measuring 125 metres (410 ft) on each side.
                 During its construction, the Eiffel Tower surpassed the
                 Washington Monument to become the tallest man-made structure in the world,
                 a title it held for 41 years until the Chrysler Building
                 in New York City was finished in 1930.
                 It was the first structure to reach a height of 300 metres.
                 Due to the addition of a broadcasting aerial at the top of the tower in 1957,
                 it is now taller than the Chrysler Building by 5.2 metres (17 ft).
                 Excluding transmitters, the Eiffel Tower is the second tallest
                 free-standing structure in France after the Millau Viaduct.
                 """
    }
]
print(synopsis_chain.apply(test_prompts))
comet_callback.flush_tracker(synopsis_chain, finish=True)
previous
Cohere
next
Databerry
 Contents

Install Comet and Dependencies
Initialize Comet and Set your Credentials
Set OpenAI and SerpAPI credentials
Scenario 1: Using just an LLM
Scenario 2: Using an LLM in a Chain
Scenario 3: Using An Agent with Tools
Scenario 4: Using Custom Evaluation Metrics
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Databerry
 Contents
What is Databerry?
Quick start
Databerry#
This page covers how to use the Databerry within LangChain.
What is Databerry?#
Databerry is an open source document retrievial platform that helps to connect your personal data with Large Language Models.
Quick start#
Retrieving documents stored in Databerry from LangChain is very easy!
from langchain.retrievers import DataberryRetriever
retriever = DataberryRetriever(
    datastore_url="https://api.databerry.ai/query/clg1xg2h80000l708dymr0fxc",
    # api_key="DATABERRY_API_KEY", # optional if datastore is public
    # top_k=10 # optional
)
docs = retriever.get_relevant_documents("What's Databerry?")
previous
Comet
next
DeepInfra
 Contents

What is Databerry?
Quick start
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
DeepInfra
 Contents
Installation and Setup
Wrappers
LLM
DeepInfra#
This page covers how to use the DeepInfra ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific DeepInfra wrappers.
Installation and Setup#
Get your DeepInfra api key from this link here.
Get an DeepInfra api key and set it as an environment variable (DEEPINFRA_API_TOKEN)
Wrappers#
LLM#
There exists an DeepInfra LLM wrapper, which you can access with
from langchain.llms import DeepInfra
previous
Databerry
next
Deep Lake
 Contents

Installation and Setup
Wrappers
LLM
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Deep Lake
 Contents
Why Deep Lake?
More Resources
Installation and Setup
Wrappers
VectorStore
Deep Lake#
This page covers how to use the Deep Lake ecosystem within LangChain.
Why Deep Lake?#
More than just a (multi-modal) vector store. You can later use the dataset to fine-tune your own LLM models.
Not only stores embeddings, but also the original data with automatic version control.
Truly serverless. Doesn’t require another service and can be used with major cloud providers (AWS S3, GCS, etc.)
More Resources#
Ultimate Guide to LangChain & Deep Lake: Build ChatGPT to Answer Questions on Your Financial Data
Twitter the-algorithm codebase analysis with Deep Lake
Here is whitepaper and academic paper for Deep Lake
Here is a set of additional resources available for review: Deep Lake, Getting Started and Tutorials
Installation and Setup#
Install the Python package with pip install deeplake
Wrappers#
VectorStore#
There exists a wrapper around Deep Lake, a data lake for Deep Learning applications, allowing you to use it as a vector store (for now), whether for semantic search or example selection.
To import this vectorstore:
from langchain.vectorstores import DeepLake
For a more detailed walkthrough of the Deep Lake wrapper, see this notebook
previous
DeepInfra
next
ForefrontAI
 Contents

Why Deep Lake?
More Resources
Installation and Setup
Wrappers
VectorStore
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
ForefrontAI
 Contents
Installation and Setup
Wrappers
LLM
ForefrontAI#
This page covers how to use the ForefrontAI ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific ForefrontAI wrappers.
Installation and Setup#
Get an ForefrontAI api key and set it as an environment variable (FOREFRONTAI_API_KEY)
Wrappers#
LLM#
There exists an ForefrontAI LLM wrapper, which you can access with
from langchain.llms import ForefrontAI
previous
Deep Lake
next
Google Search Wrapper
 Contents

Installation and Setup
Wrappers
LLM
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Google Search Wrapper
 Contents
Installation and Setup
Wrappers
Utility
Tool
Google Search Wrapper#
This page covers how to use the Google Search API within LangChain.
It is broken into two parts: installation and setup, and then references to the specific Google Search wrapper.
Installation and Setup#
Install requirements with pip install google-api-python-client
Set up a Custom Search Engine, following these instructions
Get an API Key and Custom Search Engine ID from the previous step, and set them as environment variables GOOGLE_API_KEY and GOOGLE_CSE_ID respectively
Wrappers#
Utility#
There exists a GoogleSearchAPIWrapper utility which wraps this API. To import this utility:
from langchain.utilities import GoogleSearchAPIWrapper
For a more detailed walkthrough of this wrapper, see this notebook.
Tool#
You can also easily load this wrapper as a Tool (to use with an Agent).
You can do this with:
from langchain.agents import load_tools
tools = load_tools(["google-search"])
For more information on this, see this page
previous
ForefrontAI
next
Google Serper Wrapper
 Contents

Installation and Setup
Wrappers
Utility
Tool
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Google Serper Wrapper
 Contents
Setup
Wrappers
Utility
Output
Tool
Google Serper Wrapper#
This page covers how to use the Serper Google Search API within LangChain. Serper is a low-cost Google Search API that can be used to add answer box, knowledge graph, and organic results data from Google Search.
It is broken into two parts: setup, and then references to the specific Google Serper wrapper.
Setup#
Go to serper.dev to sign up for a free account
Get the api key and set it as an environment variable (SERPER_API_KEY)
Wrappers#
Utility#
There exists a GoogleSerperAPIWrapper utility which wraps this API. To import this utility:
from langchain.utilities import GoogleSerperAPIWrapper
You can use it as part of a Self Ask chain:
from langchain.utilities import GoogleSerperAPIWrapper
from langchain.llms.openai import OpenAI
from langchain.agents import initialize_agent, Tool
from langchain.agents import AgentType
import os
os.environ["SERPER_API_KEY"] = ""
os.environ['OPENAI_API_KEY'] = ""
llm = OpenAI(temperature=0)
search = GoogleSerperAPIWrapper()
tools = [
    Tool(
        name="Intermediate Answer",
        func=search.run,
        description="useful for when you need to ask with search"
    )
]
self_ask_with_search = initialize_agent(tools, llm, agent=AgentType.SELF_ASK_WITH_SEARCH, verbose=True)
self_ask_with_search.run("What is the hometown of the reigning men's U.S. Open champion?")
Output#
Entering new AgentExecutor chain...
 Yes.
Follow up: Who is the reigning men's U.S. Open champion?


Yes.
Follow up: Who is the reigning men's U.S. Open champion?
Intermediate answer: Current champions Carlos Alcaraz, 2022 men's singles champion.
Follow up: Where is Carlos Alcaraz from?
Intermediate answer: El Palmar, Spain
So the final answer is: El Palmar, Spain
> Finished chain.
'El Palmar, Spain'
For a more detailed walkthrough of this wrapper, see this notebook.
Tool#
You can also easily load this wrapper as a Tool (to use with an Agent).
You can do this with:
from langchain.agents import load_tools
tools = load_tools(["google-serper"])
For more information on this, see this page
previous
Google Search Wrapper
next
GooseAI
 Contents

Setup
Wrappers
Utility
Output
Tool
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
GooseAI
 Contents
Installation and Setup
Wrappers
LLM
GooseAI#
This page covers how to use the GooseAI ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific GooseAI wrappers.
Installation and Setup#
Install the Python SDK with pip install openai
Get your GooseAI api key from this link here.
Set the environment variable (GOOSEAI_API_KEY).
import os
os.environ["GOOSEAI_API_KEY"] = "YOUR_API_KEY"
Wrappers#
LLM#
There exists an GooseAI LLM wrapper, which you can access with:
from langchain.llms import GooseAI
previous
Google Serper Wrapper
next
GPT4All
 Contents

Installation and Setup
Wrappers
LLM
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
GPT4All
 Contents
Installation and Setup
Usage
GPT4All
Model File
GPT4All#
This page covers how to use the GPT4All wrapper within LangChain. The tutorial is divided into two parts: installation and setup, followed by usage with an example.
Installation and Setup#
Install the Python package with pip install pyllamacpp
Download a GPT4All model and place it in your desired directory
Usage#
GPT4All#
To use the GPT4All wrapper, you need to provide the path to the pre-trained model file and the model’s configuration.
from langchain.llms import GPT4All
# Instantiate the model. Callbacks support token-wise streaming
model = GPT4All(model="./models/gpt4all-model.bin", n_ctx=512, n_threads=8)
# Generate text
response = model("Once upon a time, ")
You can also customize the generation parameters, such as n_predict, temp, top_p, top_k, and others.
To stream the model’s predictions, add in a CallbackManager.
from langchain.llms import GPT4All
from langchain.callbacks.base import CallbackManager
from langchain.callbacks.streaming_stdout import StreamingStdOutCallbackHandler
# There are many CallbackHandlers supported, such as
# from langchain.callbacks.streamlit import StreamlitCallbackHandler
callback_manager = CallbackManager([StreamingStdOutCallbackHandler()])
model = GPT4All(model="./models/gpt4all-model.bin", n_ctx=512, n_threads=8, callback_handler=callback_handler, verbose=True)
# Generate text. Tokens are streamed through the callback manager.
model("Once upon a time, ")
Model File#
You can find links to model file downloads in the pyllamacpp repository.


