
|
Additional keyword arguments to pass to the
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
list[Output]
|
A list of outputs from the |
abatch_as_completed
async
¶
abatch_as_completed(
inputs: Sequence[Input],
config: RunnableConfig | Sequence[RunnableConfig] | None = None,
*,
return_exceptions: bool = False,
**kwargs: Any | None,
) -> AsyncIterator[tuple[int, Output | Exception]]
Run ainvoke in parallel on a list of inputs.
Yields results as they complete.
| PARAMETER | DESCRIPTION |
|---|---|
inputs
|
A list of inputs to the
TYPE:
|
config
|
A config to use when invoking the
TYPE:
|
return_exceptions
|
Whether to return exceptions instead of raising them.
TYPE:
|
**kwargs
|
Additional keyword arguments to pass to the
TYPE:
|
| YIELDS | DESCRIPTION |
|---|---|
AsyncIterator[tuple[int, Output | Exception]]
|
A tuple of the index of the input and the output from the |
stream
¶
stream(
input: Input, config: RunnableConfig | None = None, **kwargs: Any | None
) -> Iterator[Output]
Default implementation of stream, which calls invoke.
Subclasses must override this method if they support streaming output.
| PARAMETER | DESCRIPTION |
|---|---|
input
|
The input to the
TYPE:
|
config
|
The config to use for the
TYPE:
|
**kwargs
|
Additional keyword arguments to pass to the
TYPE:
|
| YIELDS | DESCRIPTION |
|---|---|
Output
|
The output of the |
astream
async
¶
astream(
input: Input, config: RunnableConfig | None = None, **kwargs: Any | None
) -> AsyncIterator[Output]
Default implementation of astream, which calls ainvoke.
Subclasses must override this method if they support streaming output.
| PARAMETER | DESCRIPTION |
|---|---|
input
|
The input to the
TYPE:
|
config
|
The config to use for the
TYPE:
|
**kwargs
|
Additional keyword arguments to pass to the
TYPE:
|
| YIELDS | DESCRIPTION |
|---|---|
AsyncIterator[Output]
|
The output of the |
astream_log
async
¶
astream_log(
input: Any,
config: RunnableConfig | None = None,
*,
diff: bool = True,
with_streamed_output_list: bool = True,
include_names: Sequence[str] | None = None,
include_types: Sequence[str] | None = None,
include_tags: Sequence[str] | None = None,
exclude_names: Sequence[str] | None = None,
exclude_types: Sequence[str] | None = None,
exclude_tags: Sequence[str] | None = None,
**kwargs: Any,
) -> AsyncIterator[RunLogPatch] | AsyncIterator[RunLog]
Stream all output from a Runnable, as reported to the callback system.
This includes all inner runs of LLMs, Retrievers, Tools, etc.
Output is streamed as Log objects, which include a list of Jsonpatch ops that describe how the state of the run has changed in each step, and the final state of the run.
The Jsonpatch ops can be applied in order to construct state.
| PARAMETER | DESCRIPTION |
|---|---|
input
|
The input to the
TYPE:
|
config
|
The config to use for the
TYPE:
|
diff
|
Whether to yield diffs between each step or the current state.
TYPE:
|
with_streamed_output_list
|
Whether to yield the
TYPE:
|
include_names
|
Only include logs with these names. |
include_types
|
Only include logs with these types. |
include_tags
|
Only include logs with these tags. |
exclude_names
|
Exclude logs with these names. |
exclude_types
|
Exclude logs with these types. |
exclude_tags
|
Exclude logs with these tags. |
**kwargs
|
Additional keyword arguments to pass to the
TYPE:
|
| YIELDS | DESCRIPTION |
|---|---|
AsyncIterator[RunLogPatch] | AsyncIterator[RunLog]
|
A |
astream_events
async
¶
astream_events(
input: Any,
config: RunnableConfig | None = None,
*,
version: Literal["v1", "v2"] = "v2",
include_names: Sequence[str] | None = None,
include_types: Sequence[str] | None = None,
include_tags: Sequence[str] | None = None,
exclude_names: Sequence[str] | None = None,
exclude_types: Sequence[str] | None = None,
exclude_tags: Sequence[str] | None = None,
**kwargs: Any,
) -> AsyncIterator[StreamEvent]
Generate a stream of events.
Use to create an iterator over StreamEvent that provide real-time information
about the progress of the Runnable, including StreamEvent from intermediate
results.
