Authors: Parth Asawa (pgasawa@), Ayushi Batwara (ayushi.batwara@), Jason Mar 8, 2023 4 min read Prompt Selectors One common complaint we've heard is that the default prompt templates do not work equally well for all models. This became especially pronounced this past week when OpenAI released a ChatGPT API. This new API had a completely new interface (which required new abstractions) and as a result many users Mar 8, 2023 2 min read Chat Models Last week OpenAI released a ChatGPT endpoint. It came marketed with several big improvements, most notably being 10x cheaper and a lot faster. But it also came with a completely new API endpoint. We were able to quickly write a wrapper for this endpoint to let users use it like Mar 6, 2023 6 min read Using the ChatGPT API to evaluate the ChatGPT API OpenAI released a new ChatGPT API yesterday. Lots of people were excited to try it. But how does it actually compare to the existing API? It will take some time before there is a definitive answer, but here are some initial thoughts. Because I'm lazy, I also enrolled the help Mar 2, 2023 5 min read Agent Toolkits Today, we're announcing agent toolkits, a new abstraction that allows developers to create agents designed for a particular use-case (for example, interacting with a relational database or interacting with an OpenAPI spec). We hope to continue developing different toolkits that can enable agents to do amazing feats. Toolkits are supported Mar 1, 2023 3 min read TypeScript Support It's finally here... TypeScript support for LangChain.


What does this mean? It means that all your favorite prompts, chains, and agents are all recreatable in TypeScript natively. Both the Python version and TypeScript version utilize the same serializable format, meaning that artifacts can seamlessly be shared between languages. As an Feb 17, 2023 2 min read Streaming Support in LangChain We’re excited to announce streaming support in LangChain. There's been a lot of talk about the best UX for LLM applications, and we believe streaming is at its core. We’ve also updated the chat-langchain repo to include streaming and async execution. We hope that this repo can serve Feb 14, 2023 2 min read LangChain + Chroma Today we’re announcing LangChain's integration with Chroma, the first step on the path to the Modern A.I Stack.
LangChain - The A.I-native developer toolkit
We started LangChain with the intent to build a modular and flexible framework for developing A.I-native applications. Some of the use cases Feb 13, 2023 2 min read Page 1 of 2 Older Posts → LangChain © 2023 Sign up Powered by Ghost
Thought:
> Finished chain.
The LangChain blog has recently released an open-source auto-evaluator tool for grading LLM question-answer chains and is now releasing an open-source, free-to-use hosted app and API to expand usability. The blog also discusses various opportunities to further improve the LangChain platform.
response = await agent_chain.arun(input="What's the latest xkcd comic about?")
print(response)
> Entering new AgentExecutor chain...
Thought: I can navigate to the xkcd website and extract the latest comic title and alt text to answer the question.
Action:
```
{
  "action": "navigate_browser",
  "action_input": {
    "url": "https://xkcd.com/"
  }


"url": "https://xkcd.com/"
  }
}
```
Observation: Navigating to https://xkcd.com/ returned status code 200
Thought:I can extract the latest comic title and alt text using CSS selectors.
Action:
```
{
  "action": "get_elements",
  "action_input": {
    "selector": "#ctitle, #comic img",
    "attributes": ["alt", "src"]
  }
}
```
Observation: [{"alt": "Tapetum Lucidum", "src": "//imgs.xkcd.com/comics/tapetum_lucidum.png"}]
Thought:
> Finished chain.
The latest xkcd comic is titled "Tapetum Lucidum" and the image can be found at https://xkcd.com/2565/.
Adding in memory#
Here is how you add in memory to this agent
from langchain.prompts import MessagesPlaceholder
from langchain.memory import ConversationBufferMemory
chat_history = MessagesPlaceholder(variable_name="chat_history")
memory = ConversationBufferMemory(memory_key="chat_history", return_messages=True)
agent_chain = initialize_agent(
    tools,
    llm,
    agent=AgentType.STRUCTURED_CHAT_ZERO_SHOT_REACT_DESCRIPTION,
    verbose=True,
    memory=memory,
    agent_kwargs = {
        "memory_prompts": [chat_history],
        "input_variables": ["input", "agent_scratchpad", "chat_history"]
    }
)
response = await agent_chain.arun(input="Hi I'm Erica.")
print(response)
> Entering new AgentExecutor chain...
Action:
```
{
  "action": "Final Answer",


Action:
```
{
  "action": "Final Answer",
  "action_input": "Hi Erica! How can I assist you today?"
}
```
> Finished chain.
Hi Erica! How can I assist you today?
response = await agent_chain.arun(input="whats my name?")
print(response)
> Entering new AgentExecutor chain...
Your name is Erica.
> Finished chain.
Your name is Erica.
previous
Self Ask With Search
next
Toolkits
 Contents

Initialize Tools
Adding in memory
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
MRKL
MRKL#
This notebook showcases using an agent to replicate the MRKL chain.
This uses the example Chinook database.
To set it up follow the instructions on https://database.guide/2-sample-databases-sqlite/, placing the .db file in a notebooks folder at the root of this repository.
from langchain import LLMMathChain, OpenAI, SerpAPIWrapper, SQLDatabase, SQLDatabaseChain
from langchain.agents import initialize_agent, Tool
from langchain.agents import AgentType
llm = OpenAI(temperature=0)
search = SerpAPIWrapper()
llm_math_chain = LLMMathChain(llm=llm, verbose=True)
db = SQLDatabase.from_uri("sqlite:///../../../../../notebooks/Chinook.db")
db_chain = SQLDatabaseChain.from_llm(llm, db, verbose=True)
tools = [
    Tool(
        name = "Search",
        func=search.run,
        description="useful for when you need to answer questions about current events. You should ask targeted questions"
    ),
    Tool(
        name="Calculator",
        func=llm_math_chain.run,
        description="useful for when you need to answer questions about math"
    ),
    Tool(
        name="FooBar DB",
        func=db_chain.run,
        description="useful for when you need to answer questions about FooBar. Input should be in the form of a question containing full context"
    )
]
mrkl = initialize_agent(tools, llm, agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION, verbose=True)
mrkl.run("Who is Leo DiCaprio's girlfriend? What is her current age raised to the 0.43 power?")
> Entering new AgentExecutor chain...


> 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: "Who is Leo DiCaprio's girlfriend?"
Observation: DiCaprio met actor Camila Morrone in December 2017, when she was 20 and he was 43. They were spotted at Coachella and went on multiple vacations together. Some reports suggested that DiCaprio was ready to ask Morrone to marry him. The couple made their red carpet debut at the 2020 Academy Awards.
Thought: I need to calculate Camila Morrone's age raised to the 0.43 power.
Action: Calculator
Action Input: 21^0.43
> Entering new LLMMathChain chain...
21^0.43
```text
21**0.43
```
...numexpr.evaluate("21**0.43")...
Answer: 3.7030049853137306
> Finished chain.
Observation: Answer: 3.7030049853137306
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 3.7030049853137306.
> Finished chain.
"Camila Morrone is Leo DiCaprio's girlfriend and her current age raised to the 0.43 power is 3.7030049853137306."
mrkl.run("What is the full name of the artist who recently released an album called 'The Storm Before the Calm' and are they in the FooBar database? If so, what albums of theirs are in the FooBar database?")
> Entering new AgentExecutor chain...


> Entering new AgentExecutor chain...
 I need to find out the artist's full name and then search the FooBar database for their albums.
Action: Search
Action Input: "The Storm Before the Calm" artist
Observation: The Storm Before the Calm (stylized in all lowercase) is the tenth (and eighth international) studio album by Canadian-American singer-songwriter Alanis Morissette, released June 17, 2022, via Epiphany Music and Thirty Tigers, as well as by RCA Records in Europe.
Thought: I now need to search the FooBar database for Alanis Morissette's albums.
Action: FooBar DB
Action Input: What albums by Alanis Morissette are in the FooBar database?
> Entering new SQLDatabaseChain chain...
What albums by Alanis Morissette are in the FooBar database?
SQLQuery:
/Users/harrisonchase/workplace/langchain/langchain/sql_database.py:191: SAWarning: Dialect sqlite+pysqlite does *not* support Decimal objects natively, and SQLAlchemy must convert from floating point - rounding errors and other issues may occur. Please consider storing Decimal numbers as strings or integers on this platform for lossless storage.
  sample_rows = connection.execute(command)
 SELECT "Title" FROM "Album" INNER JOIN "Artist" ON "Album"."ArtistId" = "Artist"."ArtistId" WHERE "Name" = 'Alanis Morissette' LIMIT 5;
SQLResult: [('Jagged Little Pill',)]
Answer: The albums by Alanis Morissette in the FooBar database are Jagged Little Pill.
> Finished chain.
Observation:  The albums by Alanis Morissette in the FooBar database are Jagged Little Pill.
Thought: I now know the final answer.


Thought: I now know the final answer.
Final Answer: The artist who released the album 'The Storm Before the Calm' is Alanis Morissette and the albums of hers in the FooBar database are Jagged Little Pill.
> Finished chain.
"The artist who released the album 'The Storm Before the Calm' is Alanis Morissette and the albums of hers in the FooBar database are Jagged Little Pill."
previous
Conversation Agent
next
MRKL Chat
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
MRKL Chat
MRKL Chat#
This notebook showcases using an agent to replicate the MRKL chain using an agent optimized for chat models.
This uses the example Chinook database.
To set it up follow the instructions on https://database.guide/2-sample-databases-sqlite/, placing the .db file in a notebooks folder at the root of this repository.
from langchain import OpenAI, LLMMathChain, SerpAPIWrapper, SQLDatabase, SQLDatabaseChain
from langchain.agents import initialize_agent, Tool
from langchain.agents import AgentType
from langchain.chat_models import ChatOpenAI
llm = ChatOpenAI(temperature=0)
llm1 = OpenAI(temperature=0)
search = SerpAPIWrapper()
llm_math_chain = LLMMathChain(llm=llm1, verbose=True)
db = SQLDatabase.from_uri("sqlite:///../../../../../notebooks/Chinook.db")
db_chain = SQLDatabaseChain.from_llm(llm1, db, verbose=True)
tools = [
    Tool(
        name = "Search",
        func=search.run,
        description="useful for when you need to answer questions about current events. You should ask targeted questions"
    ),
    Tool(
        name="Calculator",
        func=llm_math_chain.run,
        description="useful for when you need to answer questions about math"
    ),
    Tool(
        name="FooBar DB",
        func=db_chain.run,
        description="useful for when you need to answer questions about FooBar. Input should be in the form of a question containing full context"
    )
]
mrkl = initialize_agent(tools, llm, agent=AgentType.CHAT_ZERO_SHOT_REACT_DESCRIPTION, verbose=True)


mrkl.run("Who is Leo DiCaprio's girlfriend? What is her current age raised to the 0.43 power?")
> Entering new AgentExecutor chain...
Thought: The first question requires a search, while the second question requires a calculator.
Action:
```
{
  "action": "Search",
  "action_input": "Leo DiCaprio girlfriend"
}
```
Observation: Gigi Hadid: 2022 Leo and Gigi were first linked back in September 2022, when a source told Us Weekly that Leo had his “sights set" on her (alarming way to put it, but okay).
Thought:For the second question, I need to calculate the age raised to the 0.43 power. I will use the calculator tool.
Action:
```
{
  "action": "Calculator",
  "action_input": "((2022-1995)^0.43)"
}
```
> Entering new LLMMathChain chain...
((2022-1995)^0.43)
```text
(2022-1995)**0.43
```
...numexpr.evaluate("(2022-1995)**0.43")...
Answer: 4.125593352125936
> Finished chain.
Observation: Answer: 4.125593352125936
Thought:I now know the final answer.
Final Answer: Gigi Hadid is Leo DiCaprio's girlfriend and her current age raised to the 0.43 power is approximately 4.13.
> Finished chain.
"Gigi Hadid is Leo DiCaprio's girlfriend and her current age raised to the 0.43 power is approximately 4.13."


mrkl.run("What is the full name of the artist who recently released an album called 'The Storm Before the Calm' and are they in the FooBar database? If so, what albums of theirs are in the FooBar database?")
> Entering new AgentExecutor chain...
Question: What is the full name of the artist who recently released an album called 'The Storm Before the Calm' and are they in the FooBar database? If so, what albums of theirs are in the FooBar database?
Thought: I should use the Search tool to find the answer to the first part of the question and then use the FooBar DB tool to find the answer to the second part.
Action:
```
{
  "action": "Search",
  "action_input": "Who recently released an album called 'The Storm Before the Calm'"
}
```
Observation: Alanis Morissette
Thought:Now that I know the artist's name, I can use the FooBar DB tool to find out if they are in the database and what albums of theirs are in it.
Action:
```
{
  "action": "FooBar DB",
  "action_input": "What albums does Alanis Morissette have in the database?"
}
```
> Entering new SQLDatabaseChain chain...
What albums does Alanis Morissette have in the database?
SQLQuery:
/Users/harrisonchase/workplace/langchain/langchain/sql_database.py:191: SAWarning: Dialect sqlite+pysqlite does *not* support Decimal objects natively, and SQLAlchemy must convert from floating point - rounding errors and other issues may occur. Please consider storing Decimal numbers as strings or integers on this platform for lossless storage.
  sample_rows = connection.execute(command)


sample_rows = connection.execute(command)
 SELECT "Title" FROM "Album" WHERE "ArtistId" IN (SELECT "ArtistId" FROM "Artist" WHERE "Name" = 'Alanis Morissette') LIMIT 5;
SQLResult: [('Jagged Little Pill',)]
Answer: Alanis Morissette has the album Jagged Little Pill in the database.
> Finished chain.
Observation:  Alanis Morissette has the album Jagged Little Pill in the database.
Thought:The artist Alanis Morissette is in the FooBar database and has the album Jagged Little Pill in it.
Final Answer: Alanis Morissette is in the FooBar database and has the album Jagged Little Pill in it.
> Finished chain.
'Alanis Morissette is in the FooBar database and has the album Jagged Little Pill in it.'
previous
MRKL
next
OpenAI Functions Agent
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
OpenAI Functions Agent
OpenAI Functions Agent#
This notebook showcases using an agent that uses the OpenAI functions ability
from langchain import LLMMathChain, OpenAI, SerpAPIWrapper, SQLDatabase, SQLDatabaseChain
from langchain.agents import initialize_agent, Tool
from langchain.agents import AgentType
from langchain.chat_models import ChatOpenAI
llm = ChatOpenAI(temperature=0, model="gpt-3.5-turbo-0613")
search = SerpAPIWrapper()
llm_math_chain = LLMMathChain.from_llm(llm=llm, verbose=True)
db = SQLDatabase.from_uri("sqlite:///../../../../../notebooks/Chinook.db")
db_chain = SQLDatabaseChain.from_llm(llm, db, verbose=True)
tools = [
    Tool(
        name = "Search",
        func=search.run,
        description="useful for when you need to answer questions about current events. You should ask targeted questions"
    ),
    Tool(
        name="Calculator",
        func=llm_math_chain.run,
        description="useful for when you need to answer questions about math"
    ),
    Tool(
        name="FooBar-DB",
        func=db_chain.run,
        description="useful for when you need to answer questions about FooBar. Input should be in the form of a question containing full context"
    )
]
mrkl = initialize_agent(tools, llm, agent=AgentType.OPENAI_FUNCTIONS, verbose=True)
mrkl.run("Who is Leo DiCaprio's girlfriend? What is her current age raised to the 0.43 power?")
> Entering new  chain...
Invoking: `Search` with `{'query': 'Leo DiCaprio girlfriend'}`


Invoking: `Search` with `{'query': 'Leo DiCaprio girlfriend'}`
Amidst his casual romance with Gigi, Leo allegedly entered a relationship with 19-year old model, Eden Polani, in February 2023.
Invoking: `Calculator` with `{'expression': '19^0.43'}`
> Entering new  chain...
19^0.43```text
19**0.43
```
...numexpr.evaluate("19**0.43")...
Answer: 3.547023357958959
> Finished chain.
Answer: 3.547023357958959Leo DiCaprio's girlfriend is reportedly Eden Polani. Her current age raised to the power of 0.43 is approximately 3.55.
> Finished chain.
"Leo DiCaprio's girlfriend is reportedly Eden Polani. Her current age raised to the power of 0.43 is approximately 3.55."
previous
MRKL Chat
next
ReAct
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
Conversation Agent
Conversation Agent#
This notebook walks through using an agent optimized for conversation. Other agents are often optimized for using tools to figure out the best response, which is not ideal in a conversational setting where you may want the agent to be able to chat with the user as well.
This is accomplished with a specific type of agent (conversational-react-description) which expects to be used with a memory component.
from langchain.agents import Tool
from langchain.agents import AgentType
from langchain.memory import ConversationBufferMemory
from langchain import OpenAI
from langchain.utilities import SerpAPIWrapper
from langchain.agents import initialize_agent
search = SerpAPIWrapper()
tools = [
    Tool(
        name = "Current Search",
        func=search.run,
        description="useful for when you need to answer questions about current events or the current state of the world"
    ),
]
memory = ConversationBufferMemory(memory_key="chat_history")
llm=OpenAI(temperature=0)
agent_chain = initialize_agent(tools, llm, agent=AgentType.CONVERSATIONAL_REACT_DESCRIPTION, verbose=True, memory=memory)
agent_chain.run(input="hi, i am bob")
> Entering new AgentExecutor chain...
Thought: Do I need to use a tool? No
AI: Hi Bob, nice to meet you! How can I help you today?
> Finished chain.
'Hi Bob, nice to meet you! How can I help you today?'
agent_chain.run(input="what's my name?")
> Entering new AgentExecutor chain...
Thought: Do I need to use a tool? No
AI: Your name is Bob!
> Finished chain.
'Your name is Bob!'