You can find links to model file downloads in the pyllamacpp repository.
For a more detailed walkthrough of this, see this notebook
previous
GooseAI
next
Graphsignal
 Contents

Installation and Setup
Usage
GPT4All
Model File
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Graphsignal
 Contents
Installation and Setup
Tracing and Monitoring
Graphsignal#
This page covers how to use Graphsignal to trace and monitor LangChain. Graphsignal enables full visibility into your application. It provides latency breakdowns by chains and tools, exceptions with full context, data monitoring, compute/GPU utilization, OpenAI cost analytics, and more.
Installation and Setup#
Install the Python library with pip install graphsignal
Create free Graphsignal account here
Get an API key and set it as an environment variable (GRAPHSIGNAL_API_KEY)
Tracing and Monitoring#
Graphsignal automatically instruments and starts tracing and monitoring chains. Traces and metrics are then available in your Graphsignal dashboards.
Initialize the tracer by providing a deployment name:
import graphsignal
graphsignal.configure(deployment='my-langchain-app-prod')
To additionally trace any function or code, you can use a decorator or a context manager:
@graphsignal.trace_function
def handle_request():
    chain.run("some initial text")
with graphsignal.start_trace('my-chain'):
    chain.run("some initial text")
Optionally, enable profiling to record function-level statistics for each trace.
with graphsignal.start_trace(
        'my-chain', options=graphsignal.TraceOptions(enable_profiling=True)):
    chain.run("some initial text")
See the Quick Start guide for complete setup instructions.
previous
GPT4All
next
Hazy Research
 Contents

Installation and Setup
Tracing and Monitoring
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Hazy Research
 Contents
Installation and Setup
Wrappers
LLM
Hazy Research#
This page covers how to use the Hazy Research ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific Hazy Research wrappers.
Installation and Setup#
To use the manifest, install it with pip install manifest-ml
Wrappers#
LLM#
There exists an LLM wrapper around Hazy Research’s manifest library.
manifest is a python library which is itself a wrapper around many model providers, and adds in caching, history, and more.
To use this wrapper:
from langchain.llms.manifest import ManifestWrapper
previous
Graphsignal
next
Helicone
 Contents

Installation and Setup
Wrappers
LLM
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Helicone
 Contents
What is Helicone?
Quick start
How to enable Helicone caching
How to use Helicone custom properties
Helicone#
This page covers how to use the Helicone ecosystem within LangChain.
What is Helicone?#
Helicone is an open source observability platform that proxies your OpenAI traffic and provides you key insights into your spend, latency and usage.
Quick start#
With your LangChain environment you can just add the following parameter.
export OPENAI_API_BASE="https://oai.hconeai.com/v1"
Now head over to helicone.ai to create your account, and add your OpenAI API key within our dashboard to view your logs.
How to enable Helicone caching#
from langchain.llms import OpenAI
import openai
openai.api_base = "https://oai.hconeai.com/v1"
llm = OpenAI(temperature=0.9, headers={"Helicone-Cache-Enabled": "true"})
text = "What is a helicone?"
print(llm(text))
Helicone caching docs
How to use Helicone custom properties#
from langchain.llms import OpenAI
import openai
openai.api_base = "https://oai.hconeai.com/v1"
llm = OpenAI(temperature=0.9, headers={
        "Helicone-Property-Session": "24",
        "Helicone-Property-Conversation": "support_issue_2",
        "Helicone-Property-App": "mobile",
      })
text = "What is a helicone?"
print(llm(text))
Helicone property docs
previous
Hazy Research
next
Hugging Face
 Contents

What is Helicone?
Quick start
How to enable Helicone caching
How to use Helicone custom properties


Quick start
How to enable Helicone caching
How to use Helicone custom properties
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Hugging Face
 Contents
Installation and Setup
Wrappers
LLM
Embeddings
Tokenizer
Datasets
Hugging Face#
This page covers how to use the Hugging Face ecosystem (including the Hugging Face Hub) within LangChain.
It is broken into two parts: installation and setup, and then references to specific Hugging Face wrappers.
Installation and Setup#
If you want to work with the Hugging Face Hub:
Install the Hub client library with pip install huggingface_hub
Create a Hugging Face account (it’s free!)
Create an access token and set it as an environment variable (HUGGINGFACEHUB_API_TOKEN)
If you want work with the Hugging Face Python libraries:
Install pip install transformers for working with models and tokenizers
Install pip install datasets for working with datasets
Wrappers#
LLM#
There exists two Hugging Face LLM wrappers, one for a local pipeline and one for a model hosted on Hugging Face Hub.
Note that these wrappers only work for models that support the following tasks: text2text-generation, text-generation
To use the local pipeline wrapper:
from langchain.llms import HuggingFacePipeline
To use a the wrapper for a model hosted on Hugging Face Hub:
from langchain.llms import HuggingFaceHub
For a more detailed walkthrough of the Hugging Face Hub wrapper, see this notebook
Embeddings#
There exists two Hugging Face Embeddings wrappers, one for a local model and one for a model hosted on Hugging Face Hub.
Note that these wrappers only work for sentence-transformers models.
To use the local pipeline wrapper:
from langchain.embeddings import HuggingFaceEmbeddings
To use a the wrapper for a model hosted on Hugging Face Hub:
from langchain.embeddings import HuggingFaceHubEmbeddings


from langchain.embeddings import HuggingFaceHubEmbeddings
For a more detailed walkthrough of this, see this notebook
Tokenizer#
There are several places you can use tokenizers available through the transformers package.
By default, it is used to count tokens for all LLMs.
You can also use it to count tokens when splitting documents with
from langchain.text_splitter import CharacterTextSplitter
CharacterTextSplitter.from_huggingface_tokenizer(...)
For a more detailed walkthrough of this, see this notebook
Datasets#
The Hugging Face Hub has lots of great datasets that can be used to evaluate your LLM chains.
For a detailed walkthrough of how to use them to do so, see this notebook
previous
Helicone
next
Jina
 Contents

Installation and Setup
Wrappers
LLM
Embeddings
Tokenizer
Datasets
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Jina
 Contents
Installation and Setup
Wrappers
Embeddings
Jina#
This page covers how to use the Jina ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific Jina wrappers.
Installation and Setup#
Install the Python SDK with pip install jina
Get a Jina AI Cloud auth token from here and set it as an environment variable (JINA_AUTH_TOKEN)
Wrappers#
Embeddings#
There exists a Jina Embeddings wrapper, which you can access with
from langchain.embeddings import JinaEmbeddings
For a more detailed walkthrough of this, see this notebook
previous
Hugging Face
next
Llama.cpp
 Contents

Installation and Setup
Wrappers
Embeddings
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Llama.cpp
 Contents
Installation and Setup
Wrappers
LLM
Embeddings
Llama.cpp#
This page covers how to use llama.cpp within LangChain.
It is broken into two parts: installation and setup, and then references to specific Llama-cpp wrappers.
Installation and Setup#
Install the Python package with pip install llama-cpp-python
Download one of the supported models and convert them to the llama.cpp format per the instructions
Wrappers#
LLM#
There exists a LlamaCpp LLM wrapper, which you can access with
from langchain.llms import LlamaCpp
For a more detailed walkthrough of this, see this notebook
Embeddings#
There exists a LlamaCpp Embeddings wrapper, which you can access with
from langchain.embeddings import LlamaCppEmbeddings
For a more detailed walkthrough of this, see this notebook
previous
Jina
next
Milvus
 Contents

Installation and Setup
Wrappers
LLM
Embeddings
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Milvus
 Contents
Installation and Setup
Wrappers
VectorStore
Milvus#
This page covers how to use the Milvus ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific Milvus wrappers.
Installation and Setup#
Install the Python SDK with pip install pymilvus
Wrappers#
VectorStore#
There exists a wrapper around Milvus indexes, allowing you to use it as a vectorstore,
whether for semantic search or example selection.
To import this vectorstore:
from langchain.vectorstores import Milvus
For a more detailed walkthrough of the Miluvs wrapper, see this notebook
previous
Llama.cpp
next
Modal
 Contents

Installation and Setup
Wrappers
VectorStore
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Modal
 Contents
Installation and Setup
Define your Modal Functions and Webhooks
Wrappers
LLM
Modal#
This page covers how to use the Modal ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific Modal wrappers.
Installation and Setup#
Install with pip install modal-client
Run modal token new
Define your Modal Functions and Webhooks#
You must include a prompt. There is a rigid response structure.
class Item(BaseModel):
    prompt: str
@stub.webhook(method="POST")
def my_webhook(item: Item):
    return {"prompt": my_function.call(item.prompt)}
An example with GPT2:
from pydantic import BaseModel
import modal
stub = modal.Stub("example-get-started")
volume = modal.SharedVolume().persist("gpt2_model_vol")
CACHE_PATH = "/root/model_cache"
@stub.function(
    gpu="any",
    image=modal.Image.debian_slim().pip_install(
        "tokenizers", "transformers", "torch", "accelerate"
    ),
    shared_volumes={CACHE_PATH: volume},
    retries=3,
)
def run_gpt2(text: str):
    from transformers import GPT2Tokenizer, GPT2LMHeadModel
    tokenizer = GPT2Tokenizer.from_pretrained('gpt2')
    model = GPT2LMHeadModel.from_pretrained('gpt2')
    encoded_input = tokenizer(text, return_tensors='pt').input_ids
    output = model.generate(encoded_input, max_length=50, do_sample=True)
    return tokenizer.decode(output[0], skip_special_tokens=True)
class Item(BaseModel):
    prompt: str
@stub.webhook(method="POST")
def get_text(item: Item):


@stub.webhook(method="POST")
def get_text(item: Item):
    return {"prompt": run_gpt2.call(item.prompt)}
Wrappers#
LLM#
There exists an Modal LLM wrapper, which you can access with
from langchain.llms import Modal
previous
Milvus
next
MyScale
 Contents

Installation and Setup
Define your Modal Functions and Webhooks
Wrappers
LLM
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
MyScale
 Contents
Introduction
Installation and Setup
Setting up envrionments
Wrappers
VectorStore
MyScale#
This page covers how to use MyScale vector database within LangChain.
It is broken into two parts: installation and setup, and then references to specific MyScale wrappers.
With MyScale, you can manage both structured and unstructured (vectorized) data, and perform joint queries and analytics on both types of data using SQL. Plus, MyScale’s cloud-native OLAP architecture, built on top of ClickHouse, enables lightning-fast data processing even on massive datasets.
Introduction#
Overview to MyScale and High performance vector search
You can now register on our SaaS and start a cluster now!
If you are also interested in how we managed to integrate SQL and vector, please refer to this document for further syntax reference.
We also deliver with live demo on huggingface! Please checkout our huggingface space! They search millions of vector within a blink!
Installation and Setup#
Install the Python SDK with pip install clickhouse-connect
Setting up envrionments#
There are two ways to set up parameters for myscale index.
Environment Variables
Before you run the app, please set the environment variable with export:
export MYSCALE_URL='<your-endpoints-url>' MYSCALE_PORT=<your-endpoints-port> MYSCALE_USERNAME=<your-username> MYSCALE_PASSWORD=<your-password> ...
You can easily find your account, password and other info on our SaaS. For details please refer to this document
Every attributes under MyScaleSettings can be set with prefix MYSCALE_ and is case insensitive.
Create MyScaleSettings object with parameters
from langchain.vectorstores import MyScale, MyScaleSettings
config = MyScaleSetting(host="<your-backend-url>", port=8443, ...)
index = MyScale(embedding_function, config)


index = MyScale(embedding_function, config)
index.add_documents(...)
Wrappers#
supported functions:
add_texts
add_documents
from_texts
from_documents
similarity_search
asimilarity_search
similarity_search_by_vector
asimilarity_search_by_vector
similarity_search_with_relevance_scores
VectorStore#
There exists a wrapper around MyScale database, allowing you to use it as a vectorstore,
whether for semantic search or similar example retrieval.
To import this vectorstore:
from langchain.vectorstores import MyScale
For a more detailed walkthrough of the MyScale wrapper, see this notebook
previous
Modal
next
NLPCloud
 Contents