A StreamEvent is a dictionary with the following schema:
event: Event names are of the format:on_[runnable_type]_(start|stream|end).name: The name of theRunnablethat generated the event.run_id: Randomly generated ID associated with the given execution of theRunnablethat emitted the event. A childRunnablethat gets invoked as part of the execution of a parentRunnableis assigned its own unique ID.parent_ids: The IDs of the parent runnables that generated the event. The rootRunnablewill have an empty list. The order of the parent IDs is from the root to the immediate parent. Only available for v2 version of the API. The v1 version of the API will return an empty list.tags: The tags of theRunnablethat generated the event.metadata: The metadata of theRunnablethat generated the event.data: The data associated with the event. The contents of this field depend on the type of event. See the table below for more details.
Below is a table that illustrates some events that might be emitted by various chains. Metadata fields have been omitted from the table for brevity. Chain definitions have been included after the table.
Note
This reference table is for the v2 version of the schema.
| event | name | chunk | input | output |
|---|---|---|---|---|
on_chat_model_start |
'[model name]' |
{"messages": [[SystemMessage, HumanMessage]]} |
||
on_chat_model_stream |
'[model name]' |
AIMessageChunk(content="hello") |
||
on_chat_model_end |
'[model name]' |
{"messages": [[SystemMessage, HumanMessage]]} |
AIMessageChunk(content="hello world") |
|
on_llm_start |
'[model name]' |
{'input': 'hello'} |
||
on_llm_stream |
'[model name]' |
'Hello' |
||
on_llm_end |
'[model name]' |
'Hello human!' |
||
on_chain_start |
'format_docs' |
|||
on_chain_stream |
'format_docs' |
'hello world!, goodbye world!' |
||
on_chain_end |
'format_docs' |
[Document(...)] |
'hello world!, goodbye world!' |
|
on_tool_start |
'some_tool' |
{"x": 1, "y": "2"} |
||
on_tool_end |
'some_tool' |
{"x": 1, "y": "2"} |
||
on_retriever_start |
'[retriever name]' |
{"query": "hello"} |
||
on_retriever_end |
'[retriever name]' |
{"query": "hello"} |
[Document(...), ..] |
|
on_prompt_start |
'[template_name]' |
{"question": "hello"} |
||
on_prompt_end |
'[template_name]' |
{"question": "hello"} |
ChatPromptValue(messages: [SystemMessage, ...]) |
In addition to the standard events, users can also dispatch custom events (see example below).
Custom events will be only be surfaced with in the v2 version of the API!
A custom event has following format:
| Attribute | Type | Description |
|---|---|---|
name |
str |
A user defined name for the event. |
data |
Any |
The data associated with the event. This can be anything, though we suggest making it JSON serializable. |
Here are declarations associated with the standard events shown above:
format_docs:
def format_docs(docs: list[Document]) -> str:
'''Format the docs.'''
return ", ".join([doc.page_content for doc in docs])
format_docs = RunnableLambda(format_docs)
some_tool:
prompt:
template = ChatPromptTemplate.from_messages(
[
("system", "You are Cat Agent 007"),
("human", "{question}"),
]
).with_config({"run_name": "my_template", "tags": ["my_template"]})
For instance:
from langchain_core.runnables import RunnableLambda
async def reverse(s: str) -> str:
return s[::-1]
chain = RunnableLambda(func=reverse)
events = [event async for event in chain.astream_events("hello", version="v2")]
# Will produce the following events
# (run_id, and parent_ids has been omitted for brevity):
[
{
"data": {"input": "hello"},
"event": "on_chain_start",
"metadata": {},
"name": "reverse",
"tags": [],
},
{
"data": {"chunk": "olleh"},
"event": "on_chain_stream",
"metadata": {},
"name": "reverse",
"tags": [],
},
{
"data": {"output": "olleh"},
"event": "on_chain_end",
"metadata": {},
"name": "reverse",
"tags": [],
},
]
from langchain_core.callbacks.manager import (
adispatch_custom_event,
)
from langchain_core.runnables import RunnableLambda, RunnableConfig
import asyncio
async def slow_thing(some_input: str, config: RunnableConfig) -> str:
"""Do something that takes a long time."""