AI: Your name is Bob!
> Finished chain.
'Your name is Bob!'
agent_chain.run("what are some good dinners to make this week, if i like thai food?")
> Entering new AgentExecutor chain...
Thought: Do I need to use a tool? Yes
Action: Current Search
Action Input: Thai food dinner recipes
Observation: 59 easy Thai recipes for any night of the week · Marion Grasby's Thai spicy chilli and basil fried rice · Thai curry noodle soup · Marion Grasby's Thai Spicy ...
Thought: Do I need to use a tool? No
AI: Here are some great Thai dinner recipes you can try this week: Marion Grasby's Thai Spicy Chilli and Basil Fried Rice, Thai Curry Noodle Soup, Thai Green Curry with Coconut Rice, Thai Red Curry with Vegetables, and Thai Coconut Soup. I hope you enjoy them!
> Finished chain.
"Here are some great Thai dinner recipes you can try this week: Marion Grasby's Thai Spicy Chilli and Basil Fried Rice, Thai Curry Noodle Soup, Thai Green Curry with Coconut Rice, Thai Red Curry with Vegetables, and Thai Coconut Soup. I hope you enjoy them!"
agent_chain.run(input="tell me the last letter in my name, and also tell me who won the world cup in 1978?")
> Entering new AgentExecutor chain...
Thought: Do I need to use a tool? Yes
Action: Current Search
Action Input: Who won the World Cup in 1978
Observation: Argentina national football team
Thought: Do I need to use a tool? No
AI: The last letter in your name is "b" and the winner of the 1978 World Cup was the Argentina national football team.
> Finished chain.


> Finished chain.
'The last letter in your name is "b" and the winner of the 1978 World Cup was the Argentina national football team.'
agent_chain.run(input="whats the current temperature in pomfret?")
> Entering new AgentExecutor chain...
Thought: Do I need to use a tool? Yes
Action: Current Search
Action Input: Current temperature in Pomfret
Observation: Partly cloudy skies. High around 70F. Winds W at 5 to 10 mph. Humidity41%.
Thought: Do I need to use a tool? No
AI: The current temperature in Pomfret is around 70F with partly cloudy skies and winds W at 5 to 10 mph. The humidity is 41%.
> Finished chain.
'The current temperature in Pomfret is around 70F with partly cloudy skies and winds W at 5 to 10 mph. The humidity is 41%.'
previous
Conversation Agent (for Chat Models)
next
MRKL
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
Conversation Agent (for Chat Models)
Conversation Agent (for Chat Models)#
This notebook walks through using an agent optimized for conversation, using ChatModels. Other agents are often optimized for using tools to figure out the best response, which is not ideal in a conversational setting where you may want the agent to be able to chat with the user as well.
This is accomplished with a specific type of agent (chat-conversational-react-description) which expects to be used with a memory component.
!pip install langchain
!pip install google-search-results
!pip install openai
from langchain.agents import Tool
from langchain.memory import ConversationBufferMemory
from langchain.chat_models import ChatOpenAI
from langchain.utilities import SerpAPIWrapper
from langchain.agents import initialize_agent
from langchain.agents import AgentType
from getpass import getpass
SERPAPI_API_KEY = getpass()
search = SerpAPIWrapper(serpapi_api_key=SERPAPI_API_KEY)
tools = [
    Tool(
        name = "Current Search",
        func=search.run,
        description="useful for when you need to answer questions about current events or the current state of the world. the input to this should be a single search term."
    ),
]
memory = ConversationBufferMemory(memory_key="chat_history", return_messages=True)
OPENAI_API_KEY = getpass()
llm=ChatOpenAI(openai_api_key=OPENAI_API_KEY, temperature=0)
agent_chain = initialize_agent(tools, llm, agent=AgentType.CHAT_CONVERSATIONAL_REACT_DESCRIPTION, verbose=True, memory=memory)
agent_chain.run(input="hi, i am bob")
> Entering new AgentExecutor chain...
{
    "action": "Final Answer",


> Entering new AgentExecutor chain...
{
    "action": "Final Answer",
    "action_input": "Hello Bob! How can I assist you today?"
}
> Finished chain.
'Hello Bob! How can I assist you today?'
agent_chain.run(input="what's my name?")
> Entering new AgentExecutor chain...
{
    "action": "Final Answer",
    "action_input": "Your name is Bob."
}
> Finished chain.
'Your name is Bob.'
agent_chain.run("what are some good dinners to make this week, if i like thai food?")
> Entering new AgentExecutor chain...
{
    "action": "Current Search",
    "action_input": "Thai food dinner recipes"
}
Observation: 64 easy Thai recipes for any night of the week · Thai curry noodle soup · Thai yellow cauliflower, snake bean and tofu curry · Thai-spiced chicken hand pies · Thai ...
Thought:{
    "action": "Final Answer",
    "action_input": "Here are some Thai food dinner recipes you can try this week: Thai curry noodle soup, Thai yellow cauliflower, snake bean and tofu curry, Thai-spiced chicken hand pies, and many more. You can find the full list of recipes at the source I found earlier."
}
> Finished chain.
'Here are some Thai food dinner recipes you can try this week: Thai curry noodle soup, Thai yellow cauliflower, snake bean and tofu curry, Thai-spiced chicken hand pies, and many more. You can find the full list of recipes at the source I found earlier.'
agent_chain.run(input="tell me the last letter in my name, and also tell me who won the world cup in 1978?")
> Entering new AgentExecutor chain...
{
    "action": "Final Answer",