Introduction
Installation and Setup
Setting up envrionments
Wrappers
VectorStore
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
NLPCloud
 Contents
Installation and Setup
Wrappers
LLM
NLPCloud#
This page covers how to use the NLPCloud ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific NLPCloud wrappers.
Installation and Setup#
Install the Python SDK with pip install nlpcloud
Get an NLPCloud api key and set it as an environment variable (NLPCLOUD_API_KEY)
Wrappers#
LLM#
There exists an NLPCloud LLM wrapper, which you can access with
from langchain.llms import NLPCloud
previous
MyScale
next
OpenAI
 Contents

Installation and Setup
Wrappers
LLM
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
OpenAI
 Contents
Installation and Setup
Wrappers
LLM
Embeddings
Tokenizer
Moderation
OpenAI#
This page covers how to use the OpenAI ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific OpenAI wrappers.
Installation and Setup#
Install the Python SDK with pip install openai
Get an OpenAI api key and set it as an environment variable (OPENAI_API_KEY)
If you want to use OpenAI’s tokenizer (only available for Python 3.9+), install it with pip install tiktoken
Wrappers#
LLM#
There exists an OpenAI LLM wrapper, which you can access with
from langchain.llms import OpenAI
If you are using a model hosted on Azure, you should use different wrapper for that:
from langchain.llms import AzureOpenAI
For a more detailed walkthrough of the Azure wrapper, see this notebook
Embeddings#
There exists an OpenAI Embeddings wrapper, which you can access with
from langchain.embeddings import OpenAIEmbeddings
For a more detailed walkthrough of this, see this notebook
Tokenizer#
There are several places you can use the tiktoken tokenizer. By default, it is used to count tokens
for OpenAI LLMs.
You can also use it to count tokens when splitting documents with
from langchain.text_splitter import CharacterTextSplitter
CharacterTextSplitter.from_tiktoken_encoder(...)
For a more detailed walkthrough of this, see this notebook
Moderation#
You can also access the OpenAI content moderation endpoint with
from langchain.chains import OpenAIModerationChain
For a more detailed walkthrough of this, see this notebook
previous
NLPCloud
next
OpenSearch
 Contents

Installation and Setup
Wrappers
LLM
Embeddings
Tokenizer


Contents

Installation and Setup
Wrappers
LLM
Embeddings
Tokenizer
Moderation
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
OpenSearch
 Contents
Installation and Setup
Wrappers
VectorStore
OpenSearch#
This page covers how to use the OpenSearch ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific OpenSearch wrappers.
Installation and Setup#
Install the Python package with pip install opensearch-py
Wrappers#
VectorStore#
There exists a wrapper around OpenSearch vector databases, allowing you to use it as a vectorstore
for semantic search using approximate vector search powered by lucene, nmslib and faiss engines
or using painless scripting and script scoring functions for bruteforce vector search.
To import this vectorstore:
from langchain.vectorstores import OpenSearchVectorSearch
For a more detailed walkthrough of the OpenSearch wrapper, see this notebook
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OpenAI
next
Petals
 Contents

Installation and Setup
Wrappers
VectorStore
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Petals
 Contents
Installation and Setup
Wrappers
LLM
Petals#
This page covers how to use the Petals ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific Petals wrappers.
Installation and Setup#
Install with pip install petals
Get a Hugging Face api key and set it as an environment variable (HUGGINGFACE_API_KEY)
Wrappers#
LLM#
There exists an Petals LLM wrapper, which you can access with
from langchain.llms import Petals
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OpenSearch
next
PGVector
 Contents

Installation and Setup
Wrappers
LLM
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
PGVector
 Contents
Installation
Setup
Wrappers
VectorStore
Usage
PGVector#
This page covers how to use the Postgres PGVector ecosystem within LangChain
It is broken into two parts: installation and setup, and then references to specific PGVector wrappers.
Installation#
Install the Python package with pip install pgvector
Setup#
The first step is to create a database with the pgvector extension installed.
Follow the steps at PGVector Installation Steps to install the database and the extension. The docker image is the easiest way to get started.
Wrappers#
VectorStore#
There exists a wrapper around Postgres vector databases, allowing you to use it as a vectorstore,
whether for semantic search or example selection.
To import this vectorstore:
from langchain.vectorstores.pgvector import PGVector
Usage#
For a more detailed walkthrough of the PGVector Wrapper, see this notebook
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Petals
next
Pinecone
 Contents

Installation
Setup
Wrappers
VectorStore
Usage
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Pinecone
 Contents
Installation and Setup
Wrappers
VectorStore
Pinecone#
This page covers how to use the Pinecone ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific Pinecone wrappers.
Installation and Setup#
Install the Python SDK with pip install pinecone-client
Wrappers#
VectorStore#
There exists a wrapper around Pinecone indexes, allowing you to use it as a vectorstore,
whether for semantic search or example selection.
To import this vectorstore:
from langchain.vectorstores import Pinecone
For a more detailed walkthrough of the Pinecone wrapper, see this notebook
previous
PGVector
next
Prediction Guard
 Contents

Installation and Setup
Wrappers
VectorStore
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Prediction Guard
 Contents
Installation and Setup
LLM Wrapper
Example usage
Prediction Guard#
This page covers how to use the Prediction Guard ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific Prediction Guard wrappers.
Installation and Setup#
Install the Python SDK with pip install predictionguard
Get an Prediction Guard access token (as described here) and set it as an environment variable (PREDICTIONGUARD_TOKEN)
LLM Wrapper#
There exists a Prediction Guard LLM wrapper, which you can access with
from langchain.llms import PredictionGuard
You can provide the name of your Prediction Guard “proxy” as an argument when initializing the LLM:
pgllm = PredictionGuard(name="your-text-gen-proxy")
Alternatively, you can use Prediction Guard’s default proxy for SOTA LLMs:
pgllm = PredictionGuard(name="default-text-gen")
You can also provide your access token directly as an argument:
pgllm = PredictionGuard(name="default-text-gen", token="<your access token>")
Example usage#
Basic usage of the LLM wrapper:
from langchain.llms import PredictionGuard
pgllm = PredictionGuard(name="default-text-gen")
pgllm("Tell me a joke")
Basic LLM Chaining with the Prediction Guard wrapper:
from langchain import PromptTemplate, LLMChain
from langchain.llms import PredictionGuard
template = """Question: {question}
Answer: Let's think step by step."""
prompt = PromptTemplate(template=template, input_variables=["question"])
llm_chain = LLMChain(prompt=prompt, llm=PredictionGuard(name="default-text-gen"), verbose=True)
question = "What NFL team won the Super Bowl in the year Justin Beiber was born?"
llm_chain.predict(question=question)
previous


llm_chain.predict(question=question)
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Pinecone
next
PromptLayer
 Contents

Installation and Setup
LLM Wrapper
Example usage
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
PromptLayer
 Contents
Installation and Setup
Wrappers
LLM
PromptLayer#
This page covers how to use PromptLayer within LangChain.
It is broken into two parts: installation and setup, and then references to specific PromptLayer wrappers.
Installation and Setup#
If you want to work with PromptLayer:
Install the promptlayer python library pip install promptlayer
Create a PromptLayer account
Create an api token and set it as an environment variable (PROMPTLAYER_API_KEY)
Wrappers#
LLM#
There exists an PromptLayer OpenAI LLM wrapper, which you can access with
from langchain.llms import PromptLayerOpenAI
To tag your requests, use the argument pl_tags when instanializing the LLM
from langchain.llms import PromptLayerOpenAI
llm = PromptLayerOpenAI(pl_tags=["langchain-requests", "chatbot"])
To get the PromptLayer request id, use the argument return_pl_id when instanializing the LLM
from langchain.llms import PromptLayerOpenAI
llm = PromptLayerOpenAI(return_pl_id=True)
This will add the PromptLayer request ID in the generation_info field of the Generation returned when using .generate or .agenerate
For example:
llm_results = llm.generate(["hello world"])
for res in llm_results.generations:
    print("pl request id: ", res[0].generation_info["pl_request_id"])
You can use the PromptLayer request ID to add a prompt, score, or other metadata to your request. Read more about it here.
This LLM is identical to the OpenAI LLM, except that
all your requests will be logged to your PromptLayer account
you can add pl_tags when instantializing to tag your requests on PromptLayer


you can add pl_tags when instantializing to tag your requests on PromptLayer
you can add return_pl_id when instantializing to return a PromptLayer request id to use while tracking requests.
PromptLayer also provides native wrappers for PromptLayerChatOpenAI and PromptLayerOpenAIChat
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Prediction Guard
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Qdrant
 Contents

Installation and Setup
Wrappers
LLM
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Qdrant
 Contents
Installation and Setup
Wrappers
VectorStore
Qdrant#
This page covers how to use the Qdrant ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific Qdrant wrappers.
Installation and Setup#
Install the Python SDK with pip install qdrant-client
Wrappers#
VectorStore#
There exists a wrapper around Qdrant indexes, allowing you to use it as a vectorstore,
whether for semantic search or example selection.
To import this vectorstore:
from langchain.vectorstores import Qdrant
For a more detailed walkthrough of the Qdrant wrapper, see this notebook
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PromptLayer
next
Replicate
 Contents

Installation and Setup
Wrappers
VectorStore
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Replicate
 Contents
Installation and Setup
Calling a model
Replicate#
This page covers how to run models on Replicate within LangChain.
Installation and Setup#
Create a Replicate account. Get your API key and set it as an environment variable (REPLICATE_API_TOKEN)
Install the Replicate python client with pip install replicate
Calling a model#
Find a model on the Replicate explore page, and then paste in the model name and version in this format: owner-name/model-name:version
For example, for this flan-t5 model, click on the API tab. The model name/version would be: daanelson/flan-t5:04e422a9b85baed86a4f24981d7f9953e20c5fd82f6103b74ebc431588e1cec8
Only the model param is required, but any other model parameters can also be passed in with the format input={model_param: value, ...}
For example, if we were running stable diffusion and wanted to change the image dimensions:
Replicate(model="stability-ai/stable-diffusion:db21e45d3f7023abc2a46ee38a23973f6dce16bb082a930b0c49861f96d1e5bf", input={'image_dimensions': '512x512'})
Note that only the first output of a model will be returned.
From here, we can initialize our model:
llm = Replicate(model="daanelson/flan-t5:04e422a9b85baed86a4f24981d7f9953e20c5fd82f6103b74ebc431588e1cec8")
And run it:
prompt = """
Answer the following yes/no question by reasoning step by step.