await asyncio.sleep(1) # Placeholder for some slow operation
await adispatch_custom_event(
"progress_event",
{"message": "Finished step 1 of 3"},
config=config # Must be included for python < 3.10
)
await asyncio.sleep(1) # Placeholder for some slow operation
await adispatch_custom_event(
"progress_event",
{"message": "Finished step 2 of 3"},
config=config # Must be included for python < 3.10
)
await asyncio.sleep(1) # Placeholder for some slow operation
return "Done"
slow_thing = RunnableLambda(slow_thing)
async for event in slow_thing.astream_events("some_input", version="v2"):
print(event)
| PARAMETER | DESCRIPTION |
|---|---|
input
|
The input to the
TYPE:
|
config
|
The config to use for the
TYPE:
|
version
|
The version of the schema to use either
TYPE:
|
include_names
|
Only include events from |
include_types
|
Only include events from |
include_tags
|
Only include events from |
exclude_names
|
Exclude events from |
exclude_types
|
Exclude events from |
exclude_tags
|
Exclude events from |
**kwargs
|
Additional keyword arguments to pass to the
TYPE:
|
| YIELDS | DESCRIPTION |
|---|---|
AsyncIterator[StreamEvent]
|
An async stream of |
| RAISES | DESCRIPTION |
|---|---|
NotImplementedError
|
If the version is not |
transform
¶
transform(
input: Iterator[Input], config: RunnableConfig | None = None, **kwargs: Any | None
) -> Iterator[Output]
Transform inputs to outputs.
Default implementation of transform, which buffers input and calls astream.
Subclasses must override this method if they can start producing output while input is still being generated.
| PARAMETER | DESCRIPTION |
|---|---|
input
|
An iterator of inputs to the
TYPE:
|
config
|
The config to use for the
TYPE:
|
**kwargs
|
Additional keyword arguments to pass to the
TYPE:
|
| YIELDS | DESCRIPTION |
|---|---|
Output
|
The output of the |
atransform
async
¶
atransform(
input: AsyncIterator[Input],
config: RunnableConfig | None = None,
**kwargs: Any | None,
) -> AsyncIterator[Output]
Transform inputs to outputs.
Default implementation of atransform, which buffers input and calls astream.
Subclasses must override this method if they can start producing output while input is still being generated.
| PARAMETER | DESCRIPTION |
|---|---|
input
|
An async iterator of inputs to the
TYPE:
|
config
|
The config to use for the
TYPE:
|
**kwargs
|
Additional keyword arguments to pass to the
TYPE:
|
| YIELDS | DESCRIPTION |
|---|---|
AsyncIterator[Output]
|
The output of the |
bind
¶
Bind arguments to a Runnable, returning a new Runnable.
Useful when a Runnable in a chain requires an argument that is not
in the output of the previous Runnable or included in the user input.
| PARAMETER | DESCRIPTION |
|---|---|
**kwargs
|
The arguments to bind to the
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
Runnable[Input, Output]
|
A new |
Example
from langchain_ollama import ChatOllama
from langchain_core.output_parsers import StrOutputParser
model = ChatOllama(model="llama3.1")
# Without bind
chain = model | StrOutputParser()
chain.invoke("Repeat quoted words exactly: 'One two three four five.'")
# Output is 'One two three four five.'
# With bind
chain = model.bind(stop=["three"]) | StrOutputParser()
chain.invoke("Repeat quoted words exactly: 'One two three four five.'")
# Output is 'One two'
with_config
¶
with_config(
config: RunnableConfig | None = None, **kwargs: Any
) -> Runnable[Input, Output]
Bind config to a Runnable, returning a new Runnable.
| PARAMETER | DESCRIPTION |
|---|---|
config
|
The config to bind to the
TYPE:
|
**kwargs
|
Additional keyword arguments to pass to the
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
Runnable[Input, Output]
|
A new |
with_listeners
¶
with_listeners(
*,
on_start: Callable[[Run], None]
| Callable[[Run, RunnableConfig], None]
| None = None,
on_end: Callable[[Run], None] | Callable[[Run, RunnableConfig], None] | None = None,
on_error: Callable[[Run], None]
| Callable[[Run, RunnableConfig], None]
| None = None,
) -> Runnable[Input, Output]
Bind lifecycle listeners to a Runnable, returning a new Runnable.
The Run object contains information about the run, including its id,
type, input, output, error, start_time, end_time, and
any tags or metadata added to the run.
| PARAMETER | DESCRIPTION |
|---|---|
on_start
|
Called before the
TYPE:
|
on_end
|
Called after the
TYPE:
|
on_error
|
Called if the
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
Runnable[Input, Output]
|
A new |
Example
from langchain_core.runnables import RunnableLambda
from langchain_core.tracers.schemas import Run
import time
def test_runnable(time_to_sleep: int):
time.sleep(time_to_sleep)
def fn_start(run_obj: Run):
print("start_time:", run_obj.start_time)
def fn_end(run_obj: Run):
print("end_time:", run_obj.end_time)
chain = RunnableLambda(test_runnable).with_listeners(
on_start=fn_start, on_end=fn_end
)
chain.invoke(2)
with_alisteners
¶
with_alisteners(
*,
on_start: AsyncListener | None = None,
on_end: AsyncListener | None = None,
on_error: AsyncListener | None = None,
) -> Runnable[Input, Output]
Bind async lifecycle listeners to a Runnable.