> Entering new AgentExecutor chain...
{
    "action": "Final Answer",
    "action_input": "The last letter in your name is 'b'. Argentina won the World Cup in 1978."
}
> Finished chain.
"The last letter in your name is 'b'. Argentina won the World Cup in 1978."
agent_chain.run(input="whats the weather like in pomfret?")
> Entering new AgentExecutor chain...
{
    "action": "Current Search",
    "action_input": "weather in pomfret"
}
Observation: Cloudy with showers. Low around 55F. Winds S at 5 to 10 mph. Chance of rain 60%. Humidity76%.
Thought:{
    "action": "Final Answer",
    "action_input": "Cloudy with showers. Low around 55F. Winds S at 5 to 10 mph. Chance of rain 60%. Humidity76%."
}
> Finished chain.
'Cloudy with showers. Low around 55F. Winds S at 5 to 10 mph. Chance of rain 60%. Humidity76%.'
previous
Custom Agent with Tool Retrieval
next
Conversation Agent
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
ReAct
ReAct#
This notebook showcases using an agent to implement the ReAct logic.
from langchain import OpenAI, Wikipedia
from langchain.agents import initialize_agent, Tool
from langchain.agents import AgentType
from langchain.agents.react.base import DocstoreExplorer
docstore=DocstoreExplorer(Wikipedia())
tools = [
    Tool(
        name="Search",
        func=docstore.search,
        description="useful for when you need to ask with search"
    ),
    Tool(
        name="Lookup",
        func=docstore.lookup,
        description="useful for when you need to ask with lookup"
    )
]
llm = OpenAI(temperature=0, model_name="text-davinci-002")
react = initialize_agent(tools, llm, agent=AgentType.REACT_DOCSTORE, verbose=True)
question = "Author David Chanoff has collaborated with a U.S. Navy admiral who served as the ambassador to the United Kingdom under which President?"
react.run(question)
> Entering new AgentExecutor chain...
Thought: I need to search David Chanoff and find the U.S. Navy admiral he collaborated with. Then I need to find which President the admiral served under.
Action: Search[David Chanoff]


Action: Search[David Chanoff]
Observation: David Chanoff is a noted author of non-fiction work. His work has typically involved collaborations with the principal protagonist of the work concerned. His collaborators have included; Augustus A. White, Joycelyn Elders, Đoàn Văn Toại, William J. Crowe, Ariel Sharon, Kenneth Good and Felix Zandman. He has also written about a wide range of subjects including literary history, education and foreign for The Washington Post, The New Republic and The New York Times Magazine. He has published more than twelve books.
Thought: The U.S. Navy admiral David Chanoff collaborated with is William J. Crowe. I need to find which President he served under.
Action: Search[William J. Crowe]
Observation: William James Crowe Jr. (January 2, 1925 – October 18, 2007) was a United States Navy admiral and diplomat who served as the 11th chairman of the Joint Chiefs of Staff under Presidents Ronald Reagan and George H. W. Bush, and as the ambassador to the United Kingdom and Chair of the Intelligence Oversight Board under President Bill Clinton.
Thought: William J. Crowe served as the ambassador to the United Kingdom under President Bill Clinton, so the answer is Bill Clinton.
Action: Finish[Bill Clinton]
> Finished chain.
'Bill Clinton'
previous
OpenAI Functions Agent
next
Self Ask With Search
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
Multi-Input Tools
 Contents
Multi-Input Tools with a string format
Multi-Input Tools#
This notebook shows how to use a tool that requires multiple inputs with an agent. The recommended way to do so is with the StructuredTool class.
import os
os.environ["LANGCHAIN_TRACING"] = "true"
from langchain import OpenAI
from langchain.agents import initialize_agent, AgentType
llm = OpenAI(temperature=0)
from langchain.tools import StructuredTool
def multiplier(a: float, b: float) -> float:
    """Multiply the provided floats."""
    return a * b
tool = StructuredTool.from_function(multiplier)
# Structured tools are compatible with the STRUCTURED_CHAT_ZERO_SHOT_REACT_DESCRIPTION agent type.
agent_executor = initialize_agent([tool], llm, agent=AgentType.STRUCTURED_CHAT_ZERO_SHOT_REACT_DESCRIPTION, verbose=True)
agent_executor.run("What is 3 times 4")
> Entering new AgentExecutor chain...
Thought: I need to multiply 3 and 4
Action:
```
{
  "action": "multiplier",
  "action_input": {"a": 3, "b": 4}
}
```
Observation: 12
Thought: I know what to respond
Action:
```
{
  "action": "Final Answer",
  "action_input": "3 times 4 is 12"
}
```
> Finished chain.
'3 times 4 is 12'
Multi-Input Tools with a string format#


'3 times 4 is 12'
Multi-Input Tools with a string format#
An alternative to the structured tool would be to use the regular Tool class and accept a single string. The tool would then have to handle the parsing logic to extract the relavent values from the text, which tightly couples the tool representation to the agent prompt. This is still useful if the underlying language model can’t reliabl generate structured schema.
Let’s take the multiplication function as an example. In order to use this, we will tell the agent to generate the “Action Input” as a comma-separated list of length two. We will then write a thin wrapper that takes a string, splits it into two around a comma, and passes both parsed sides as integers to the multiplication function.
from langchain.llms import OpenAI
from langchain.agents import initialize_agent, Tool
from langchain.agents import AgentType
Here is the multiplication function, as well as a wrapper to parse a string as input.
def multiplier(a, b):
    return a * b
def parsing_multiplier(string):
    a, b = string.split(",")
    return multiplier(int(a), int(b))
llm = OpenAI(temperature=0)
tools = [
    Tool(
        name = "Multiplier",
        func=parsing_multiplier,
        description="useful for when you need to multiply two numbers together. The input to this tool should be a comma separated list of numbers of length two, representing the two numbers you want to multiply together. For example, `1,2` would be the input if you wanted to multiply 1 by 2."
    )
]
mrkl = initialize_agent(tools, llm, agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION, verbose=True)
mrkl.run("What is 3 times 4")
> Entering new AgentExecutor chain...


> Entering new AgentExecutor chain...
 I need to multiply two numbers
Action: Multiplier
Action Input: 3,4
Observation: 12
Thought: I now know the final answer
Final Answer: 3 times 4 is 12
> Finished chain.
'3 times 4 is 12'
previous
Defining Custom Tools
next
Tool Input Schema
 Contents

Multi-Input Tools with a string format
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
Tool Input Schema
Tool Input Schema#
By default, tools infer the argument schema by inspecting the function signature. For more strict requirements, custom input schema can be specified, along with custom validation logic.
from typing import Any, Dict
from langchain.agents import AgentType, initialize_agent
from langchain.llms import OpenAI
from langchain.tools.requests.tool import RequestsGetTool, TextRequestsWrapper
from pydantic import BaseModel, Field, root_validator
llm = OpenAI(temperature=0)
!pip install tldextract > /dev/null
[notice] A new release of pip is available: 23.0.1 -> 23.1
[notice] To update, run: pip install --upgrade pip
import tldextract
_APPROVED_DOMAINS = {
    "langchain",
    "wikipedia",
}
class ToolInputSchema(BaseModel):
    url: str = Field(...)

    @root_validator
    def validate_query(cls, values: Dict[str, Any]) -> Dict:
        url = values["url"]
        domain = tldextract.extract(url).domain
        if domain not in _APPROVED_DOMAINS:
            raise ValueError(f"Domain {domain} is not on the approved list:"
                             f" {sorted(_APPROVED_DOMAINS)}")
        return values

tool = RequestsGetTool(args_schema=ToolInputSchema, requests_wrapper=TextRequestsWrapper())
agent = initialize_agent([tool], llm, agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION, verbose=False)
# This will succeed, since there aren't any arguments that will be triggered during validation
answer = agent.run("What's the main title on langchain.com?")
print(answer)


print(answer)
The main title of langchain.com is "LANG CHAIN 🦜🔗 Official Home Page"
agent.run("What's the main title on google.com?")
---------------------------------------------------------------------------
ValidationError                           Traceback (most recent call last)
Cell In[7], line 1
----> 1 agent.run("What's the main title on google.com?")
File ~/code/lc/lckg/langchain/chains/base.py:213, in Chain.run(self, *args, **kwargs)
    211     if len(args) != 1:
    212         raise ValueError("`run` supports only one positional argument.")
--> 213     return self(args[0])[self.output_keys[0]]
    215 if kwargs and not args:
    216     return self(kwargs)[self.output_keys[0]]
File ~/code/lc/lckg/langchain/chains/base.py:116, in Chain.__call__(self, inputs, return_only_outputs)
    114 except (KeyboardInterrupt, Exception) as e:
    115     self.callback_manager.on_chain_error(e, verbose=self.verbose)
--> 116     raise e
    117 self.callback_manager.on_chain_end(outputs, verbose=self.verbose)
    118 return self.prep_outputs(inputs, outputs, return_only_outputs)
File ~/code/lc/lckg/langchain/chains/base.py:113, in Chain.__call__(self, inputs, return_only_outputs)
    107 self.callback_manager.on_chain_start(
    108     {"name": self.__class__.__name__},
    109     inputs,
    110     verbose=self.verbose,
    111 )
    112 try:
--> 113     outputs = self._call(inputs)
    114 except (KeyboardInterrupt, Exception) as e:


114 except (KeyboardInterrupt, Exception) as e:
    115     self.callback_manager.on_chain_error(e, verbose=self.verbose)
File ~/code/lc/lckg/langchain/agents/agent.py:792, in AgentExecutor._call(self, inputs)
    790 # We now enter the agent loop (until it returns something).
    791 while self._should_continue(iterations, time_elapsed):
--> 792     next_step_output = self._take_next_step(
    793         name_to_tool_map, color_mapping, inputs, intermediate_steps
    794     )
    795     if isinstance(next_step_output, AgentFinish):
    796         return self._return(next_step_output, intermediate_steps)
File ~/code/lc/lckg/langchain/agents/agent.py:695, in AgentExecutor._take_next_step(self, name_to_tool_map, color_mapping, inputs, intermediate_steps)
    693         tool_run_kwargs["llm_prefix"] = ""
    694     # We then call the tool on the tool input to get an observation
--> 695     observation = tool.run(
    696         agent_action.tool_input,
    697         verbose=self.verbose,
    698         color=color,
    699         **tool_run_kwargs,
    700     )
    701 else:
    702     tool_run_kwargs = self.agent.tool_run_logging_kwargs()
File ~/code/lc/lckg/langchain/tools/base.py:110, in BaseTool.run(self, tool_input, verbose, start_color, color, **kwargs)
    101 def run(
    102     self,
    103     tool_input: Union[str, Dict],
   (...)
    107     **kwargs: Any,
    108 ) -> str:


107     **kwargs: Any,
    108 ) -> str:
    109     """Run the tool."""
--> 110     run_input = self._parse_input(tool_input)
    111     if not self.verbose and verbose is not None:
    112         verbose_ = verbose
File ~/code/lc/lckg/langchain/tools/base.py:71, in BaseTool._parse_input(self, tool_input)
     69 if issubclass(input_args, BaseModel):
     70     key_ = next(iter(input_args.__fields__.keys()))
---> 71     input_args.parse_obj({key_: tool_input})
     72 # Passing as a positional argument is more straightforward for
     73 # backwards compatability
     74 return tool_input
File ~/code/lc/lckg/.venv/lib/python3.11/site-packages/pydantic/main.py:526, in pydantic.main.BaseModel.parse_obj()
File ~/code/lc/lckg/.venv/lib/python3.11/site-packages/pydantic/main.py:341, in pydantic.main.BaseModel.__init__()
ValidationError: 1 validation error for ToolInputSchema
__root__
  Domain google is not on the approved list: ['langchain', 'wikipedia'] (type=value_error)
previous
Multi-Input Tools
next
Human-in-the-loop Tool Validation
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
Human-in-the-loop Tool Validation
 Contents
Adding Human Approval
Configuring Human Approval
Human-in-the-loop Tool Validation#
This walkthrough demonstrates how to add Human validation to any Tool. We’ll do this using the HumanApprovalCallbackhandler.
Let’s suppose we need to make use of the ShellTool. Adding this tool to an automated flow poses obvious risks. Let’s see how we could enforce manual human approval of inputs going into this tool.
Note: We generally recommend against using the ShellTool. There’s a lot of ways to misuse it, and it’s not required for most use cases. We employ it here only for demonstration purposes.
from langchain.callbacks import HumanApprovalCallbackHandler
from langchain.tools import ShellTool
tool = ShellTool()
print(tool.run('echo Hello World!'))
Hello World!
Adding Human Approval#
Adding the default HumanApprovalCallbackHandler to the tool will make it so that a user has to manually approve every input to the tool before the command is actually executed.
tool = ShellTool(callbacks=[HumanApprovalCallbackHandler()])
print(tool.run("ls /usr"))
Do you approve of the following input? Anything except 'Y'/'Yes' (case-insensitive) will be treated as a no.
ls /usr
yes
X11
X11R6
bin
lib
libexec
local
sbin
share
standalone
print(tool.run("ls /private"))
Do you approve of the following input? Anything except 'Y'/'Yes' (case-insensitive) will be treated as a no.
ls /private
no
---------------------------------------------------------------------------
HumanRejectedException                    Traceback (most recent call last)
Cell In[17], line 1
----> 1 print(tool.run("ls /private"))


----> 1 print(tool.run("ls /private"))
File ~/langchain/langchain/tools/base.py:257, in BaseTool.run(self, tool_input, verbose, start_color, color, callbacks, **kwargs)
    255 # TODO: maybe also pass through run_manager is _run supports kwargs
    256 new_arg_supported = signature(self._run).parameters.get("run_manager")
--> 257 run_manager = callback_manager.on_tool_start(
    258     {"name": self.name, "description": self.description},
    259     tool_input if isinstance(tool_input, str) else str(tool_input),
    260     color=start_color,
    261     **kwargs,
    262 )
    263 try:
    264     tool_args, tool_kwargs = self._to_args_and_kwargs(parsed_input)
File ~/langchain/langchain/callbacks/manager.py:672, in CallbackManager.on_tool_start(self, serialized, input_str, run_id, parent_run_id, **kwargs)
    669 if run_id is None:
    670     run_id = uuid4()
--> 672 _handle_event(
    673     self.handlers,
    674     "on_tool_start",
    675     "ignore_agent",
    676     serialized,
    677     input_str,
    678     run_id=run_id,
    679     parent_run_id=self.parent_run_id,
    680     **kwargs,
    681 )
    683 return CallbackManagerForToolRun(
    684     run_id, self.handlers, self.inheritable_handlers, self.parent_run_id
    685 )
File ~/langchain/langchain/callbacks/manager.py:157, in _handle_event(handlers, event_name, ignore_condition_name, *args, **kwargs)


155 except Exception as e:
    156     if handler.raise_error:
--> 157         raise e
    158     logging.warning(f"Error in {event_name} callback: {e}")
File ~/langchain/langchain/callbacks/manager.py:139, in _handle_event(handlers, event_name, ignore_condition_name, *args, **kwargs)
    135 try:
    136     if ignore_condition_name is None or not getattr(
    137         handler, ignore_condition_name
    138     ):
--> 139         getattr(handler, event_name)(*args, **kwargs)
    140 except NotImplementedError as e:
    141     if event_name == "on_chat_model_start":
File ~/langchain/langchain/callbacks/human.py:48, in HumanApprovalCallbackHandler.on_tool_start(self, serialized, input_str, run_id, parent_run_id, **kwargs)
     38 def on_tool_start(
     39     self,
     40     serialized: Dict[str, Any],
   (...)
     45     **kwargs: Any,
     46 ) -> Any:
     47     if self._should_check(serialized) and not self._approve(input_str):
---> 48         raise HumanRejectedException(
     49             f"Inputs {input_str} to tool {serialized} were rejected."
     50         )
HumanRejectedException: Inputs ls /private to tool {'name': 'terminal', 'description': 'Run shell commands on this MacOS machine.'} were rejected.
Configuring Human Approval#
Let’s suppose we have an agent that takes in multiple tools, and we want it to only trigger human approval requests on certain tools and certain inputs. We can configure out callback handler to do just this.
from langchain.agents import load_tools


from langchain.agents import load_tools
from langchain.agents import initialize_agent
from langchain.agents import AgentType
from langchain.llms import OpenAI
def _should_check(serialized_obj: dict) -> bool:
    # Only require approval on ShellTool.
    return serialized_obj.get("name") == "terminal"
def _approve(_input: str) -> bool:
    if _input == "echo 'Hello World'":
        return True
    msg = (
        "Do you approve of the following input? "
        "Anything except 'Y'/'Yes' (case-insensitive) will be treated as a no."
    )
    msg += "\n\n" + _input + "\n"
    resp = input(msg)
    return resp.lower() in ("yes", "y")
callbacks = [HumanApprovalCallbackHandler(should_check=_should_check, approve=_approve)]
llm = OpenAI(temperature=0)
tools = load_tools(["wikipedia", "llm-math", "terminal"], llm=llm)
agent = initialize_agent(
    tools,
    llm,
    agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION,
)
agent.run("It's 2023 now. How many years ago did Konrad Adenauer become Chancellor of Germany.", callbacks=callbacks)
'Konrad Adenauer became Chancellor of Germany in 1949, 74 years ago.'
agent.run("print 'Hello World' in the terminal", callbacks=callbacks)
'Hello World'
agent.run("list all directories in /private", callbacks=callbacks)
Do you approve of the following input? Anything except 'Y'/'Yes' (case-insensitive) will be treated as a no.
ls /private
no
---------------------------------------------------------------------------


ls /private
no
---------------------------------------------------------------------------
HumanRejectedException                    Traceback (most recent call last)
Cell In[39], line 1
----> 1 agent.run("list all directories in /private", callbacks=callbacks)
File ~/langchain/langchain/chains/base.py:236, in Chain.run(self, callbacks, *args, **kwargs)
    234     if len(args) != 1:
    235         raise ValueError("`run` supports only one positional argument.")
--> 236     return self(args[0], callbacks=callbacks)[self.output_keys[0]]
    238 if kwargs and not args:
    239     return self(kwargs, callbacks=callbacks)[self.output_keys[0]]
File ~/langchain/langchain/chains/base.py:140, in Chain.__call__(self, inputs, return_only_outputs, callbacks)
    138 except (KeyboardInterrupt, Exception) as e:
    139     run_manager.on_chain_error(e)
--> 140     raise e
    141 run_manager.on_chain_end(outputs)
    142 return self.prep_outputs(inputs, outputs, return_only_outputs)
File ~/langchain/langchain/chains/base.py:134, in Chain.__call__(self, inputs, return_only_outputs, callbacks)
    128 run_manager = callback_manager.on_chain_start(
    129     {"name": self.__class__.__name__},
    130     inputs,
    131 )
    132 try:
    133     outputs = (
--> 134         self._call(inputs, run_manager=run_manager)
    135         if new_arg_supported
    136         else self._call(inputs)
    137     )
    138 except (KeyboardInterrupt, Exception) as e:
    139     run_manager.on_chain_error(e)


139     run_manager.on_chain_error(e)
File ~/langchain/langchain/agents/agent.py:953, in AgentExecutor._call(self, inputs, run_manager)
    951 # We now enter the agent loop (until it returns something).
    952 while self._should_continue(iterations, time_elapsed):
--> 953     next_step_output = self._take_next_step(
    954         name_to_tool_map,
    955         color_mapping,
    956         inputs,
    957         intermediate_steps,
    958         run_manager=run_manager,
    959     )
    960     if isinstance(next_step_output, AgentFinish):
    961         return self._return(
    962             next_step_output, intermediate_steps, run_manager=run_manager
    963         )
File ~/langchain/langchain/agents/agent.py:820, in AgentExecutor._take_next_step(self, name_to_tool_map, color_mapping, inputs, intermediate_steps, run_manager)
    818         tool_run_kwargs["llm_prefix"] = ""
    819     # We then call the tool on the tool input to get an observation
--> 820     observation = tool.run(
    821         agent_action.tool_input,
    822         verbose=self.verbose,
    823         color=color,
    824         callbacks=run_manager.get_child() if run_manager else None,
    825         **tool_run_kwargs,
    826     )
    827 else:
    828     tool_run_kwargs = self.agent.tool_run_logging_kwargs()
File ~/langchain/langchain/tools/base.py:257, in BaseTool.run(self, tool_input, verbose, start_color, color, callbacks, **kwargs)


255 # TODO: maybe also pass through run_manager is _run supports kwargs
    256 new_arg_supported = signature(self._run).parameters.get("run_manager")
--> 257 run_manager = callback_manager.on_tool_start(
    258     {"name": self.name, "description": self.description},
    259     tool_input if isinstance(tool_input, str) else str(tool_input),
    260     color=start_color,
    261     **kwargs,
    262 )
    263 try:
    264     tool_args, tool_kwargs = self._to_args_and_kwargs(parsed_input)
File ~/langchain/langchain/callbacks/manager.py:672, in CallbackManager.on_tool_start(self, serialized, input_str, run_id, parent_run_id, **kwargs)
    669 if run_id is None:
    670     run_id = uuid4()
--> 672 _handle_event(
    673     self.handlers,
    674     "on_tool_start",
    675     "ignore_agent",
    676     serialized,
    677     input_str,
    678     run_id=run_id,
    679     parent_run_id=self.parent_run_id,
    680     **kwargs,
    681 )
    683 return CallbackManagerForToolRun(
    684     run_id, self.handlers, self.inheritable_handlers, self.parent_run_id
    685 )
File ~/langchain/langchain/callbacks/manager.py:157, in _handle_event(handlers, event_name, ignore_condition_name, *args, **kwargs)
    155 except Exception as e:
    156     if handler.raise_error:
--> 157         raise e
    158     logging.warning(f"Error in {event_name} callback: {e}")