prompt = """
Answer the following yes/no question by reasoning step by step.
Can a dog drive a car?
"""
llm(prompt)
We can call any Replicate model (not just LLMs) using this syntax. For example, we can call Stable Diffusion:
text2image = Replicate(model="stability-ai/stable-diffusion:db21e45d3f7023abc2a46ee38a23973f6dce16bb082a930b0c49861f96d1e5bf",
                       input={'image_dimensions'='512x512'}
image_output = text2image("A cat riding a motorcycle by Picasso")
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Qdrant
next
Runhouse
 Contents

Installation and Setup
Calling a model
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Runhouse
 Contents
Installation and Setup
Self-hosted LLMs
Self-hosted Embeddings
Runhouse#
This page covers how to use the Runhouse ecosystem within LangChain.
It is broken into three parts: installation and setup, LLMs, and Embeddings.
Installation and Setup#
Install the Python SDK with pip install runhouse
If you’d like to use on-demand cluster, check your cloud credentials with sky check
Self-hosted LLMs#
For a basic self-hosted LLM, you can use the SelfHostedHuggingFaceLLM class. For more
custom LLMs, you can use the SelfHostedPipeline parent class.
from langchain.llms import SelfHostedPipeline, SelfHostedHuggingFaceLLM
For a more detailed walkthrough of the Self-hosted LLMs, see this notebook
Self-hosted Embeddings#
There are several ways to use self-hosted embeddings with LangChain via Runhouse.
For a basic self-hosted embedding from a Hugging Face Transformers model, you can use
the SelfHostedEmbedding class.
from langchain.llms import SelfHostedPipeline, SelfHostedHuggingFaceLLM
For a more detailed walkthrough of the Self-hosted Embeddings, see this notebook
previous
Replicate
next
RWKV-4
 Contents