Returns a new Runnable.
The Run object contains information about the run, including its id,
type, input, output, error, start_time, end_time, and
any tags or metadata added to the run.
| PARAMETER | DESCRIPTION |
|---|---|
on_start
|
Called asynchronously before the
TYPE:
|
on_end
|
Called asynchronously after the
TYPE:
|
on_error
|
Called asynchronously if the
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
Runnable[Input, Output]
|
A new |
Example
from langchain_core.runnables import RunnableLambda, Runnable
from datetime import datetime, timezone
import time
import asyncio
def format_t(timestamp: float) -> str:
return datetime.fromtimestamp(timestamp, tz=timezone.utc).isoformat()
async def test_runnable(time_to_sleep: int):
print(f"Runnable[{time_to_sleep}s]: starts at {format_t(time.time())}")
await asyncio.sleep(time_to_sleep)
print(f"Runnable[{time_to_sleep}s]: ends at {format_t(time.time())}")
async def fn_start(run_obj: Runnable):
print(f"on start callback starts at {format_t(time.time())}")
await asyncio.sleep(3)
print(f"on start callback ends at {format_t(time.time())}")
async def fn_end(run_obj: Runnable):
print(f"on end callback starts at {format_t(time.time())}")
await asyncio.sleep(2)
print(f"on end callback ends at {format_t(time.time())}")
runnable = RunnableLambda(test_runnable).with_alisteners(
on_start=fn_start,
on_end=fn_end
)
async def concurrent_runs():
await asyncio.gather(runnable.ainvoke(2), runnable.ainvoke(3))
asyncio.run(concurrent_runs())
Result:
on start callback starts at 2025-03-01T07:05:22.875378+00:00
on start callback starts at 2025-03-01T07:05:22.875495+00:00
on start callback ends at 2025-03-01T07:05:25.878862+00:00
on start callback ends at 2025-03-01T07:05:25.878947+00:00
Runnable[2s]: starts at 2025-03-01T07:05:25.879392+00:00
Runnable[3s]: starts at 2025-03-01T07:05:25.879804+00:00
Runnable[2s]: ends at 2025-03-01T07:05:27.881998+00:00
on end callback starts at 2025-03-01T07:05:27.882360+00:00
Runnable[3s]: ends at 2025-03-01T07:05:28.881737+00:00
on end callback starts at 2025-03-01T07:05:28.882428+00:00
on end callback ends at 2025-03-01T07:05:29.883893+00:00
on end callback ends at 2025-03-01T07:05:30.884831+00:00
with_types
¶
with_types(
*, input_type: type[Input] | None = None, output_type: type[Output] | None = None
) -> Runnable[Input, Output]
Bind input and output types to a Runnable, returning a new Runnable.
| PARAMETER | DESCRIPTION |
|---|---|
input_type
|
The input type to bind to the
TYPE:
|
output_type
|
The output type to bind to the
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
Runnable[Input, Output]
|
A new |
with_retry
¶
with_retry(
*,
retry_if_exception_type: tuple[type[BaseException], ...] = (Exception,),
wait_exponential_jitter: bool = True,
exponential_jitter_params: ExponentialJitterParams | None = None,
stop_after_attempt: int = 3,
) -> Runnable[Input, Output]
Create a new Runnable that retries the original Runnable on exceptions.
| PARAMETER | DESCRIPTION |
|---|---|
retry_if_exception_type
|
A tuple of exception types to retry on.
TYPE:
|
wait_exponential_jitter
|
Whether to add jitter to the wait time between retries.
TYPE:
|
stop_after_attempt
|
The maximum number of attempts to make before giving up.
TYPE:
|
exponential_jitter_params
|
Parameters for
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
Runnable[Input, Output]
|
A new Runnable that retries the original Runnable on exceptions. |
Example
from langchain_core.runnables import RunnableLambda
count = 0
def _lambda(x: int) -> None:
global count
count = count + 1
if x == 1:
raise ValueError("x is 1")
else:
pass
runnable = RunnableLambda(_lambda)
try:
runnable.with_retry(
stop_after_attempt=2,
retry_if_exception_type=(ValueError,),
).invoke(1)
except ValueError:
pass
assert count == 2
map
¶
with_fallbacks
¶
with_fallbacks(
fallbacks: Sequence[Runnable[Input, Output]],
*,
exceptions_to_handle: tuple[type[BaseException], ...] = (Exception,),
exception_key: str | None = None,
) -> RunnableWithFallbacks[Input, Output]
Add fallbacks to a Runnable, returning a new Runnable.
The new Runnable will try the original Runnable, and then each fallback
in order, upon failures.
| PARAMETER | DESCRIPTION |
|---|---|
fallbacks
|
A sequence of runnables to try if the original |
exceptions_to_handle
|
A tuple of exception types to handle.