158     logging.warning(f"Error in {event_name} callback: {e}")
File ~/langchain/langchain/callbacks/manager.py:139, in _handle_event(handlers, event_name, ignore_condition_name, *args, **kwargs)
    135 try:
    136     if ignore_condition_name is None or not getattr(
    137         handler, ignore_condition_name
    138     ):
--> 139         getattr(handler, event_name)(*args, **kwargs)
    140 except NotImplementedError as e:
    141     if event_name == "on_chat_model_start":
File ~/langchain/langchain/callbacks/human.py:48, in HumanApprovalCallbackHandler.on_tool_start(self, serialized, input_str, run_id, parent_run_id, **kwargs)
     38 def on_tool_start(
     39     self,
     40     serialized: Dict[str, Any],
   (...)
     45     **kwargs: Any,
     46 ) -> Any:
     47     if self._should_check(serialized) and not self._approve(input_str):
---> 48         raise HumanRejectedException(
     49             f"Inputs {input_str} to tool {serialized} were rejected."
     50         )
HumanRejectedException: Inputs ls /private to tool {'name': 'terminal', 'description': 'Run shell commands on this MacOS machine.'} were rejected.
previous
Tool Input Schema
next
Tools as OpenAI Functions
 Contents

Adding Human Approval
Configuring Human Approval
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
Defining Custom Tools
 Contents
Completely New Tools - String Input and Output
Tool dataclass
Subclassing the BaseTool class
Using the tool decorator
Custom Structured Tools
StructuredTool dataclass
Subclassing the BaseTool
Using the decorator
Modify existing tools
Defining the priorities among Tools
Using tools to return directly
Handling Tool Errors
Defining Custom Tools#
When constructing your own agent, you will need to provide it with a list of Tools that it can use. Besides the actual function that is called, the Tool consists of several components:
name (str), is required and must be unique within a set of tools provided to an agent
description (str), is optional but recommended, as it is used by an agent to determine tool use
return_direct (bool), defaults to False
args_schema (Pydantic BaseModel), is optional but recommended, can be used to provide more information (e.g., few-shot examples) or validation for expected parameters.
There are two main ways to define a tool, we will cover both in the example below.
# Import things that are needed generically
from langchain import LLMMathChain, SerpAPIWrapper
from langchain.agents import AgentType, initialize_agent
from langchain.chat_models import ChatOpenAI
from langchain.tools import BaseTool, StructuredTool, Tool, tool
Initialize the LLM to use for the agent.
llm = ChatOpenAI(temperature=0)
Completely New Tools - String Input and Output#
The simplest tools accept a single query string and return a string output. If your tool function requires multiple arguments, you might want to skip down to the StructuredTool section below.
There are two ways to do this: either by using the Tool dataclass, or by subclassing the BaseTool class.
Tool dataclass#


Tool dataclass#
The ‘Tool’ dataclass wraps functions that accept a single string input and returns a string output.
# Load the tool configs that are needed.
search = SerpAPIWrapper()
llm_math_chain = LLMMathChain(llm=llm, verbose=True)
tools = [
    Tool.from_function(
        func=search.run,
        name = "Search",
        description="useful for when you need to answer questions about current events"
        # coroutine= ... <- you can specify an async method if desired as well
    ),
]
/Users/wfh/code/lc/lckg/langchain/chains/llm_math/base.py:50: UserWarning: Directly instantiating an LLMMathChain with an llm is deprecated. Please instantiate with llm_chain argument or using the from_llm class method.
  warnings.warn(
You can also define a custom `args_schema`` to provide more information about inputs.
from pydantic import BaseModel, Field
class CalculatorInput(BaseModel):
    question: str = Field()

tools.append(
    Tool.from_function(
        func=llm_math_chain.run,
        name="Calculator",
        description="useful for when you need to answer questions about math",
        args_schema=CalculatorInput
        # coroutine= ... <- you can specify an async method if desired as well
    )
)
# Construct the agent. We will use the default agent type here.
# See documentation for a full list of options.
agent = initialize_agent(tools, llm, agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION, verbose=True)
agent.run("Who is Leo DiCaprio's girlfriend? What is her current age raised to the 0.43 power?")
> Entering new AgentExecutor chain...


> Entering new AgentExecutor chain...
I need to find out Leo DiCaprio's girlfriend's name and her age
Action: Search
Action Input: "Leo DiCaprio girlfriend"
Observation: After rumours of a romance with Gigi Hadid, the Oscar winner has seemingly moved on. First being linked to the television personality in September 2022, it appears as if his "age bracket" has moved up. This follows his rumoured relationship with mere 19-year-old Eden Polani.
Thought:I still need to find out his current girlfriend's name and age
Action: Search
Action Input: "Leo DiCaprio current girlfriend"
Observation: Just Jared on Instagram: “Leonardo DiCaprio & girlfriend Camila Morrone couple up for a lunch date!
Thought:Now that I know his girlfriend's name is Camila Morrone, I need to find her current age
Action: Search
Action Input: "Camila Morrone age"
Observation: 25 years
Thought:Now that I have her age, I need to calculate her age raised to the 0.43 power
Action: Calculator
Action Input: 25^(0.43)
> Entering new LLMMathChain chain...
25^(0.43)```text
25**(0.43)
```
...numexpr.evaluate("25**(0.43)")...
Answer: 3.991298452658078
> Finished chain.
Observation: Answer: 3.991298452658078
Thought:I now know the final answer
Final Answer: Camila Morrone's current age raised to the 0.43 power is approximately 3.99.
> Finished chain.
"Camila Morrone's current age raised to the 0.43 power is approximately 3.99."
Subclassing the BaseTool class#


Subclassing the BaseTool class#
You can also directly subclass BaseTool. This is useful if you want more control over the instance variables or if you want to propagate callbacks to nested chains or other tools.
from typing import Optional, Type
from langchain.callbacks.manager import AsyncCallbackManagerForToolRun, CallbackManagerForToolRun
class CustomSearchTool(BaseTool):
    name = "custom_search"
    description = "useful for when you need to answer questions about current events"
    def _run(self, query: str, run_manager: Optional[CallbackManagerForToolRun] = None) -> str:
        """Use the tool."""
        return search.run(query)

    async def _arun(self, query: str, run_manager: Optional[AsyncCallbackManagerForToolRun] = None) -> str:
        """Use the tool asynchronously."""
        raise NotImplementedError("custom_search does not support async")

class CustomCalculatorTool(BaseTool):
    name = "Calculator"
    description = "useful for when you need to answer questions about math"
    args_schema: Type[BaseModel] = CalculatorInput
    def _run(self, query: str, run_manager: Optional[CallbackManagerForToolRun] = None) -> str:
        """Use the tool."""
        return llm_math_chain.run(query)

    async def _arun(self, query: str,  run_manager: Optional[AsyncCallbackManagerForToolRun] = None) -> str:
        """Use the tool asynchronously."""
        raise NotImplementedError("Calculator does not support async")
tools = [CustomSearchTool(), CustomCalculatorTool()]
agent = initialize_agent(tools, llm, agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION, verbose=True)


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 use custom_search to find out who Leo DiCaprio's girlfriend is, and then use the Calculator to raise her age to the 0.43 power.
Action: custom_search
Action Input: "Leo DiCaprio girlfriend"
Observation: After rumours of a romance with Gigi Hadid, the Oscar winner has seemingly moved on. First being linked to the television personality in September 2022, it appears as if his "age bracket" has moved up. This follows his rumoured relationship with mere 19-year-old Eden Polani.
Thought:I need to find out the current age of Eden Polani.
Action: custom_search
Action Input: "Eden Polani age"
Observation: 19 years old
Thought:Now I can use the Calculator to raise her age to the 0.43 power.
Action: Calculator
Action Input: 19 ^ 0.43
> Entering new LLMMathChain chain...
19 ^ 0.43```text
19 ** 0.43
```
...numexpr.evaluate("19 ** 0.43")...
Answer: 3.547023357958959
> Finished chain.
Observation: Answer: 3.547023357958959
Thought:I now know the final answer.
Final Answer: 3.547023357958959
> Finished chain.
'3.547023357958959'
Using the tool decorator#


'3.547023357958959'
Using the tool decorator#
To make it easier to define custom tools, a @tool decorator is provided. This decorator can be used to quickly create a Tool from a simple function. The decorator uses the function name as the tool name by default, but this can be overridden by passing a string as the first argument. Additionally, the decorator will use the function’s docstring as the tool’s description.
from langchain.tools import tool
@tool
def search_api(query: str) -> str:
    """Searches the API for the query."""
    return f"Results for query {query}"
search_api
You can also provide arguments like the tool name and whether to return directly.
@tool("search", return_direct=True)
def search_api(query: str) -> str:
    """Searches the API for the query."""
    return "Results"
search_api
Tool(name='search', description='search(query: str) -> str - Searches the API for the query.', args_schema=<class 'pydantic.main.SearchApi'>, return_direct=True, verbose=False, callback_manager=<langchain.callbacks.shared.SharedCallbackManager object at 0x12748c4c0>, func=<function search_api at 0x16bd66310>, coroutine=None)
You can also provide args_schema to provide more information about the argument
class SearchInput(BaseModel):
    query: str = Field(description="should be a search query")

@tool("search", return_direct=True, args_schema=SearchInput)
def search_api(query: str) -> str:
    """Searches the API for the query."""
    return "Results"
search_api


"""Searches the API for the query."""
    return "Results"
search_api
Tool(name='search', description='search(query: str) -> str - Searches the API for the query.', args_schema=<class '__main__.SearchInput'>, return_direct=True, verbose=False, callback_manager=<langchain.callbacks.shared.SharedCallbackManager object at 0x12748c4c0>, func=<function search_api at 0x16bcf0ee0>, coroutine=None)
Custom Structured Tools#
If your functions require more structured arguments, you can use the StructuredTool class directly, or still subclass the BaseTool class.
StructuredTool dataclass#
To dynamically generate a structured tool from a given function, the fastest way to get started is with StructuredTool.from_function().
import requests
from langchain.tools import StructuredTool
def post_message(url: str, body: dict, parameters: Optional[dict] = None) -> str:
    """Sends a POST request to the given url with the given body and parameters."""
    result = requests.post(url, json=body, params=parameters)
    return f"Status: {result.status_code} - {result.text}"
tool = StructuredTool.from_function(post_message)
Subclassing the BaseTool#
The BaseTool automatically infers the schema from the _run method’s signature.
from typing import Optional, Type
from langchain.callbacks.manager import AsyncCallbackManagerForToolRun, CallbackManagerForToolRun

class CustomSearchTool(BaseTool):
    name = "custom_search"
    description = "useful for when you need to answer questions about current events"


description = "useful for when you need to answer questions about current events"
    def _run(self, query: str, engine: str = "google", gl: str = "us", hl: str = "en", run_manager: Optional[CallbackManagerForToolRun] = None) -> str:
        """Use the tool."""
        search_wrapper = SerpAPIWrapper(params={"engine": engine, "gl": gl, "hl": hl})
        return search_wrapper.run(query)

    async def _arun(self, query: str,  engine: str = "google", gl: str = "us", hl: str = "en", run_manager: Optional[AsyncCallbackManagerForToolRun] = None) -> str:
        """Use the tool asynchronously."""
        raise NotImplementedError("custom_search does not support async")
# You can provide a custom args schema to add descriptions or custom validation
class SearchSchema(BaseModel):
    query: str = Field(description="should be a search query")
    engine: str = Field(description="should be a search engine")
    gl: str = Field(description="should be a country code")
    hl: str = Field(description="should be a language code")
class CustomSearchTool(BaseTool):
    name = "custom_search"
    description = "useful for when you need to answer questions about current events"
    args_schema: Type[SearchSchema] = SearchSchema
    def _run(self, query: str, engine: str = "google", gl: str = "us", hl: str = "en", run_manager: Optional[CallbackManagerForToolRun] = None) -> str:
        """Use the tool."""
        search_wrapper = SerpAPIWrapper(params={"engine": engine, "gl": gl, "hl": hl})
        return search_wrapper.run(query)


return search_wrapper.run(query)

    async def _arun(self, query: str,  engine: str = "google", gl: str = "us", hl: str = "en", run_manager: Optional[AsyncCallbackManagerForToolRun] = None) -> str:
        """Use the tool asynchronously."""
        raise NotImplementedError("custom_search does not support async")