Installation and Setup
Self-hosted LLMs
Self-hosted Embeddings
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
RWKV-4
 Contents
Installation and Setup
Usage
RWKV
Model File
Rwkv-4 models -> recommended VRAM
RWKV-4#
This page covers how to use the RWKV-4 wrapper within LangChain.
It is broken into two parts: installation and setup, and then usage with an example.
Installation and Setup#
Install the Python package with pip install rwkv
Install the tokenizer Python package with pip install tokenizer
Download a RWKV model and place it in your desired directory
Download the tokens file
Usage#
RWKV#
To use the RWKV wrapper, you need to provide the path to the pre-trained model file and the tokenizer’s configuration.
from langchain.llms import RWKV
# Test the model
```python
def generate_prompt(instruction, input=None):
    if input:
        return f"""Below is an instruction that describes a task, paired with an input that provides further context. Write a response that appropriately completes the request.
# Instruction:
{instruction}
# Input:
{input}
# Response:
"""
    else:
        return f"""Below is an instruction that describes a task. Write a response that appropriately completes the request.
# Instruction:
{instruction}
# Response:
"""
model = RWKV(model="./models/RWKV-4-Raven-3B-v7-Eng-20230404-ctx4096.pth", strategy="cpu fp32", tokens_path="./rwkv/20B_tokenizer.json")
response = model(generate_prompt("Once upon a time, "))
Model File#
You can find links to model file downloads at the RWKV-4-Raven repository.
Rwkv-4 models -> recommended VRAM#
RWKV VRAM
Model | 8bit | bf16/fp16 | fp32


RWKV VRAM
Model | 8bit | bf16/fp16 | fp32
14B   | 16GB | 28GB      | >50GB
7B    | 8GB  | 14GB      | 28GB
3B    | 2.8GB| 6GB       | 12GB
1b5   | 1.3GB| 3GB       | 6GB
See the rwkv pip page for more information about strategies, including streaming and cuda support.
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Runhouse
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SearxNG Search API
 Contents

Installation and Setup
Usage
RWKV
Model File
Rwkv-4 models -> recommended VRAM
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
SearxNG Search API
 Contents
Installation and Setup
Self Hosted Instance:
Wrappers
Utility
Tool
SearxNG Search API#
This page covers how to use the SearxNG search API within LangChain.
It is broken into two parts: installation and setup, and then references to the specific SearxNG API wrapper.
Installation and Setup#
While it is possible to utilize the wrapper in conjunction with  public searx
instances these instances frequently do not permit API
access (see note on output format below) and have limitations on the frequency
of requests. It is recommended to opt for a self-hosted instance instead.
Self Hosted Instance:#
See this page for installation instructions.
When you install SearxNG, the only active output format by default is the HTML format.
You need to activate the json format to use the API. This can be done by adding the following line to the settings.yml file:
search:
    formats:
        - html
        - json
You can make sure that the API is working by issuing a curl request to the API endpoint:
curl -kLX GET --data-urlencode q='langchain' -d format=json http://localhost:8888
This should return a JSON object with the results.
Wrappers#
Utility#
To use the wrapper we need to pass the host of the SearxNG instance to the wrapper with:
1. the named parameter searx_host when creating the instance.
2. exporting the environment variable SEARXNG_HOST.
You can use the wrapper to get results from a SearxNG instance.
from langchain.utilities import SearxSearchWrapper
s = SearxSearchWrapper(searx_host="http://localhost:8888")
s.run("what is a large language model?")


s.run("what is a large language model?")
Tool#
You can also load this wrapper as a Tool (to use with an Agent).
You can do this with:
from langchain.agents import load_tools
tools = load_tools(["searx-search"],
                    searx_host="http://localhost:8888",
                    engines=["github"])
Note that we could optionally pass custom engines to use.
If you want to obtain results with metadata as json you can use:
tools = load_tools(["searx-search-results-json"],
                    searx_host="http://localhost:8888",
                    num_results=5)
For more information on tools, see this page
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RWKV-4
next
SerpAPI
 Contents

Installation and Setup
Self Hosted Instance:
Wrappers
Utility
Tool
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
SerpAPI
 Contents
Installation and Setup
Wrappers
Utility
Tool
SerpAPI#
This page covers how to use the SerpAPI search APIs within LangChain.
It is broken into two parts: installation and setup, and then references to the specific SerpAPI wrapper.
Installation and Setup#
Install requirements with pip install google-search-results
Get a SerpAPI api key and either set it as an environment variable (SERPAPI_API_KEY)
Wrappers#
Utility#
There exists a SerpAPI utility which wraps this API. To import this utility:
from langchain.utilities import SerpAPIWrapper
For a more detailed walkthrough of this wrapper, see this notebook.
Tool#
You can also easily load this wrapper as a Tool (to use with an Agent).
You can do this with:
from langchain.agents import load_tools
tools = load_tools(["serpapi"])
For more information on this, see this page
previous
SearxNG Search API
next
StochasticAI
 Contents

Installation and Setup
Wrappers
Utility
Tool
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
StochasticAI
 Contents
Installation and Setup
Wrappers
LLM
StochasticAI#
This page covers how to use the StochasticAI ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific StochasticAI wrappers.
Installation and Setup#
Install with pip install stochasticx
Get an StochasticAI api key and set it as an environment variable (STOCHASTICAI_API_KEY)
Wrappers#
LLM#
There exists an StochasticAI LLM wrapper, which you can access with
from langchain.llms import StochasticAI
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SerpAPI
next
Unstructured
 Contents

Installation and Setup
Wrappers
LLM
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Unstructured
 Contents
Installation and Setup
Wrappers
Data Loaders
Unstructured#
This page covers how to use the unstructured
ecosystem within LangChain. The unstructured package from
Unstructured.IO extracts clean text from raw source documents like
PDFs and Word documents.
This page is broken into two parts: installation and setup, and then references to specific
unstructured wrappers.
Installation and Setup#
Install the Python SDK with pip install "unstructured[local-inference]"
Install the following system dependencies if they are not already available on your system.
Depending on what document types you’re parsing, you may not need all of these.
libmagic-dev (filetype detection)
poppler-utils (images and PDFs)
tesseract-ocr(images and PDFs)
libreoffice (MS Office docs)
pandoc (EPUBs)
If you are parsing PDFs using the "hi_res" strategy, run the following to install the detectron2 model, which
unstructured uses for layout detection:
pip install "detectron2@git+https://github.com/facebookresearch/detectron2.git@e2ce8dc#egg=detectron2"
If detectron2 is not installed, unstructured will fallback to processing PDFs
using the "fast" strategy, which uses pdfminer directly and doesn’t require
detectron2.
Wrappers#
Data Loaders#
The primary unstructured wrappers within langchain are data loaders. The following
shows how to use the most basic unstructured data loader. There are other file-specific
data loaders available in the langchain.document_loaders module.
from langchain.document_loaders import UnstructuredFileLoader
loader = UnstructuredFileLoader("state_of_the_union.txt")
loader.load()


loader = UnstructuredFileLoader("state_of_the_union.txt")
loader.load()
If you instantiate the loader with UnstructuredFileLoader(mode="elements"), the loader
will track additional metadata like the page number and text type (i.e. title, narrative text)
when that information is available.
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StochasticAI
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Weights & Biases
 Contents

Installation and Setup
Wrappers
Data Loaders
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.ipynb
.pdf
Weights & Biases
Weights & Biases#
This notebook goes over how to track your LangChain experiments into one centralized Weights and Biases dashboard. To learn more about prompt engineering and the callback please refer to this Report which explains both alongside the resultant dashboards you can expect to see.
Run in Colab: https://colab.research.google.com/drive/1DXH4beT4HFaRKy_Vm4PoxhXVDRf7Ym8L?usp=sharing
View Report: https://wandb.ai/a-sh0ts/langchain_callback_demo/reports/Prompt-Engineering-LLMs-with-LangChain-and-W-B–VmlldzozNjk1NTUw#👋-how-to-build-a-callback-in-langchain-for-better-prompt-engineering
!pip install wandb
!pip install pandas
!pip install textstat
!pip install spacy
!python -m spacy download en_core_web_sm
import os
os.environ["WANDB_API_KEY"] = ""
# os.environ["OPENAI_API_KEY"] = ""
# os.environ["SERPAPI_API_KEY"] = ""
from datetime import datetime
from langchain.callbacks import WandbCallbackHandler, StdOutCallbackHandler
from langchain.callbacks.base import CallbackManager
from langchain.llms import OpenAI
Callback Handler that logs to Weights and Biases.
Parameters:
    job_type (str): The type of job.
    project (str): The project to log to.
    entity (str): The entity to log to.
    tags (list): The tags to log.
    group (str): The group to log to.
    name (str): The name of the run.
    notes (str): The notes to log.


notes (str): The notes to log.
    visualize (bool): Whether to visualize the run.
    complexity_metrics (bool): Whether to log complexity metrics.
    stream_logs (bool): Whether to stream callback actions to W&B
Default values for WandbCallbackHandler(...)
visualize: bool = False,
complexity_metrics: bool = False,
stream_logs: bool = False,
NOTE: For beta workflows we have made the default analysis based on textstat and the visualizations based on spacy
"""Main function.
This function is used to try the callback handler.
Scenarios:
1. OpenAI LLM
2. Chain with multiple SubChains on multiple generations
3. Agent with Tools
"""
session_group = datetime.now().strftime("%m.%d.%Y_%H.%M.%S")
wandb_callback = WandbCallbackHandler(
    job_type="inference",
    project="langchain_callback_demo",
    group=f"minimal_{session_group}",
    name="llm",
    tags=["test"],
)
manager = CallbackManager([StdOutCallbackHandler(), wandb_callback])
llm = OpenAI(temperature=0, callback_manager=manager, verbose=True)
wandb: Currently logged in as: harrison-chase. Use `wandb login --relogin` to force relogin


Tracking run with wandb version 0.14.0Run data is saved locally in /Users/harrisonchase/workplace/langchain/docs/ecosystem/wandb/run-20230318_150408-e47j1914Syncing run llm to Weights & Biases (docs) View project at https://wandb.ai/harrison-chase/langchain_callback_demo View run at https://wandb.ai/harrison-chase/langchain_callback_demo/runs/e47j1914wandb: WARNING The wandb callback is currently in beta and is subject to change based on updates to `langchain`. Please report any issues to https://github.com/wandb/wandb/issues with the tag `langchain`.
# Defaults for WandbCallbackHandler.flush_tracker(...)
reset: bool = True,
finish: bool = False,
The flush_tracker function is used to log LangChain sessions to Weights & Biases. It takes in the LangChain module or agent, and logs at minimum the prompts and generations alongside the serialized form of the LangChain module to the specified Weights & Biases project. By default we reset the session as opposed to concluding the session outright.
# SCENARIO 1 - LLM
llm_result = llm.generate(["Tell me a joke", "Tell me a poem"] * 3)
wandb_callback.flush_tracker(llm, name="simple_sequential")


wandb_callback.flush_tracker(llm, name="simple_sequential")
Waiting for W&B process to finish... (success). View run llm at: https://wandb.ai/harrison-chase/langchain_callback_demo/runs/e47j1914Synced 5 W&B file(s), 2 media file(s), 5 artifact file(s) and 0 other file(s)Find logs at: ./wandb/run-20230318_150408-e47j1914/logsTracking run with wandb version 0.14.0Run data is saved locally in /Users/harrisonchase/workplace/langchain/docs/ecosystem/wandb/run-20230318_150534-jyxma7huSyncing run simple_sequential to Weights & Biases (docs) View project at https://wandb.ai/harrison-chase/langchain_callback_demo View run at https://wandb.ai/harrison-chase/langchain_callback_demo/runs/jyxma7hu
from langchain.prompts import PromptTemplate
from langchain.chains import LLMChain
# SCENARIO 2 - Chain
template = """You are a playwright. Given the title of play, it is your job to write a synopsis for that title.
Title: {title}
Playwright: This is a synopsis for the above play:"""
prompt_template = PromptTemplate(input_variables=["title"], template=template)
synopsis_chain = LLMChain(llm=llm, prompt=prompt_template, callback_manager=manager)
test_prompts = [
    {
        "title": "documentary about good video games that push the boundary of game design"
    },
    {"title": "cocaine bear vs heroin wolf"},
    {"title": "the best in class mlops tooling"},
]
synopsis_chain.apply(test_prompts)


]
synopsis_chain.apply(test_prompts)
wandb_callback.flush_tracker(synopsis_chain, name="agent")
Waiting for W&B process to finish... (success). View run simple_sequential at: https://wandb.ai/harrison-chase/langchain_callback_demo/runs/jyxma7huSynced 4 W&B file(s), 2 media file(s), 6 artifact file(s) and 0 other file(s)Find logs at: ./wandb/run-20230318_150534-jyxma7hu/logsTracking run with wandb version 0.14.0Run data is saved locally in /Users/harrisonchase/workplace/langchain/docs/ecosystem/wandb/run-20230318_150550-wzy59zjqSyncing run agent to Weights & Biases (docs) View project at https://wandb.ai/harrison-chase/langchain_callback_demo View run at https://wandb.ai/harrison-chase/langchain_callback_demo/runs/wzy59zjq
from langchain.agents import initialize_agent, load_tools
from langchain.agents import AgentType
# SCENARIO 3 - Agent with Tools
tools = load_tools(["serpapi", "llm-math"], llm=llm, callback_manager=manager)
agent = initialize_agent(
    tools,
    llm,
    agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION,
    callback_manager=manager,
    verbose=True,
)
agent.run(
    "Who is Leo DiCaprio's girlfriend? What is her current age raised to the 0.43 power?"
)
wandb_callback.flush_tracker(agent, reset=False, finish=True)
> Entering new AgentExecutor chain...
 I need to find out who Leo DiCaprio's girlfriend is and then calculate her age raised to the 0.43 power.


Action: Search
Action Input: "Leo DiCaprio girlfriend"
Observation: DiCaprio had a steady girlfriend in Camila Morrone. He had been with the model turned actress for nearly five years, as they were first said to be dating at the end of 2017. And the now 26-year-old Morrone is no stranger to Hollywood.
Thought: I need to calculate her age raised to the 0.43 power.
Action: Calculator
Action Input: 26^0.43
Observation: Answer: 4.059182145592686
Thought: I now know the final answer.
Final Answer: Leo DiCaprio's girlfriend is Camila Morrone and her current age raised to the 0.43 power is 4.059182145592686.