TYPE:
|
exception_key
|
If
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
RunnableWithFallbacks[Input, Output]
|
A new |
Example
from typing import Iterator
from langchain_core.runnables import RunnableGenerator
def _generate_immediate_error(input: Iterator) -> Iterator[str]:
raise ValueError()
yield ""
def _generate(input: Iterator) -> Iterator[str]:
yield from "foo bar"
runnable = RunnableGenerator(_generate_immediate_error).with_fallbacks(
[RunnableGenerator(_generate)]
)
print("".join(runnable.stream({}))) # foo bar
| PARAMETER | DESCRIPTION |
|---|---|
fallbacks
|
A sequence of runnables to try if the original |
exceptions_to_handle
|
A tuple of exception types to handle.
TYPE:
|
exception_key
|
If
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
RunnableWithFallbacks[Input, Output]
|
A new |
as_tool
¶
as_tool(
args_schema: type[BaseModel] | None = None,
*,
name: str | None = None,
description: str | None = None,
arg_types: dict[str, type] | None = None,
) -> BaseTool
Create a BaseTool from a Runnable.
as_tool will instantiate a BaseTool with a name, description, and
args_schema from a Runnable. Where possible, schemas are inferred
from runnable.get_input_schema. Alternatively (e.g., if the
Runnable takes a dict as input and the specific dict keys are not typed),
the schema can be specified directly with args_schema. You can also
pass arg_types to just specify the required arguments and their types.
| PARAMETER | DESCRIPTION |
|---|---|
args_schema
|
The schema for the tool. |
name
|
The name of the tool.
TYPE:
|
description
|
The description of the tool.
TYPE:
|
arg_types
|
A dictionary of argument names to types. |
| RETURNS | DESCRIPTION |
|---|---|
BaseTool
|
A |
Typed dict input:
from typing_extensions import TypedDict
from langchain_core.runnables import RunnableLambda
class Args(TypedDict):
a: int
b: list[int]
def f(x: Args) -> str:
return str(x["a"] * max(x["b"]))
runnable = RunnableLambda(f)
as_tool = runnable.as_tool()
as_tool.invoke({"a": 3, "b": [1, 2]})
dict input, specifying schema via args_schema:
from typing import Any
from pydantic import BaseModel, Field
from langchain_core.runnables import RunnableLambda
def f(x: dict[str, Any]) -> str:
return str(x["a"] * max(x["b"]))
class FSchema(BaseModel):
"""Apply a function to an integer and list of integers."""
a: int = Field(..., description="Integer")
b: list[int] = Field(..., description="List of ints")
runnable = RunnableLambda(f)
as_tool = runnable.as_tool(FSchema)
as_tool.invoke({"a": 3, "b": [1, 2]})
dict input, specifying schema via arg_types:
from typing import Any
from langchain_core.runnables import RunnableLambda
def f(x: dict[str, Any]) -> str:
return str(x["a"] * max(x["b"]))
runnable = RunnableLambda(f)
as_tool = runnable.as_tool(arg_types={"a": int, "b": list[int]})
as_tool.invoke({"a": 3, "b": [1, 2]})
String input:
is_lc_serializable
classmethod
¶
is_lc_serializable() -> bool
Is this class serializable?
By design, even if a class inherits from Serializable, it is not serializable
by default. This is to prevent accidental serialization of objects that should
not be serialized.
| RETURNS | DESCRIPTION |
|---|---|
bool
|
Whether the class is serializable. Default is |
get_lc_namespace
classmethod
¶
lc_id
classmethod
¶
Return a unique identifier for this class for serialization purposes.
The unique identifier is a list of strings that describes the path to the object.
For example, for the class langchain.llms.openai.OpenAI, the id is
["langchain", "llms", "openai", "OpenAI"].
to_json
¶
Serialize the Runnable to JSON.
| RETURNS | DESCRIPTION |
|---|---|
SerializedConstructor | SerializedNotImplemented
|
A JSON-serializable representation of the |
to_json_not_implemented
¶
Serialize a "not implemented" object.
| RETURNS | DESCRIPTION |
|---|---|
SerializedNotImplemented
|
|
configurable_fields
¶
configurable_fields(
**kwargs: AnyConfigurableField,
) -> RunnableSerializable[Input, Output]
Configure particular Runnable fields at runtime.