Using the decorator#
The tool decorator creates a structured tool automatically if the signature has multiple arguments.
import requests
from langchain.tools import tool
@tool
def post_message(url: str, body: dict, parameters: Optional[dict] = None) -> str:
    """Sends a POST request to the given url with the given body and parameters."""
    result = requests.post(url, json=body, params=parameters)
    return f"Status: {result.status_code} - {result.text}"
Modify existing tools#
Now, we show how to load existing tools and modify them directly. In the example below, we do something really simple and change the Search tool to have the name Google Search.
from langchain.agents import load_tools
tools = load_tools(["serpapi", "llm-math"], llm=llm)
tools[0].name = "Google Search"
agent = initialize_agent(tools, llm, agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION, verbose=True)
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 Leo DiCaprio's girlfriend's name and her age.
Action: Google Search
Action Input: "Leo DiCaprio girlfriend"


Action: Google Search
Action Input: "Leo DiCaprio girlfriend"
Observation: After rumours of a romance with Gigi Hadid, the Oscar winner has seemingly moved on. First being linked to the television personality in September 2022, it appears as if his "age bracket" has moved up. This follows his rumoured relationship with mere 19-year-old Eden Polani.
Thought:I still need to find out his current girlfriend's name and her age.
Action: Google Search
Action Input: "Leo DiCaprio current girlfriend age"
Observation: Leonardo DiCaprio has been linked with 19-year-old model Eden Polani, continuing the rumour that he doesn't date any women over the age of ...
Thought:I need to find out the age of Eden Polani.
Action: Calculator
Action Input: 19^(0.43)
Observation: Answer: 3.547023357958959
Thought:I now know the final answer.
Final Answer: The age of Leo DiCaprio's girlfriend raised to the 0.43 power is approximately 3.55.
> Finished chain.
"The age of Leo DiCaprio's girlfriend raised to the 0.43 power is approximately 3.55."
Defining the priorities among Tools#
When you made a Custom tool, you may want the Agent to use the custom tool more than normal tools.
For example, you made a custom tool, which gets information on music from your database. When a user wants information on songs, You want the Agent to use  the custom tool more than the normal Search tool. But the Agent might prioritize a normal Search tool.
This can be accomplished by adding a statement such as Use this more than the normal search if the question is about Music, like 'who is the singer of yesterday?' or 'what is the most popular song in 2022?' to the description.


An example is below.
# Import things that are needed generically
from langchain.agents import initialize_agent, Tool
from langchain.agents import AgentType
from langchain.llms import OpenAI
from langchain import LLMMathChain, SerpAPIWrapper
search = SerpAPIWrapper()
tools = [
    Tool(
        name = "Search",
        func=search.run,
        description="useful for when you need to answer questions about current events"
    ),
    Tool(
        name="Music Search",
        func=lambda x: "'All I Want For Christmas Is You' by Mariah Carey.", #Mock Function
        description="A Music search engine. Use this more than the normal search if the question is about Music, like 'who is the singer of yesterday?' or 'what is the most popular song in 2022?'",
    )
]
agent = initialize_agent(tools, OpenAI(temperature=0), agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION, verbose=True)
agent.run("what is the most famous song of christmas")
> Entering new AgentExecutor chain...
 I should use a music search engine to find the answer
Action: Music Search
Action Input: most famous song of christmas'All I Want For Christmas Is You' by Mariah Carey. I now know the final answer
Final Answer: 'All I Want For Christmas Is You' by Mariah Carey.
> Finished chain.
"'All I Want For Christmas Is You' by Mariah Carey."
Using tools to return directly#
Often, it can be desirable to have a tool output returned directly to the user, if it’s called. You can do this easily with LangChain by setting the return_direct flag for a tool to be True.
llm_math_chain = LLMMathChain(llm=llm)
tools = [


llm_math_chain = LLMMathChain(llm=llm)
tools = [
    Tool(
        name="Calculator",
        func=llm_math_chain.run,
        description="useful for when you need to answer questions about math",
        return_direct=True
    )
]
llm = OpenAI(temperature=0)
agent = initialize_agent(tools, llm, agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION, verbose=True)
agent.run("whats 2**.12")
> Entering new AgentExecutor chain...
 I need to calculate this
Action: Calculator
Action Input: 2**.12Answer: 1.086734862526058
> Finished chain.
'Answer: 1.086734862526058'
Handling Tool Errors#
When a tool encounters an error and the exception is not caught, the agent will stop executing. If you want the agent to continue execution, you can raise a ToolException and set handle_tool_error accordingly.
When ToolException is thrown, the agent will not stop working, but will handle the exception according to the handle_tool_error variable of the tool, and the processing result will be returned to the agent as observation, and printed in red.
You can set handle_tool_error to True, set it a unified string value, or set it as a function. If it’s set as a function, the function should take a ToolException as a parameter and return a str value.
Please note that only raising a ToolException won’t be effective. You need to first set the handle_tool_error of the tool because its default value is False.
from langchain.schema import ToolException
from langchain import SerpAPIWrapper
from langchain.agents import AgentType, initialize_agent
from langchain.chat_models import ChatOpenAI
from langchain.tools import Tool


from langchain.chat_models import ChatOpenAI
from langchain.tools import Tool
from langchain.chat_models import ChatOpenAI
def _handle_error(error:ToolException) -> str:
    return  "The following errors occurred during tool execution:" + error.args[0]+ "Please try another tool."
def search_tool1(s: str):raise ToolException("The search tool1 is not available.")
def search_tool2(s: str):raise ToolException("The search tool2 is not available.")
search_tool3 = SerpAPIWrapper()
description="useful for when you need to answer questions about current events.You should give priority to using it."
tools = [
    Tool.from_function(
        func=search_tool1,
        name="Search_tool1",
        description=description,
        handle_tool_error=True,
    ),
    Tool.from_function(
        func=search_tool2,
        name="Search_tool2",
        description=description,
        handle_tool_error=_handle_error,
    ),
    Tool.from_function(
        func=search_tool3.run,
        name="Search_tool3",
        description="useful for when you need to answer questions about current events",
    ),
]
agent = initialize_agent(
    tools,
    ChatOpenAI(temperature=0),
    agent=AgentType.ZERO_SHOT_REACT_DESCRIPTION,
    verbose=True,
)
agent.run("Who is Leo DiCaprio's girlfriend?")
> Entering new AgentExecutor chain...
I should use Search_tool1 to find recent news articles about Leo DiCaprio's personal life.
Action: Search_tool1
Action Input: "Leo DiCaprio girlfriend"
Observation: The search tool1 is not available.
Thought:I should try using Search_tool2 instead.
Action: Search_tool2


Thought:I should try using Search_tool2 instead.
Action: Search_tool2
Action Input: "Leo DiCaprio girlfriend"
Observation: The following errors occurred during tool execution:The search tool2 is not available.Please try another tool.
Thought:I should try using Search_tool3 as a last resort.
Action: Search_tool3
Action Input: "Leo DiCaprio girlfriend"
Observation: Leonardo DiCaprio and Gigi Hadid were recently spotted at a pre-Oscars party, sparking interest once again in their rumored romance. The Revenant actor and the model first made headlines when they were spotted together at a New York Fashion Week afterparty in September 2022.
Thought:Based on the information from Search_tool3, it seems that Gigi Hadid is currently rumored to be Leo DiCaprio's girlfriend.
Final Answer: Gigi Hadid is currently rumored to be Leo DiCaprio's girlfriend.
> Finished chain.
"Gigi Hadid is currently rumored to be Leo DiCaprio's girlfriend."
previous
Getting Started
next
Multi-Input Tools
 Contents

Completely New Tools - String Input and Output
Tool dataclass
Subclassing the BaseTool class
Using the tool decorator
Custom Structured Tools
StructuredTool dataclass
Subclassing the BaseTool
Using the decorator
Modify existing tools
Defining the priorities among Tools
Using tools to return directly
Handling Tool Errors
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
Tools as OpenAI Functions
Tools as OpenAI Functions#
This notebook goes over how to use LangChain tools as OpenAI functions.
from langchain.chat_models import ChatOpenAI
from langchain.schema import HumanMessage
model = ChatOpenAI(model="gpt-3.5-turbo-0613")
from langchain.tools import MoveFileTool, format_tool_to_openai_function
tools = [MoveFileTool()]
functions = [format_tool_to_openai_function(t) for t in tools]
message = model.predict_messages([HumanMessage(content='move file foo to bar')], functions=functions)
message
AIMessage(content='', additional_kwargs={'function_call': {'name': 'move_file', 'arguments': '{\n  "source_path": "foo",\n  "destination_path": "bar"\n}'}}, example=False)
message.additional_kwargs['function_call']
{'name': 'move_file',
 'arguments': '{\n  "source_path": "foo",\n  "destination_path": "bar"\n}'}
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Human-in-the-loop Tool Validation
next
Apify
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.md
.pdf
Getting Started
 Contents
List of Tools
Getting Started#
Tools are functions that agents can use to interact with the world.
These tools can be generic utilities (e.g. search), other chains, or even other agents.
Currently, tools can be loaded with the following snippet:
from langchain.agents import load_tools
tool_names = [...]
tools = load_tools(tool_names)
Some tools (e.g. chains, agents) may require a base LLM to use to initialize them.
In that case, you can pass in an LLM as well:
from langchain.agents import load_tools
tool_names = [...]
llm = ...
tools = load_tools(tool_names, llm=llm)
Below is a list of all supported tools and relevant information:
Tool Name: The name the LLM refers to the tool by.
Tool Description: The description of the tool that is passed to the LLM.
Notes: Notes about the tool that are NOT passed to the LLM.
Requires LLM: Whether this tool requires an LLM to be initialized.
(Optional) Extra Parameters: What extra parameters are required to initialize this tool.
List of Tools#
python_repl
Tool Name: Python REPL
Tool Description: A Python shell. Use this to execute python commands. Input should be a valid python command. If you expect output it should be printed out.
Notes: Maintains state.
Requires LLM: No
serpapi
Tool Name: Search
Tool Description: A search engine. Useful for when you need to answer questions about current events. Input should be a search query.
Notes: Calls the Serp API and then parses results.
Requires LLM: No
wolfram-alpha
Tool Name: Wolfram Alpha