> Finished chain.
Waiting for W&B process to finish... (success). View run agent at: https://wandb.ai/harrison-chase/langchain_callback_demo/runs/wzy59zjqSynced 5 W&B file(s), 2 media file(s), 7 artifact file(s) and 0 other file(s)Find logs at: ./wandb/run-20230318_150550-wzy59zjq/logs
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Unstructured
next
Weaviate
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Weaviate
 Contents
Installation and Setup
Wrappers
VectorStore
Weaviate#
This page covers how to use the Weaviate ecosystem within LangChain.
What is Weaviate?
Weaviate in a nutshell:
Weaviate is an open-source database of the type vector search engine.
Weaviate allows you to store JSON documents in a class property-like fashion while attaching machine learning vectors to these documents to represent them in vector space.
Weaviate can be used stand-alone (aka bring your vectors) or with a variety of modules that can do the vectorization for you and extend the core capabilities.
Weaviate has a GraphQL-API to access your data easily.
We aim to bring your vector search set up to production to query in mere milliseconds (check our open source benchmarks to see if Weaviate fits your use case).
Get to know Weaviate in the basics getting started guide in under five minutes.
Weaviate in detail:
Weaviate is a low-latency vector search engine with out-of-the-box support for different media types (text, images, etc.). It offers Semantic Search, Question-Answer Extraction, Classification, Customizable Models (PyTorch/TensorFlow/Keras), etc. Built from scratch in Go, Weaviate stores both objects and vectors, allowing for combining vector search with structured filtering and the fault tolerance of a cloud-native database. It is all accessible through GraphQL, REST, and various client-side programming languages.
Installation and Setup#
Install the Python SDK with pip install weaviate-client
Wrappers#
VectorStore#
There exists a wrapper around Weaviate indexes, allowing you to use it as a vectorstore,
whether for semantic search or example selection.
To import this vectorstore:
from langchain.vectorstores import Weaviate


To import this vectorstore:
from langchain.vectorstores import Weaviate
For a more detailed walkthrough of the Weaviate wrapper, see this notebook
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Weights & Biases
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Wolfram Alpha Wrapper
 Contents

Installation and Setup
Wrappers
VectorStore
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Wolfram Alpha Wrapper
 Contents
Installation and Setup
Wrappers
Utility
Tool
Wolfram Alpha Wrapper#
This page covers how to use the Wolfram Alpha API within LangChain.
It is broken into two parts: installation and setup, and then references to specific Wolfram Alpha wrappers.
Installation and Setup#
Install requirements with pip install wolframalpha
Go to wolfram alpha and sign up for a developer account here
Create an app and get your APP ID
Set your APP ID as an environment variable WOLFRAM_ALPHA_APPID
Wrappers#
Utility#
There exists a WolframAlphaAPIWrapper utility which wraps this API. To import this utility:
from langchain.utilities.wolfram_alpha import WolframAlphaAPIWrapper
For a more detailed walkthrough of this wrapper, see this notebook.
Tool#
You can also easily load this wrapper as a Tool (to use with an Agent).
You can do this with:
from langchain.agents import load_tools
tools = load_tools(["wolfram-alpha"])
For more information on this, see this page
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Weaviate
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Writer
 Contents

Installation and Setup
Wrappers
Utility
Tool
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Writer
 Contents
Installation and Setup
Wrappers
LLM
Writer#
This page covers how to use the Writer ecosystem within LangChain.
It is broken into two parts: installation and setup, and then references to specific Writer wrappers.
Installation and Setup#
Get an Writer api key and set it as an environment variable (WRITER_API_KEY)
Wrappers#
LLM#
There exists an Writer LLM wrapper, which you can access with
from langchain.llms import Writer
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Wolfram Alpha Wrapper
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Yeager.ai
 Contents

Installation and Setup
Wrappers
LLM
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Yeager.ai
 Contents
What is Yeager.ai?
yAgents
How to use?
Creating and Executing Tools with yAgents
Yeager.ai#
This page covers how to use Yeager.ai to generate LangChain tools and agents.
What is Yeager.ai?#
Yeager.ai is an ecosystem designed to simplify the process of creating AI agents and tools.
It features yAgents, a No-code LangChain Agent Builder, which enables users to build, test, and deploy AI solutions with ease. Leveraging the LangChain framework, yAgents allows seamless integration with various language models and resources, making it suitable for developers, researchers, and AI enthusiasts across diverse applications.
yAgents#
Low code generative agent designed to help you build, prototype, and deploy Langchain tools with ease.
How to use?#
pip install yeagerai-agent
yeagerai-agent
Go to http://127.0.0.1:7860
This will install the necessary dependencies and set up yAgents on your system. After the first run, yAgents will create a .env file where you can input your OpenAI API key. You can do the same directly from the Gradio interface under the tab “Settings”.
OPENAI_API_KEY=<your_openai_api_key_here>
We recommend using GPT-4,. However, the tool can also work with GPT-3 if the problem is broken down sufficiently.
Creating and Executing Tools with yAgents#
yAgents makes it easy to create and execute AI-powered tools. Here’s a brief overview of the process:
Create a tool: To create a tool, provide a natural language prompt to yAgents. The prompt should clearly describe the tool’s purpose and functionality. For example:
create a tool that returns the n-th prime number


create a tool that returns the n-th prime number
Load the tool into the toolkit: To load a tool into yAgents, simply provide a command to yAgents that says so. For example:
load the tool that you just created it into your toolkit
Execute the tool: To run a tool or agent, simply provide a command to yAgents that includes the name of the tool and any required parameters. For example:
generate the 50th prime number
You can see a video of how it works here.
As you become more familiar with yAgents, you can create more advanced tools and agents to automate your work and enhance your productivity.
For more information, see yAgents’ Github or our docs
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Writer
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Zilliz
 Contents

What is Yeager.ai?
yAgents
How to use?
Creating and Executing Tools with yAgents
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Zilliz
 Contents
Installation and Setup
Wrappers
VectorStore
Zilliz#
This page covers how to use the Zilliz Cloud ecosystem within LangChain.
Zilliz uses the Milvus integration.
It is broken into two parts: installation and setup, and then references to specific Milvus wrappers.
Installation and Setup#
Install the Python SDK with pip install pymilvus
Wrappers#
VectorStore#
There exists a wrapper around Zilliz indexes, allowing you to use it as a vectorstore,
whether for semantic search or example selection.
To import this vectorstore:
from langchain.vectorstores import Milvus
For a more detailed walkthrough of the Miluvs wrapper, see this notebook
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Yeager.ai
next
Glossary
 Contents

Installation and Setup
Wrappers
VectorStore
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.md
.pdf
Quickstart Guide
 Contents
Installation
Environment Setup
Building a Language Model Application: LLMs
LLMs: Get predictions from a language model
Prompt Templates: Manage prompts for LLMs
Chains: Combine LLMs and prompts in multi-step workflows
Agents: Dynamically Call Chains Based on User Input
Memory: Add State to Chains and Agents
Building a Language Model Application: Chat Models
Get Message Completions from a Chat Model
Chat Prompt Templates
Chains with Chat Models
Agents with Chat Models
Memory: Add State to Chains and Agents
Quickstart Guide#
This tutorial gives you a quick walkthrough about building an end-to-end language model application with LangChain.
Installation#
To get started, install LangChain with the following command:
pip install langchain
# or
conda install langchain -c conda-forge
Environment Setup#
Using LangChain will usually require integrations with one or more model providers, data stores, apis, etc.
For this example, we will be using OpenAI’s APIs, so we will first need to install their SDK:
pip install openai
We will then need to set the environment variable in the terminal.
export OPENAI_API_KEY="..."
Alternatively, you could do this from inside the Jupyter notebook (or Python script):
import os
os.environ["OPENAI_API_KEY"] = "..."
Building a Language Model Application: LLMs#
Now that we have installed LangChain and set up our environment, we can start building our language model application.
LangChain provides many modules that can be used to build language model applications. Modules can be combined to create more complex applications, or be used individually for simple applications.
LLMs: Get predictions from a language model#
The most basic building block of LangChain is calling an LLM on some input.


The most basic building block of LangChain is calling an LLM on some input.
Let’s walk through a simple example of how to do this.
For this purpose, let’s pretend we are building a service that generates a company name based on what the company makes.
In order to do this, we first need to import the LLM wrapper.
from langchain.llms import OpenAI
We can then initialize the wrapper with any arguments.
In this example, we probably want the outputs to be MORE random, so we’ll initialize it with a HIGH temperature.
llm = OpenAI(temperature=0.9)
We can now call it on some input!
text = "What would be a good company name for a company that makes colorful socks?"
print(llm(text))
Feetful of Fun
For more details on how to use LLMs within LangChain, see the LLM getting started guide.
Prompt Templates: Manage prompts for LLMs#
Calling an LLM is a great first step, but it’s just the beginning.
Normally when you use an LLM in an application, you are not sending user input directly to the LLM.
Instead, you are probably taking user input and constructing a prompt, and then sending that to the LLM.
For example, in the previous example, the text we passed in was hardcoded to ask for a name for a company that made colorful socks.
In this imaginary service, what we would want to do is take only the user input describing what the company does, and then format the prompt with that information.
This is easy to do with LangChain!
First lets define the prompt template:
from langchain.prompts import PromptTemplate
prompt = PromptTemplate(
    input_variables=["product"],
    template="What is a good name for a company that makes {product}?",
)


template="What is a good name for a company that makes {product}?",
)
Let’s now see how this works! We can call the .format method to format it.
print(prompt.format(product="colorful socks"))
What is a good name for a company that makes colorful socks?
For more details, check out the getting started guide for prompts.
Chains: Combine LLMs and prompts in multi-step workflows#
Up until now, we’ve worked with the PromptTemplate and LLM primitives by themselves. But of course, a real application is not just one primitive, but rather a combination of them.
A chain in LangChain is made up of links, which can be either primitives like LLMs or other chains.
The most core type of chain is an LLMChain, which consists of a PromptTemplate and an LLM.
Extending the previous example, we can construct an LLMChain which takes user input, formats it with a PromptTemplate, and then passes the formatted response to an LLM.
from langchain.prompts import PromptTemplate
from langchain.llms import OpenAI
llm = OpenAI(temperature=0.9)
prompt = PromptTemplate(
    input_variables=["product"],
    template="What is a good name for a company that makes {product}?",
)
We can now create a very simple chain that will take user input, format the prompt with it, and then send it to the LLM:
from langchain.chains import LLMChain
chain = LLMChain(llm=llm, prompt=prompt)
Now we can run that chain only specifying the product!
chain.run("colorful socks")
# -> '\n\nSocktastic!'
There we go! There’s the first chain - an LLM Chain.


There we go! There’s the first chain - an LLM Chain.
This is one of the simpler types of chains, but understanding how it works will set you up well for working with more complex chains.
For more details, check out the getting started guide for chains.
Agents: Dynamically Call Chains Based on User Input#
So far the chains we’ve looked at run in a predetermined order.
Agents no longer do: they use an LLM to determine which actions to take and in what order. An action can either be using a tool and observing its output, or returning to the user.
When used correctly agents can be extremely powerful. In this tutorial, we show you how to easily use agents through the simplest, highest level API.
In order to load agents, you should understand the following concepts:
Tool: A function that performs a specific duty. This can be things like: Google Search, Database lookup, Python REPL, other chains. The interface for a tool is currently a function that is expected to have a string as an input, with a string as an output.
LLM: The language model powering the agent.
Agent: The agent to use. This should be a string that references a support agent class. Because this notebook focuses on the simplest, highest level API, this only covers using the standard supported agents. If you want to implement a custom agent, see the documentation for custom agents (coming soon).
Agents: For a list of supported agents and their specifications, see here.
Tools: For a list of predefined tools and their specifications, see here.
For this example, you will also need to install the SerpAPI Python package.
pip install google-search-results
And set the appropriate environment variables.
import os
os.environ["SERPAPI_API_KEY"] = "..."
Now we can get started!
from langchain.agents import load_tools


Now we can get started!
from langchain.agents import load_tools
from langchain.agents import initialize_agent
from langchain.agents import AgentType
from langchain.llms import OpenAI
# First, let's load the language model we're going to use to control the agent.
llm = OpenAI(temperature=0)
# Next, let's load some tools to use. Note that the `llm-math` tool uses an LLM, so we need to pass that in.
tools = load_tools(["serpapi", "llm-math"], llm=llm)
# Finally, let's initialize an agent with the tools, the language model, and the type of agent we want to use.
agent = initialize_agent(tools, llm, agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION, verbose=True)
# Now let's test it out!
agent.run("What was the high temperature in SF yesterday in Fahrenheit? What is that number raised to the .023 power?")
> Entering new AgentExecutor chain...