| PARAMETER | DESCRIPTION |
|---|---|
**kwargs
|
A dictionary of
TYPE:
|
| RAISES | DESCRIPTION |
|---|---|
ValueError
|
If a configuration key is not found in the |
| RETURNS | DESCRIPTION |
|---|---|
RunnableSerializable[Input, Output]
|
A new |
from langchain_core.runnables import ConfigurableField
from langchain_openai import ChatOpenAI
model = ChatOpenAI(max_tokens=20).configurable_fields(
max_tokens=ConfigurableField(
id="output_token_number",
name="Max tokens in the output",
description="The maximum number of tokens in the output",
)
)
# max_tokens = 20
print("max_tokens_20: ", model.invoke("tell me something about chess").content)
# max_tokens = 200
print(
"max_tokens_200: ",
model.with_config(configurable={"output_token_number": 200})
.invoke("tell me something about chess")
.content,
)
configurable_alternatives
¶
configurable_alternatives(
which: ConfigurableField,
*,
default_key: str = "default",
prefix_keys: bool = False,
**kwargs: Runnable[Input, Output] | Callable[[], Runnable[Input, Output]],
) -> RunnableSerializable[Input, Output]
Configure alternatives for Runnable objects that can be set at runtime.
| PARAMETER | DESCRIPTION |
|---|---|
which
|
The
TYPE:
|
default_key
|
The default key to use if no alternative is selected.
TYPE:
|
prefix_keys
|
Whether to prefix the keys with the
TYPE:
|
**kwargs
|
A dictionary of keys to
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
RunnableSerializable[Input, Output]
|
A new |
from langchain_anthropic import ChatAnthropic
from langchain_core.runnables.utils import ConfigurableField
from langchain_openai import ChatOpenAI
model = ChatAnthropic(
model_name="claude-3-7-sonnet-20250219"
).configurable_alternatives(
ConfigurableField(id="llm"),
default_key="anthropic",
openai=ChatOpenAI(),
)
# uses the default model ChatAnthropic
print(model.invoke("which organization created you?").content)
# uses ChatOpenAI
print(
model.with_config(configurable={"llm": "openai"})
.invoke("which organization created you?")
.content
)
raise_callback_manager_deprecation
classmethod
¶
Raise deprecation warning if callback_manager is used.
set_verbose
classmethod
¶
Set the chain verbosity.
Defaults to the global setting if not specified by the user.
__call__
¶
__call__(
inputs: dict[str, Any] | Any,
return_only_outputs: bool = False,
callbacks: Callbacks = None,
*,
tags: list[str] | None = None,
metadata: dict[str, Any] | None = None,
run_name: str | None = None,
include_run_info: bool = False,
) -> dict[str, Any]
Execute the chain.
| PARAMETER | DESCRIPTION |
|---|---|
inputs
|
Dictionary of inputs, or single input if chain expects
only one param. Should contain all inputs specified in
|
return_only_outputs
|
Whether to return only outputs in the
response. If
TYPE:
|
callbacks
|
Callbacks to use for this chain run. These will be called in addition to callbacks passed to the chain during construction, but only these runtime callbacks will propagate to calls to other objects.
TYPE:
|
tags
|
List of string tags to pass to all callbacks. These will be passed in addition to tags passed to the chain during construction, but only these runtime tags will propagate to calls to other objects. |
metadata
|
Optional metadata associated with the chain. |
run_name
|
Optional name for this run of the chain.
TYPE:
|
include_run_info
|
Whether to include run info in the response. Defaults to False.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
dict[str, Any]
|
A dict of named outputs. Should contain all outputs specified in
|
acall
async
¶
acall(
inputs: dict[str, Any] | Any,
return_only_outputs: bool = False,
callbacks: Callbacks = None,
*,
tags: list[str] | None = None,
metadata: dict[str, Any] | None = None,
run_name: str | None = None,
include_run_info: bool = False,
) -> dict[str, Any]
Asynchronously execute the chain.
| PARAMETER | DESCRIPTION |
|---|---|
inputs
|
Dictionary of inputs, or single input if chain expects
only one param. Should contain all inputs specified in
|
return_only_outputs
|
Whether to return only outputs in the
response. If
TYPE:
|
callbacks
|
Callbacks to use for this chain run. These will be called in addition to callbacks passed to the chain during construction, but only these runtime callbacks will propagate to calls to other objects.
TYPE:
|
tags
|
List of string tags to pass to all callbacks. These will be passed in addition to tags passed to the chain during construction, but only these runtime tags will propagate to calls to other objects. |
metadata
|
Optional metadata associated with the chain. |
run_name
|
Optional name for this run of the chain.