Requires LLM: No
wolfram-alpha
Tool Name: Wolfram Alpha
Tool Description: A wolfram alpha search engine. Useful for when you need to answer questions about Math, Science, Technology, Culture, Society and Everyday Life. Input should be a search query.
Notes: Calls the Wolfram Alpha API and then parses results.
Requires LLM: No
Extra Parameters: wolfram_alpha_appid: The Wolfram Alpha app id.
requests
Tool Name: Requests
Tool Description: A portal to the internet. Use this when you need to get specific content from a site. Input should be a specific url, and the output will be all the text on that page.
Notes: Uses the Python requests module.
Requires LLM: No
terminal
Tool Name: Terminal
Tool Description: Executes commands in a terminal. Input should be valid commands, and the output will be any output from running that command.
Notes: Executes commands with subprocess.
Requires LLM: No
pal-math
Tool Name: PAL-MATH
Tool Description: A language model that is excellent at solving complex word math problems. Input should be a fully worded hard word math problem.
Notes: Based on this paper.
Requires LLM: Yes
pal-colored-objects
Tool Name: PAL-COLOR-OBJ
Tool Description: A language model that is wonderful at reasoning about position and the color attributes of objects. Input should be a fully worded hard reasoning problem. Make sure to include all information about the objects AND the final question you want to answer.
Notes: Based on this paper.
Requires LLM: Yes
llm-math
Tool Name: Calculator
Tool Description: Useful for when you need to answer questions about math.
Notes: An instance of the LLMMath chain.
Requires LLM: Yes
open-meteo-api
Tool Name: Open Meteo API


Requires LLM: Yes
open-meteo-api
Tool Name: Open Meteo API
Tool Description: Useful for when you want to get weather information from the OpenMeteo API. The input should be a question in natural language that this API can answer.
Notes: A natural language connection to the Open Meteo API (https://api.open-meteo.com/), specifically the /v1/forecast endpoint.
Requires LLM: Yes
news-api
Tool Name: News API
Tool Description: Use this when you want to get information about the top headlines of current news stories. The input should be a question in natural language that this API can answer.
Notes: A natural language connection to the News API (https://newsapi.org), specifically the /v2/top-headlines endpoint.
Requires LLM: Yes
Extra Parameters: news_api_key (your API key to access this endpoint)
tmdb-api
Tool Name: TMDB API
Tool Description: Useful for when you want to get information from The Movie Database. The input should be a question in natural language that this API can answer.
Notes: A natural language connection to the TMDB API (https://api.themoviedb.org/3), specifically the /search/movie endpoint.
Requires LLM: Yes
Extra Parameters: tmdb_bearer_token (your Bearer Token to access this endpoint - note that this is different from the API key)
google-search
Tool Name: Search
Tool Description: A wrapper around Google Search. Useful for when you need to answer questions about current events. Input should be a search query.
Notes: Uses the Google Custom Search API
Requires LLM: No
Extra Parameters: google_api_key, google_cse_id
For more information on this, see this page
searx-search
Tool Name: Search


For more information on this, see this page
searx-search
Tool Name: Search
Tool Description: A wrapper around SearxNG meta search engine. Input should be a search query.
Notes: SearxNG is easy to deploy self-hosted. It is a good privacy friendly alternative to Google Search. Uses the SearxNG API.
Requires LLM: No
Extra Parameters: searx_host
google-serper
Tool Name: Search
Tool Description: A low-cost Google Search API. Useful for when you need to answer questions about current events. Input should be a search query.
Notes: Calls the serper.dev Google Search API and then parses results.
Requires LLM: No
Extra Parameters: serper_api_key
For more information on this, see this page
wikipedia
Tool Name: Wikipedia
Tool Description: A wrapper around Wikipedia. Useful for when you need to answer general questions about people, places, companies, historical events, or other subjects. Input should be a search query.
Notes: Uses the wikipedia Python package to call the MediaWiki API and then parses results.
Requires LLM: No
Extra Parameters: top_k_results
podcast-api
Tool Name: Podcast API
Tool Description: Use the Listen Notes Podcast API to search all podcasts or episodes. The input should be a question in natural language that this API can answer.
Notes: A natural language connection to the Listen Notes Podcast API (https://www.PodcastAPI.com), specifically the /search/ endpoint.
Requires LLM: Yes
Extra Parameters: listen_api_key (your api key to access this endpoint)
openweathermap-api
Tool Name: OpenWeatherMap
Tool Description: A wrapper around OpenWeatherMap API. Useful for fetching current weather information for a specified location. Input should be a location string (e.g. London,GB).


Notes: A connection to the OpenWeatherMap API (https://api.openweathermap.org), specifically the /data/2.5/weather endpoint.
Requires LLM: No
Extra Parameters: openweathermap_api_key (your API key to access this endpoint)
sleep
Tool Name: Sleep
Tool Description: Make agent sleep for some time.
Requires LLM: No
previous
Tools
next
Defining Custom Tools
 Contents

List of Tools
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
DuckDuckGo Search
DuckDuckGo Search#
This notebook goes over how to use the duck-duck-go search component.
# !pip install duckduckgo-search
from langchain.tools import DuckDuckGoSearchRun
search = DuckDuckGoSearchRun()
search.run("Obama's first name?")


'Barack Obama, in full Barack Hussein Obama II, (born August 4, 1961, Honolulu, Hawaii, U.S.), 44th president of the United States (2009-17) and the first African American to hold the office. Before winning the presidency, Obama represented Illinois in the U.S. Senate (2005-08). Barack Hussein Obama II (/ b ə ˈ r ɑː k h uː ˈ s eɪ n oʊ ˈ b ɑː m ə / bə-RAHK hoo-SAYN oh-BAH-mə; born August 4, 1961) is an American former politician who served as the 44th president of the United States from 2009 to 2017. A member of the Democratic Party, he was the first African-American president of the United States. Obama previously served as a U.S. senator representing ... Barack Obama was the first African American president of the United States (2009-17). He oversaw the recovery of the U.S. economy (from the Great Recession of 2008-09) and the enactment of landmark health care reform (the Patient Protection and Affordable Care Act ). In 2009 he was awarded the Nobel Peace Prize. His birth certificate lists his first name as Barack: That\'s how Obama has spelled his name throughout his life. His name derives from a Hebrew name which means "lightning.". The Hebrew word has been transliterated into English in various spellings, including Barak, Buraq, Burack, and Barack. Most common names of U.S. presidents 1789-2021. Published by. Aaron O\'Neill , Jun 21, 2022. The most common first name for a U.S. president is James, followed by John and then William. Six U.S ...'
previous


previous
ChatGPT Plugins
next
File System Tools
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
Bing Search
 Contents
Number of results
Metadata Results
Bing Search#
This notebook goes over how to use the bing search component.
First, you need to set up the proper API keys and environment variables. To set it up, follow the instructions found here.
Then we will need to set some environment variables.
import os
os.environ["BING_SUBSCRIPTION_KEY"] = ""
os.environ["BING_SEARCH_URL"] = ""
from langchain.utilities import BingSearchAPIWrapper
search = BingSearchAPIWrapper()
search.run("python")


'Thanks to the flexibility of Python and the powerful ecosystem of packages, the Azure CLI supports features such as autocompletion (in shells that support it), persistent credentials, JMESPath result parsing, lazy initialization, network-less unit tests, and more. Building an open-source and cross-platform Azure CLI with Python by Dan Taylor. Python releases by version number: Release version Release date Click for more. Python 3.11.1 Dec. 6, 2022 Download Release Notes. Python 3.10.9 Dec. 6, 2022 Download Release Notes. Python 3.9.16 Dec. 6, 2022 Download Release Notes. Python 3.8.16 Dec. 6, 2022 Download Release Notes. Python 3.7.16 Dec. 6, 2022 Download Release Notes. In this lesson, we will look at the += operator in Python and see how it works with several simple examples.. The operator ‘+=’ is a shorthand for the addition assignment operator.It adds two values and assigns the sum to a variable (left operand). W3Schools offers free online tutorials, references and exercises in all the major languages of the web. Covering popular subjects like HTML, CSS, JavaScript, Python, SQL, Java, and many, many more. This tutorial introduces the reader informally to the basic concepts and features of the Python language and system. It helps to have a Python interpreter handy for hands-on experience, but all examples are self-contained, so the tutorial can be read off-line as well. For a description of standard objects


self-contained, so the tutorial can be read off-line as well. For a description of standard objects and modules, see The Python Standard ... Python is a general-purpose, versatile, and powerful programming language. It's a great first language because Python code is concise and easy to read. Whatever you want to do, python can do it. From web development to machine learning to data science, Python is the language for you. To install Python using the Microsoft Store: Go to your Start menu (lower left Windows icon), type "Microsoft Store", select the link to open the store. Once the store is open, select Search from the upper-right menu and enter "Python". Select which version of Python you would like to use from the results under Apps. Under the “Python Releases for Mac OS X” heading, click the link for the Latest Python 3 Release - Python 3.x.x. As of this writing, the latest version was Python 3.8.4. Scroll to the bottom and click macOS 64-bit installer to start the download. When the installer is finished downloading, move on to the next step. Step 2: Run the Installer'


Number of results#
You can use the k parameter to set the number of results
search = BingSearchAPIWrapper(k=1)
search.run("python")
'Thanks to the flexibility of Python and the powerful ecosystem of packages, the Azure CLI supports features such as autocompletion (in shells that support it), persistent credentials, JMESPath result parsing, lazy initialization, network-less unit tests, and more. Building an open-source and cross-platform Azure CLI with Python by Dan Taylor.'
Metadata Results#
Run query through BingSearch and return snippet, title, and link metadata.
Snippet: The description of the result.
Title: The title of the result.
Link: The link to the result.
search = BingSearchAPIWrapper()
search.results("apples", 5)
[{'snippet': 'Lady Alice. Pink Lady apples aren’t the only lady in the apple family. Lady Alice apples were discovered growing, thanks to bees pollinating, in Washington. They are smaller and slightly more stout in appearance than other varieties. Their skin color appears to have red and yellow stripes running from stem to butt.',
  'title': '25 Types of Apples - Jessica Gavin',
  'link': 'https://www.jessicagavin.com/types-of-apples/'},
 {'snippet': 'Apples can do a lot for you, thanks to plant chemicals called flavonoids. And they have pectin, a fiber that breaks down in your gut. If you take off the apple’s skin before eating it, you won ...',
  'title': 'Apples: Nutrition & Health Benefits - WebMD',
  'link': 'https://www.webmd.com/food-recipes/benefits-apples'},


{'snippet': 'Apples boast many vitamins and minerals, though not in high amounts. However, apples are usually a good source of vitamin C. Vitamin C. Also called ascorbic acid, this vitamin is a common ...',
  'title': 'Apples 101: Nutrition Facts and Health Benefits',
  'link': 'https://www.healthline.com/nutrition/foods/apples'},
 {'snippet': 'Weight management. The fibers in apples can slow digestion, helping one to feel greater satisfaction after eating. After following three large prospective cohorts of 133,468 men and women for 24 years, researchers found that higher intakes of fiber-rich fruits with a low glycemic load, particularly apples and pears, were associated with the least amount of weight gain over time.',
  'title': 'Apples | The Nutrition Source | Harvard T.H. Chan School of Public Health',
  'link': 'https://www.hsph.harvard.edu/nutritionsource/food-features/apples/'}]
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Shell Tool
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Brave Search
 Contents

Number of results
Metadata Results
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
YouTubeSearchTool
YouTubeSearchTool#
This notebook shows how to use a tool to search YouTube
Adapted from venuv/langchain_yt_tools
#! pip install youtube_search
from langchain.tools import YouTubeSearchTool
tool = YouTubeSearchTool()
tool.run("lex friedman")
"['/watch?v=VcVfceTsD0A&pp=ygUMbGV4IGZyaWVkbWFu', '/watch?v=gPfriiHBBek&pp=ygUMbGV4IGZyaWVkbWFu']"
You can also specify the number of results that are returned
tool.run("lex friedman,5")
"['/watch?v=VcVfceTsD0A&pp=ygUMbGV4IGZyaWVkbWFu', '/watch?v=YVJ8gTnDC4Y&pp=ygUMbGV4IGZyaWVkbWFu', '/watch?v=Udh22kuLebg&pp=ygUMbGV4IGZyaWVkbWFu', '/watch?v=gPfriiHBBek&pp=ygUMbGV4IGZyaWVkbWFu', '/watch?v=L_Guz73e6fw&pp=ygUMbGV4IGZyaWVkbWFu']"
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Wolfram Alpha
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Zapier Natural Language Actions API
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.