 I need to find the temperature first, then use the calculator to raise it to the .023 power.
Action: Search
Action Input: "High temperature in SF yesterday"
Observation: San Francisco Temperature Yesterday. Maximum temperature yesterday: 57 °F (at 1:56 pm) Minimum temperature yesterday: 49 °F (at 1:56 am) Average temperature ...
Thought: I now have the temperature, so I can use the calculator to raise it to the .023 power.
Action: Calculator
Action Input: 57^.023
Observation: Answer: 1.0974509573251117
Thought: I now know the final answer
Final Answer: The high temperature in SF yesterday in Fahrenheit raised to the .023 power is 1.0974509573251117.


> Finished chain.
Memory: Add State to Chains and Agents#
So far, all the chains and agents we’ve gone through have been stateless. But often, you may want a chain or agent to have some concept of “memory” so that it may remember information about its previous interactions. The clearest and simple example of this is when designing a chatbot - you want it to remember previous messages so it can use context from that to have a better conversation. This would be a type of “short-term memory”. On the more complex side, you could imagine a chain/agent remembering key pieces of information over time - this would be a form of “long-term memory”. For more concrete ideas on the latter, see this awesome paper.
LangChain provides several specially created chains just for this purpose. This notebook walks through using one of those chains (the ConversationChain) with two different types of memory.
By default, the ConversationChain has a simple type of memory that remembers all previous inputs/outputs and adds them to the context that is passed. Let’s take a look at using this chain (setting verbose=True so we can see the prompt).
from langchain import OpenAI, ConversationChain
llm = OpenAI(temperature=0)
conversation = ConversationChain(llm=llm, verbose=True)
output = conversation.predict(input="Hi there!")
print(output)
> Entering new chain...
Prompt after formatting:
The following is a friendly conversation between a human and an AI. The AI is talkative and provides lots of specific details from its context. If the AI does not know the answer to a question, it truthfully says it does not know.
Current conversation:
Human: Hi there!
AI:
> Finished chain.
' Hello! How are you today?'
output = conversation.predict(input="I'm doing well! Just having a conversation with an AI.")
print(output)


print(output)
> Entering new chain...
Prompt after formatting:
The following is a friendly conversation between a human and an AI. The AI is talkative and provides lots of specific details from its context. If the AI does not know the answer to a question, it truthfully says it does not know.
Current conversation:
Human: Hi there!
AI:  Hello! How are you today?
Human: I'm doing well! Just having a conversation with an AI.
AI:
> Finished chain.
" That's great! What would you like to talk about?"
Building a Language Model Application: Chat Models#
Similarly, you can use chat models instead of LLMs. Chat models are a variation on language models. While chat models use language models under the hood, the interface they expose is a bit different: rather than expose a “text in, text out” API, they expose an interface where “chat messages” are the inputs and outputs.
Chat model APIs are fairly new, so we are still figuring out the correct abstractions.
Get Message Completions from a Chat Model#
You can get chat completions by passing one or more messages to the chat model. The response will be a message. The types of messages currently supported in LangChain are AIMessage, HumanMessage, SystemMessage, and ChatMessage – ChatMessage takes in an arbitrary role parameter. Most of the time, you’ll just be dealing with HumanMessage, AIMessage, and SystemMessage.
from langchain.chat_models import ChatOpenAI
from langchain.schema import (
    AIMessage,
    HumanMessage,
    SystemMessage
)
chat = ChatOpenAI(temperature=0)
You can get completions by passing in a single message.
chat([HumanMessage(content="Translate this sentence from English to French. I love programming.")])


chat([HumanMessage(content="Translate this sentence from English to French. I love programming.")])
# -> AIMessage(content="J'aime programmer.", additional_kwargs={})
You can also pass in multiple messages for OpenAI’s gpt-3.5-turbo and gpt-4 models.
messages = [
    SystemMessage(content="You are a helpful assistant that translates English to French."),
    HumanMessage(content="Translate this sentence from English to French. I love programming.")
]
chat(messages)
# -> AIMessage(content="J'aime programmer.", additional_kwargs={})
You can go one step further and generate completions for multiple sets of messages using generate. This returns an LLMResult with an additional message parameter:
batch_messages = [
    [
        SystemMessage(content="You are a helpful assistant that translates English to French."),
        HumanMessage(content="Translate this sentence from English to French. I love programming.")
    ],
    [
        SystemMessage(content="You are a helpful assistant that translates English to French."),
        HumanMessage(content="Translate this sentence from English to French. I love artificial intelligence.")
    ],
]
result = chat.generate(batch_messages)
result
# -> LLMResult(generations=[[ChatGeneration(text="J'aime programmer.", generation_info=None, message=AIMessage(content="J'aime programmer.", additional_kwargs={}))], [ChatGeneration(text="J'aime l'intelligence artificielle.", generation_info=None, message=AIMessage(content="J'aime l'intelligence artificielle.", additional_kwargs={}))]], llm_output={'token_usage': {'prompt_tokens': 71, 'completion_tokens': 18, 'total_tokens': 89}})
You can recover things like token usage from this LLMResult:
result.llm_output['token_usage']


result.llm_output['token_usage']
# -> {'prompt_tokens': 71, 'completion_tokens': 18, 'total_tokens': 89}
Chat Prompt Templates#
Similar to LLMs, you can make use of templating by using a MessagePromptTemplate. You can build a ChatPromptTemplate from one or more MessagePromptTemplates. You can use ChatPromptTemplate’s format_prompt – this returns a PromptValue, which you can convert to a string or Message object, depending on whether you want to use the formatted value as input to an llm or chat model.
For convience, there is a from_template method exposed on the template. If you were to use this template, this is what it would look like:
from langchain.chat_models import ChatOpenAI
from langchain.prompts.chat import (
    ChatPromptTemplate,
    SystemMessagePromptTemplate,
    HumanMessagePromptTemplate,
)
chat = ChatOpenAI(temperature=0)
template="You are a helpful assistant that translates {input_language} to {output_language}."
system_message_prompt = SystemMessagePromptTemplate.from_template(template)
human_template="{text}"
human_message_prompt = HumanMessagePromptTemplate.from_template(human_template)
chat_prompt = ChatPromptTemplate.from_messages([system_message_prompt, human_message_prompt])
# get a chat completion from the formatted messages
chat(chat_prompt.format_prompt(input_language="English", output_language="French", text="I love programming.").to_messages())
# -> AIMessage(content="J'aime programmer.", additional_kwargs={})
Chains with Chat Models#
The LLMChain discussed in the above section can be used with chat models as well:
from langchain.chat_models import ChatOpenAI
from langchain import LLMChain
from langchain.prompts.chat import (
    ChatPromptTemplate,
    SystemMessagePromptTemplate,


ChatPromptTemplate,
    SystemMessagePromptTemplate,
    HumanMessagePromptTemplate,
)
chat = ChatOpenAI(temperature=0)
template="You are a helpful assistant that translates {input_language} to {output_language}."
system_message_prompt = SystemMessagePromptTemplate.from_template(template)
human_template="{text}"
human_message_prompt = HumanMessagePromptTemplate.from_template(human_template)
chat_prompt = ChatPromptTemplate.from_messages([system_message_prompt, human_message_prompt])
chain = LLMChain(llm=chat, prompt=chat_prompt)
chain.run(input_language="English", output_language="French", text="I love programming.")
# -> "J'aime programmer."
Agents with Chat Models#
Agents can also be used with chat models, you can initialize one using AgentType.CHAT_ZERO_SHOT_REACT_DESCRIPTION as the agent type.
from langchain.agents import load_tools
from langchain.agents import initialize_agent
from langchain.agents import AgentType
from langchain.chat_models import ChatOpenAI
from langchain.llms import OpenAI
# First, let's load the language model we're going to use to control the agent.
chat = ChatOpenAI(temperature=0)
# Next, let's load some tools to use. Note that the `llm-math` tool uses an LLM, so we need to pass that in.
llm = OpenAI(temperature=0)
tools = load_tools(["serpapi", "llm-math"], llm=llm)
# Finally, let's initialize an agent with the tools, the language model, and the type of agent we want to use.
agent = initialize_agent(tools, chat, agent=AgentType.CHAT_ZERO_SHOT_REACT_DESCRIPTION, verbose=True)
# Now let's test it out!


# Now let's test it out!
agent.run("Who is Olivia Wilde's boyfriend? What is his current age raised to the 0.23 power?")
> Entering new AgentExecutor chain...
Thought: I need to use a search engine to find Olivia Wilde's boyfriend and a calculator to raise his age to the 0.23 power.
Action:
{
  "action": "Search",
  "action_input": "Olivia Wilde boyfriend"
}
Observation: Sudeikis and Wilde's relationship ended in November 2020. Wilde was publicly served with court documents regarding child custody while she was presenting Don't Worry Darling at CinemaCon 2022. In January 2021, Wilde began dating singer Harry Styles after meeting during the filming of Don't Worry Darling.
Thought:I need to use a search engine to find Harry Styles' current age.
Action:
{
  "action": "Search",
  "action_input": "Harry Styles age"
}
Observation: 29 years
Thought:Now I need to calculate 29 raised to the 0.23 power.
Action:
{
  "action": "Calculator",
  "action_input": "29^0.23"
}
Observation: Answer: 2.169459462491557
Thought:I now know the final answer.
Final Answer: 2.169459462491557
> Finished chain.
'2.169459462491557'
Memory: Add State to Chains and Agents#
You can use Memory with chains and agents initialized with chat models. The main difference between this and Memory for LLMs is that rather than trying to condense all previous messages into a string, we can keep them as their own unique memory object.
from langchain.prompts import (
    ChatPromptTemplate,
    MessagesPlaceholder,


ChatPromptTemplate,
    MessagesPlaceholder,
    SystemMessagePromptTemplate,
    HumanMessagePromptTemplate
)
from langchain.chains import ConversationChain
from langchain.chat_models import ChatOpenAI
from langchain.memory import ConversationBufferMemory
prompt = ChatPromptTemplate.from_messages([
    SystemMessagePromptTemplate.from_template("The following is a friendly conversation between a human and an AI. The AI is talkative and provides lots of specific details from its context. If the AI does not know the answer to a question, it truthfully says it does not know."),
    MessagesPlaceholder(variable_name="history"),
    HumanMessagePromptTemplate.from_template("{input}")
])
llm = ChatOpenAI(temperature=0)
memory = ConversationBufferMemory(return_messages=True)
conversation = ConversationChain(memory=memory, prompt=prompt, llm=llm)
conversation.predict(input="Hi there!")
# -> 'Hello! How can I assist you today?'
conversation.predict(input="I'm doing well! Just having a conversation with an AI.")
# -> "That sounds like fun! I'm happy to chat with you. Is there anything specific you'd like to talk about?"
conversation.predict(input="Tell me about yourself.")
# -> "Sure! I am an AI language model created by OpenAI. I was trained on a large dataset of text from the internet, which allows me to understand and generate human-like language. I can answer questions, provide information, and even have conversations like this one. Is there anything else you'd like to know about me?"
previous
Welcome to LangChain
next
Models
 Contents

Installation
Environment Setup
Building a Language Model Application: LLMs
LLMs: Get predictions from a language model
Prompt Templates: Manage prompts for LLMs
Chains: Combine LLMs and prompts in multi-step workflows


Chains: Combine LLMs and prompts in multi-step workflows
Agents: Dynamically Call Chains Based on User Input
Memory: Add State to Chains and Agents
Building a Language Model Application: Chat Models
Get Message Completions from a Chat Model
Chat Prompt Templates
Chains with Chat Models
Agents with Chat Models
Memory: Add State to Chains and Agents
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.rst
.pdf
Agents
 Contents
Go Deeper
Agents#
Note
Conceptual Guide
Some applications will require not just a predetermined chain of calls to LLMs/other tools,
but potentially an unknown chain that depends on the user’s input.
In these types of chains, there is a “agent” which has access to a suite of tools.
Depending on the user input, the agent can then decide which, if any, of these tools to call.
In this section of documentation, we first start with a Getting Started notebook to cover how to use all things related to agents in an end-to-end manner.
We then split the documentation into the following sections:
Tools
An overview of the various tools LangChain supports.
Agents
An overview of the different agent types.
Toolkits
An overview of toolkits, and examples of the different ones LangChain supports.
Agent Executor
An overview of the Agent Executor class and examples of how to use it.
Go Deeper#
Tools
Agents
Toolkits
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By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.rst
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Chains
Chains#
Note
Conceptual Guide
Using an LLM in isolation is fine for some simple applications,
but many more complex ones require chaining LLMs - either with each other or with other experts.
LangChain provides a standard interface for Chains, as well as some common implementations of chains for ease of use.
The following sections of documentation are provided:
Getting Started: A getting started guide for chains, to get you up and running quickly.
How-To Guides: A collection of how-to guides. These highlight how to use various types of chains.
Reference: API reference documentation for all Chain classes.
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Redis Chat Message History
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Getting Started
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


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Indexes
 Contents
Go Deeper
Indexes#
Note
Conceptual Guide
Indexes refer to ways to structure documents so that LLMs can best interact with them.
This module contains utility functions for working with documents, different types of indexes, and then examples for using those indexes in chains.
The most common way that indexes are used in chains is in a “retrieval” step.
This step refers to taking a user’s query and returning the most relevant documents.
We draw this distinction because (1) an index can be used for other things besides retrieval, and (2) retrieval can use other logic besides an index to find relevant documents.