TYPE:
|
include_run_info
|
Whether to include run info in the response. Defaults to False.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
dict[str, Any]
|
A dict of named outputs. Should contain all outputs specified in
|
prep_outputs
¶
prep_outputs(
inputs: dict[str, str], outputs: dict[str, str], return_only_outputs: bool = False
) -> dict[str, str]
Validate and prepare chain outputs, and save info about this run to memory.
| PARAMETER | DESCRIPTION |
|---|---|
inputs
|
Dictionary of chain inputs, including any inputs added by chain memory. |
outputs
|
Dictionary of initial chain outputs. |
return_only_outputs
|
Whether to only return the chain outputs. If
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
dict[str, str]
|
A dict of the final chain outputs. |
aprep_outputs
async
¶
aprep_outputs(
inputs: dict[str, str], outputs: dict[str, str], return_only_outputs: bool = False
) -> dict[str, str]
Validate and prepare chain outputs, and save info about this run to memory.
| PARAMETER | DESCRIPTION |
|---|---|
inputs
|
Dictionary of chain inputs, including any inputs added by chain memory. |
outputs
|
Dictionary of initial chain outputs. |
return_only_outputs
|
Whether to only return the chain outputs. If
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
dict[str, str]
|
A dict of the final chain outputs. |
prep_inputs
¶
Prepare chain inputs, including adding inputs from memory.
| PARAMETER | DESCRIPTION |
|---|---|
inputs
|
Dictionary of raw inputs, or single input if chain expects
only one param. Should contain all inputs specified in
|
| RETURNS | DESCRIPTION |
|---|---|
dict[str, str]
|
A dictionary of all inputs, including those added by the chain's memory. |
aprep_inputs
async
¶
Prepare chain inputs, including adding inputs from memory.
| PARAMETER | DESCRIPTION |
|---|---|
inputs
|
Dictionary of raw inputs, or single input if chain expects
only one param. Should contain all inputs specified in
|
| RETURNS | DESCRIPTION |
|---|---|
dict[str, str]
|
A dictionary of all inputs, including those added by the chain's memory. |
run
¶
run(
*args: Any,
callbacks: Callbacks = None,
tags: list[str] | None = None,
metadata: dict[str, Any] | None = None,
**kwargs: Any,
) -> Any
Convenience method for executing chain.
The main difference between this method and Chain.__call__ is that this
method expects inputs to be passed directly in as positional arguments or
keyword arguments, whereas Chain.__call__ expects a single input dictionary
with all the inputs
| PARAMETER | DESCRIPTION |
|---|---|
*args
|
If the chain expects a single input, it can be passed in as the sole positional argument.
TYPE:
|
callbacks
|
Callbacks to use for this chain run. These will be called in addition to callbacks passed to the chain during construction, but only these runtime callbacks will propagate to calls to other objects.
TYPE:
|
tags
|
List of string tags to pass to all callbacks. These will be passed in addition to tags passed to the chain during construction, but only these runtime tags will propagate to calls to other objects. |
metadata
|
Optional metadata associated with the chain. |
**kwargs
|
If the chain expects multiple inputs, they can be passed in directly as keyword arguments.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
Any
|
The chain output. |
Example
# Suppose we have a single-input chain that takes a 'question' string:
chain.run("What's the temperature in Boise, Idaho?")
# -> "The temperature in Boise is..."
# Suppose we have a multi-input chain that takes a 'question' string
# and 'context' string:
question = "What's the temperature in Boise, Idaho?"
context = "Weather report for Boise, Idaho on 07/03/23..."
chain.run(question=question, context=context)
# -> "The temperature in Boise is..."
arun
async
¶
arun(
*args: Any,
callbacks: Callbacks = None,
tags: list[str] | None = None,
metadata: dict[str, Any] | None = None,
**kwargs: Any,
) -> Any
Convenience method for executing chain.
The main difference between this method and Chain.__call__ is that this
method expects inputs to be passed directly in as positional arguments or
keyword arguments, whereas Chain.__call__ expects a single input dictionary
with all the inputs
| PARAMETER | DESCRIPTION |
|---|---|
*args
|
If the chain expects a single input, it can be passed in as the sole positional argument.
TYPE:
|
callbacks
|
Callbacks to use for this chain run. These will be called in addition to callbacks passed to the chain during construction, but only these runtime callbacks will propagate to calls to other objects.
TYPE:
|
tags
|
List of string tags to pass to all callbacks. These will be passed in addition to tags passed to the chain during construction, but only these runtime tags will propagate to calls to other objects. |
metadata
|
Optional metadata associated with the chain. |
**kwargs
|
If the chain expects multiple inputs, they can be passed in directly as keyword arguments.
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
Any
|
The chain output. |
Example
# Suppose we have a single-input chain that takes a 'question' string:
await chain.arun("What's the temperature in Boise, Idaho?")