We therefore have a concept of a “Retriever” interface - this is the interface that most chains work with.
Most of the time when we talk about indexes and retrieval we are talking about indexing and retrieving unstructured data (like text documents).
For interacting with structured data (SQL tables, etc) or APIs, please see the corresponding use case sections for links to relevant functionality.
The primary index and retrieval types supported by LangChain are currently centered around vector databases, and therefore
a lot of the functionality we dive deep on those topics.
For an overview of everything related to this, please see the below notebook for getting started:
Getting Started
We then provide a deep dive on the four main components.
Document Loaders
How to load documents from a variety of sources.
Text Splitters
An overview of the abstractions and implementions around splitting text.
VectorStores
An overview of VectorStores and the many integrations LangChain provides.
Retrievers
An overview of Retrievers and the implementations LangChain provides.
Go Deeper#
Document Loaders
Text Splitters
Vectorstores
Retrievers
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Structured Output Parser
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Structured Output Parser
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Getting Started
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Go Deeper
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.rst
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Memory
Memory#
Note
Conceptual Guide
By default, Chains and Agents are stateless,
meaning that they treat each incoming query independently (as are the underlying LLMs and chat models).
In some applications (chatbots being a GREAT example) it is highly important
to remember previous interactions, both at a short term but also at a long term level.
The concept of “Memory” exists to do exactly that.
LangChain provides memory components in two forms.
First, LangChain provides helper utilities for managing and manipulating previous chat messages.
These are designed to be modular and useful regardless of how they are used.
Secondly, LangChain provides easy ways to incorporate these utilities into chains.
The following sections of documentation are provided:
Getting Started: An overview of how to get started with different types of memory.
How-To Guides: A collection of how-to guides. These highlight different types of memory, as well as how to use memory in chains.
Memory
Getting Started
How-To Guides
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By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


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Models
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Go Deeper
Models#
Note
Conceptual Guide
This section of the documentation deals with different types of models that are used in LangChain.
On this page we will go over the model types at a high level,
but we have individual pages for each model type.
The pages contain more detailed “how-to” guides for working with that model,
as well as a list of different model providers.
LLMs
Large Language Models (LLMs) are the first type of models we cover.
These models take a text string as input, and return a text string as output.
Chat Models
Chat Models are the second type of models we cover.
These models are usually backed by a language model, but their APIs are more structured.
Specifically, these models take a list of Chat Messages as input, and return a Chat Message.
Text Embedding Models
The third type of models we cover are text embedding models.
These models take text as input and return a list of floats.
Go Deeper#
LLMs
Chat Models
Text Embedding Models
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Quickstart Guide
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LLMs
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By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


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Prompts
 Contents
Go Deeper
Prompts#
Note
Conceptual Guide
The new way of programming models is through prompts.
A “prompt” refers to the input to the model.
This input is rarely hard coded, but rather is often constructed from multiple components.
A PromptTemplate is responsible for the construction of this input.
LangChain provides several classes and functions to make constructing and working with prompts easy.
This section of documentation is split into four sections:
LLM Prompt Templates
How to use PromptTemplates to prompt Language Models.
Chat Prompt Templates
How to use PromptTemplates to prompt Chat Models.
Example Selectors
Often times it is useful to include examples in prompts.
These examples can be hardcoded, but it is often more powerful if they are dynamically selected.
This section goes over example selection.
Output Parsers
Language models (and Chat Models) output text.
But many times you may want to get more structured information than just text back.
This is where output parsers come in.
Output Parsers are responsible for (1) instructing the model how output should be formatted,
(2) parsing output into the desired formatting (including retrying if necessary).
Go Deeper#
Prompt Templates
Chat Prompt Template
Example Selectors
Output Parsers
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By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.rst
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Agents
Agents#
Note
Conceptual Guide
In this part of the documentation we cover the different types of agents, disregarding which specific tools they are used with.
For a high level overview of the different types of agents, see the below documentation.
Agent Types
For documentation on how to create a custom agent, see the below.
Custom Agent
Custom LLM Agent
Custom LLM Agent (with a ChatModel)
Custom MRKL Agent
Custom MultiAction Agent
Custom Agent with Tool Retrieval
We also have documentation for an in-depth dive into each agent type.
Conversation Agent (for Chat Models)
Conversation Agent
MRKL
MRKL Chat
ReAct
Self Ask With Search
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Zapier Natural Language Actions API
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Agent Types
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


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Agent Executors
Agent Executors#
Note
Conceptual Guide
Agent executors take an agent and tools and use the agent to decide which tools to call and in what order.
In this part of the documentation we cover other related functionality to agent executors
How to combine agents and vectorstores
How to use the async API for Agents
How to create ChatGPT Clone
How to access intermediate steps
How to cap the max number of iterations
How to use a timeout for the agent
How to add SharedMemory to an Agent and its Tools
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Vectorstore Agent
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How to combine agents and vectorstores
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


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Getting Started
Getting Started#
Agents use an LLM to determine which actions to take and in what order.
An action can either be using a tool and observing its output, or returning to the user.
When used correctly agents can be extremely powerful. The purpose of this notebook is to show you how to easily use agents through the simplest, highest level API.
In order to load agents, you should understand the following concepts:
Tool: A function that performs a specific duty. This can be things like: Google Search, Database lookup, Python REPL, other chains. The interface for a tool is currently a function that is expected to have a string as an input, with a string as an output.
LLM: The language model powering the agent.
Agent: The agent to use. This should be a string that references a support agent class. Because this notebook focuses on the simplest, highest level API, this only covers using the standard supported agents. If you want to implement a custom agent, see the documentation for custom agents (coming soon).
Agents: For a list of supported agents and their specifications, see here.
Tools: For a list of predefined tools and their specifications, see here.
from langchain.agents import load_tools
from langchain.agents import initialize_agent
from langchain.agents import AgentType
from langchain.llms import OpenAI
First, let’s load the language model we’re going to use to control the agent.
llm = OpenAI(temperature=0)
Next, let’s load some tools to use. Note that the llm-math tool uses an LLM, so we need to pass that in.
tools = load_tools(["serpapi", "llm-math"], llm=llm)
Finally, let’s initialize an agent with the tools, the language model, and the type of agent we want to use.


agent = initialize_agent(tools, llm, agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION, verbose=True)
Now let’s test it out!
agent.run("Who is Leo DiCaprio's girlfriend? What is her current age raised to the 0.43 power?")
> Entering new AgentExecutor chain...
 I need to find out who Leo DiCaprio's girlfriend is and then calculate her age raised to the 0.43 power.
Action: Search
Action Input: "Leo DiCaprio girlfriend"
Observation: Camila Morrone
Thought: I need to find out Camila Morrone's age
Action: Search
Action Input: "Camila Morrone age"
Observation: 25 years
Thought: I need to calculate 25 raised to the 0.43 power
Action: Calculator
Action Input: 25^0.43
Observation: Answer: 3.991298452658078
Thought: I now know the final answer
Final Answer: Camila Morrone is Leo DiCaprio's girlfriend and her current age raised to the 0.43 power is 3.991298452658078.
> Finished chain.
"Camila Morrone is Leo DiCaprio's girlfriend and her current age raised to the 0.43 power is 3.991298452658078."
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Agents
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Tools
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.rst
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Toolkits
Toolkits#
Note
Conceptual Guide
This section of documentation covers agents with toolkits - eg an agent applied to a particular use case.
See below for a full list of agent toolkits
CSV Agent
Jira
JSON Agent
OpenAPI agents
Natural Language APIs
Pandas Dataframe Agent
PowerBI Dataset Agent
Python Agent
SQL Database Agent
Vectorstore Agent
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Self Ask With Search
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CSV Agent
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


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Tools
Tools#
Note
Conceptual Guide
Tools are ways that an agent can use to interact with the outside world.
For an overview of what a tool is, how to use them, and a full list of examples, please see the getting started documentation
Getting Started
Next, we have some examples of customizing and generically working with tools
Defining Custom Tools
Multi-Input Tools
Tool Input Schema
In this documentation we cover generic tooling functionality (eg how to create your own)
as well as examples of tools and how to use them.
Apify
Arxiv API
Bash
Bing Search
ChatGPT Plugins
DuckDuckGo Search
Google Places
Google Search
Google Serper API
Gradio Tools
Human as a tool
IFTTT WebHooks
OpenWeatherMap API
Python REPL
Requests
Search Tools
SearxNG Search API
SerpAPI
Wikipedia API
Wolfram Alpha
Zapier Natural Language Actions API
Example with SimpleSequentialChain
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Getting Started
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Getting Started
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


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Agent Types
 Contents
zero-shot-react-description
react-docstore
self-ask-with-search
conversational-react-description
Agent Types#
Agents use an LLM to determine which actions to take and in what order.
An action can either be using a tool and observing its output, or returning a response to the user.
Here are the agents available in LangChain.
zero-shot-react-description#
This agent uses the ReAct framework to determine which tool to use
based solely on the tool’s description. Any number of tools can be provided.
This agent requires that a description is provided for each tool.
react-docstore#
This agent uses the ReAct framework to interact with a docstore. Two tools must
be provided: a Search tool and a Lookup tool (they must be named exactly as so).
The Search tool should search for a document, while the Lookup tool should lookup
a term in the most recently found document.
This agent is equivalent to the
original ReAct paper, specifically the Wikipedia example.
self-ask-with-search#
This agent utilizes a single tool that should be named Intermediate Answer.
This tool should be able to lookup factual answers to questions. This agent
is equivalent to the original self ask with search paper,
where a Google search API was provided as the tool.
conversational-react-description#
This agent is designed to be used in conversational settings.
The prompt is designed to make the agent helpful and conversational.
It uses the ReAct framework to decide which tool to use, and uses memory to remember the previous conversation interactions.
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Agents
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Custom Agent
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zero-shot-react-description
react-docstore
self-ask-with-search
conversational-react-description
By Harrison Chase

      © Copyright 2023, Harrison Chase.


By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Apr 25, 2023.


.ipynb
.pdf
Custom Agent
Custom Agent#
This notebook goes through how to create your own custom agent.
An agent consists of three parts:
- Tools: The tools the agent has available to use.
- The agent class itself: this decides which action to take.
In this notebook we walk through how to create a custom agent.
from langchain.agents import Tool, AgentExecutor, BaseSingleActionAgent
from langchain import OpenAI, SerpAPIWrapper
search = SerpAPIWrapper()
tools = [
    Tool(
        name = "Search",
        func=search.run,
        description="useful for when you need to answer questions about current events",
        return_direct=True
    )
]
from typing import List, Tuple, Any, Union
from langchain.schema import AgentAction, AgentFinish
class FakeAgent(BaseSingleActionAgent):
    """Fake Custom Agent."""

    @property
    def input_keys(self):
        return ["input"]

    def plan(
        self, intermediate_steps: List[Tuple[AgentAction, str]], **kwargs: Any
    ) -> Union[AgentAction, AgentFinish]:
        """Given input, decided what to do.
        Args:
            intermediate_steps: Steps the LLM has taken to date,
                along with observations
            **kwargs: User inputs.
        Returns:
            Action specifying what tool to use.
        """
        return AgentAction(tool="Search", tool_input=kwargs["input"], log="")
    async def aplan(
        self, intermediate_steps: List[Tuple[AgentAction, str]], **kwargs: Any
    ) -> Union[AgentAction, AgentFinish]:
        """Given input, decided what to do.
        Args:
            intermediate_steps: Steps the LLM has taken to date,