# -> "The temperature in Boise is..."
# Suppose we have a multi-input chain that takes a 'question' string
# and 'context' string:
question = "What's the temperature in Boise, Idaho?"
context = "Weather report for Boise, Idaho on 07/03/23..."
await chain.arun(question=question, context=context)
# -> "The temperature in Boise is..."
dict
¶
Dictionary representation of chain.
Expects Chain._chain_type property to be implemented and for memory to be
null.
| PARAMETER | DESCRIPTION |
|---|---|
**kwargs
|
Keyword arguments passed to default
TYPE:
|
| RETURNS | DESCRIPTION |
|---|---|
dict
|
A dictionary representation of the chain. |
save
¶
StringRunMapper
¶
Bases: Serializable
Extract items to evaluate from the run object.
| METHOD | DESCRIPTION |
|---|---|
map |
Maps the Run to a dictionary. |
__call__ |
Maps the Run to a dictionary. |
__init__ |
|
is_lc_serializable |
Is this class serializable? |
get_lc_namespace |
Get the namespace of the LangChain object. |
lc_id |
Return a unique identifier for this class for serialization purposes. |
to_json |
Serialize the object to JSON. |
to_json_not_implemented |
Serialize a "not implemented" object. |
lc_secrets
property
¶
A map of constructor argument names to secret ids.
For example, {"openai_api_key": "OPENAI_API_KEY"}
lc_attributes
property
¶
lc_attributes: dict
List of attribute names that should be included in the serialized kwargs.
These attributes must be accepted by the constructor.
Default is an empty dictionary.
is_lc_serializable
classmethod
¶
is_lc_serializable() -> bool
Is this class serializable?
By design, even if a class inherits from Serializable, it is not serializable
by default. This is to prevent accidental serialization of objects that should
not be serialized.
| RETURNS | DESCRIPTION |
|---|---|
bool
|
Whether the class is serializable. Default is |
get_lc_namespace
classmethod
¶
lc_id
classmethod
¶
Return a unique identifier for this class for serialization purposes.
The unique identifier is a list of strings that describes the path to the object.
For example, for the class langchain.llms.openai.OpenAI, the id is
["langchain", "llms", "openai", "OpenAI"].
to_json
¶
Serialize the object to JSON.
| RAISES | DESCRIPTION |
|---|---|
ValueError
|
If the class has deprecated attributes. |
| RETURNS | DESCRIPTION |
|---|---|
SerializedConstructor | SerializedNotImplemented
|
A JSON serializable object or a |
to_json_not_implemented
¶
Serialize a "not implemented" object.
| RETURNS | DESCRIPTION |
|---|---|
SerializedNotImplemented
|
|
ToolStringRunMapper
¶
Bases: StringRunMapper
Map an input to the tool.
| METHOD | DESCRIPTION |
|---|---|
map |
Maps the Run to a dictionary. |
__init__ |
|
is_lc_serializable |
Is this class serializable? |
get_lc_namespace |
Get the namespace of the LangChain object. |
lc_id |
Return a unique identifier for this class for serialization purposes. |
to_json |
Serialize the object to JSON. |
to_json_not_implemented |
Serialize a "not implemented" object. |
__call__ |
Maps the Run to a dictionary. |
lc_secrets
property
¶
A map of constructor argument names to secret ids.
For example, {"openai_api_key": "OPENAI_API_KEY"}
lc_attributes
property
¶
lc_attributes: dict
List of attribute names that should be included in the serialized kwargs.
These attributes must be accepted by the constructor.
Default is an empty dictionary.
is_lc_serializable
classmethod
¶
is_lc_serializable() -> bool
Is this class serializable?
By design, even if a class inherits from Serializable, it is not serializable
by default. This is to prevent accidental serialization of objects that should
not be serialized.
| RETURNS | DESCRIPTION |
|---|---|
bool
|
Whether the class is serializable. Default is |
get_lc_namespace
classmethod
¶
lc_id
classmethod
¶
Return a unique identifier for this class for serialization purposes.
The unique identifier is a list of strings that describes the path to the object.
For example, for the class langchain.llms.openai.OpenAI, the id is
["langchain", "llms", "openai", "OpenAI"].
to_json
¶
Serialize the object to JSON.
| RAISES | DESCRIPTION |
|---|---|
ValueError
|
If the class has deprecated attributes. |
| RETURNS | DESCRIPTION |
|---|---|
SerializedConstructor | SerializedNotImplemented
|
A JSON serializable object or a |
to_json_not_implemented
¶
Serialize a "not implemented" object.
| RETURNS | DESCRIPTION |
|---|---|
SerializedNotImplemented
|
|
langchain_classic.smith.evaluation.name_generation
¶
| FUNCTION | DESCRIPTION |
|---|---|
random_name |
Generate a random name. |