.ipynb
.pdf
Requests
 Contents
Inside the tool
Requests#
The web contains a lot of information that LLMs do not have access to. In order to easily let LLMs interact with that information, we provide a wrapper around the Python Requests module that takes in a URL and fetches data from that URL.
from langchain.agents import load_tools
requests_tools = load_tools(["requests_all"])
requests_tools
[RequestsGetTool(name='requests_get', description='A portal to the internet. Use this when you need to get specific content from a website. Input should be a  url (i.e. https://www.google.com). The output will be the text response of the GET request.', args_schema=None, return_direct=False, verbose=False, callbacks=None, callback_manager=None, requests_wrapper=TextRequestsWrapper(headers=None, aiosession=None)),
 RequestsPostTool(name='requests_post', description='Use this when you want to POST to a website.\n    Input should be a json string with two keys: "url" and "data".\n    The value of "url" should be a string, and the value of "data" should be a dictionary of \n    key-value pairs you want to POST to the url.\n    Be careful to always use double quotes for strings in the json string\n    The output will be the text response of the POST request.\n    ', args_schema=None, return_direct=False, verbose=False, callbacks=None, callback_manager=None, requests_wrapper=TextRequestsWrapper(headers=None, aiosession=None)),


RequestsPatchTool(name='requests_patch', description='Use this when you want to PATCH to a website.\n    Input should be a json string with two keys: "url" and "data".\n    The value of "url" should be a string, and the value of "data" should be a dictionary of \n    key-value pairs you want to PATCH to the url.\n    Be careful to always use double quotes for strings in the json string\n    The output will be the text response of the PATCH request.\n    ', args_schema=None, return_direct=False, verbose=False, callbacks=None, callback_manager=None, requests_wrapper=TextRequestsWrapper(headers=None, aiosession=None)),
 RequestsPutTool(name='requests_put', description='Use this when you want to PUT to a website.\n    Input should be a json string with two keys: "url" and "data".\n    The value of "url" should be a string, and the value of "data" should be a dictionary of \n    key-value pairs you want to PUT to the url.\n    Be careful to always use double quotes for strings in the json string.\n    The output will be the text response of the PUT request.\n    ', args_schema=None, return_direct=False, verbose=False, callbacks=None, callback_manager=None, requests_wrapper=TextRequestsWrapper(headers=None, aiosession=None)),
 RequestsDeleteTool(name='requests_delete', description='A portal to the internet. Use this when you need to make a DELETE request to a URL. Input should be a specific url, and the output will be the text response of the DELETE request.', args_schema=None, return_direct=False, verbose=False, callbacks=None, callback_manager=None, requests_wrapper=TextRequestsWrapper(headers=None, aiosession=None))]
Inside the tool#
Each requests tool contains a requests wrapper. You can work with these wrappers directly below


Each requests tool contains a requests wrapper. You can work with these wrappers directly below
# Each tool wrapps a requests wrapper
requests_tools[0].requests_wrapper
TextRequestsWrapper(headers=None, aiosession=None)
from langchain.utilities import TextRequestsWrapper
requests = TextRequestsWrapper()
requests.get("https://www.google.com")


'<!doctype html><html itemscope="" itemtype="http://schema.org/WebPage" lang="en"><head><meta content="Search the world\'s information, including webpages, images, videos and more. Google has many special features to help you find exactly what you\'re looking for." name="description"><meta content="noodp" name="robots"><meta content="text/html; charset=UTF-8" http-equiv="Content-Type"><meta content="/images/branding/googleg/1x/googleg_standard_color_128dp.png" itemprop="image"><title>Google</title><script


!important;}#gbar{height:22px}#guser{padding-bottom:7px !important;text-align:right}.gbh,.gbd{border-top:1px solid #c9d7f1;font-size:1px}.gbh{height:0;position:absolute;top:24px;width:100%}@media all{.gb1{height:22px;margin-right:.5em;vertical-align:top}#gbar{float:left}}a.gb1,a.gb4{text-decoration:underline !important}a.gb1,a.gb4{color:#00c !important}.gbi .gb4{color:#dd8e27 !important}.gbf .gb4{color:#900 !important}\n</style><style>body,td,a,p,.h{font-family:arial,sans-serif}body{margin:0;overflow-y:scroll}#gog{padding:3px 8px 0}td{line-height:.8em}.gac_m td{line-height:17px}form{margin-bottom:20px}.h{color:#1558d6}em{font-weight:bold;font-style:normal}.lst{height:25px;width:496px}.gsfi,.lst{font:18px arial,sans-serif}.gsfs{font:17px arial,sans-serif}.ds{display:inline-box;display:inline-block;margin:3px 0 4px;margin-left:4px}input{font-family:inherit}body{background:#fff;color:#000}a{color:#4b11a8;text-decoration:none}a:hover,a:active{text-decoration:underline}.fl a{color:#1558d6}a:visited{color:#4b11a8}.sblc{padding-top:5px}.sblc a{display:block;margin:2px


a{display:block;margin:2px 0;margin-left:13px;font-size:11px}.lsbb{background:#f8f9fa;border:solid 1px;border-color:#dadce0 #70757a #70757a #dadce0;height:30px}.lsbb{display:block}#WqQANb a{display:inline-block;margin:0 12px}.lsb{background:url(/images/nav_logo229.png) 0 -261px repeat-x;border:none;color:#000;cursor:pointer;height:30px;margin:0;outline:0;font:15px arial,sans-serif;vertical-align:top}.lsb:active{background:#dadce0}.lst:focus{outline:none}</style><script nonce="MXrF0nnIBPkxBza4okrgPA">(function(){window.google.erd={jsr:1,bv:1785,de:true};\nvar h=this||self;var k,l=null!=(k=h.mei)?k:1,n,p=null!=(n=h.sdo)?n:!0,q=0,r,t=google.erd,v=t.jsr;google.ml=function(a,b,d,m,e){e=void 0===e?2:e;b&&(r=a&&a.message);if(google.dl)return google.dl(a,e,d),null;if(0>v){window.console&&console.error(a,d);if(-2===v)throw a;b=!1}else b=!a||!a.message||"Error loading script"===a.message||q>=l&&!m?!1:!0;if(!b)return null;q++;d=d||{};b=encodeURIComponent;var


null;q++;d=d||{};b=encodeURIComponent;var c="/gen_204?atyp=i&ei="+b(google.kEI);google.kEXPI&&(c+="&jexpid="+b(google.kEXPI));c+="&srcpg="+b(google.sn)+"&jsr="+b(t.jsr)+"&bver="+b(t.bv);var f=a.lineNumber;void 0!==f&&(c+="&line="+f);var g=\na.fileName;g&&(0<g.indexOf("-extension:/")&&(e=3),c+="&script="+b(g),f&&g===window.location.href&&(f=document.documentElement.outerHTML.split("\\n")[f],c+="&cad="+b(f?f.substring(0,300):"No script found.")));c+="&jsel="+e;for(var u in d)c+="&",c+=b(u),c+="=",c+=b(d[u]);c=c+"&emsg="+b(a.name+": "+a.message);c=c+"&jsst="+b(a.stack||"N/A");12288<=c.length&&(c=c.substr(0,12288));a=c;m||google.log(0,"",a);return a};window.onerror=function(a,b,d,m,e){r!==a&&(a=e instanceof Error?e:Error(a),void 0===d||"lineNumber"in a||(a.lineNumber=d),void 0===b||"fileName"in a||(a.fileName=b),google.ml(a,!1,void 0,!1,"SyntaxError"===a.name||"SyntaxError"===a.message.substring(0,11)||-1!==a.message.indexOf("Script error")?3:0));r=null;p&&q>=l&&(window.onerror=null)};})();</script></head><body bgcolor="#fff"><script nonce="MXrF0nnIBPkxBza4okrgPA">(function(){var


nonce="MXrF0nnIBPkxBza4okrgPA">(function(){var src=\'/images/nav_logo229.png\';var iesg=false;document.body.onload = function(){window.n && window.n();if (document.images){new Image().src=src;}\nif (!iesg){document.f&&document.f.q.focus();document.gbqf&&document.gbqf.q.focus();}\n}\n})();</script>

<nobr>Search Images Maps Play YouTube News Gmail Drive More »</nobr>

<nobr>Web History


class=gb4>Web History | Settings | Sign in</nobr>

<form action="/search" name="f">

 	<input name="ie" value="ISO-8859-1" type="hidden"><input value="en" name="hl" type="hidden"><input name="source" type="hidden" value="hp"><input name="biw" type="hidden"><input name="bih" type="hidden">
<input class="lst" style="margin:0;padding:5px 8px 0 6px;vertical-align:top;color:#000" autocomplete="off" value="" title="Google Search" maxlength="2048" name="q" size="57">

<input class="lsb" value="Google


class="ds"><input class="lsb" value="Google Search" name="btnG" type="submit"><input class="lsb" id="tsuid_1" value="I\'m Feeling Lucky" name="btnI" type="submit"><input value="AOEireoAAAAAZFAdXGKCXWBK5dlWxPhh8hNPQz1s9YT6" name="iflsig" type="hidden">	Advanced search

<input id="gbv" name="gbv" type="hidden" value="1">


ActiveXObject(d),b="2"}catch(h){}}a=b;if("2"==a&&-1==location.search.indexOf("&gbv=2")){var f=google.gbvu,g=document.getElementById("gbv");g&&(g.value=a);f&&window.setTimeout(function(){location.href=f},0)};}).call(this);</script></form>

Celebrate Asian Pacific American Heritage Month with Google

<span


Asian Pacific American Heritage Month with Google

AdvertisingBusiness SolutionsAbout Google

© 2023 - Privacy - Terms


nonce="MXrF0nnIBPkxBza4okrgPA">(function(){var u=\'/xjs/_/js/k\\x3dxjs.hp.en.q0lHXBfs9JY.O/am\\x3dAAAA6AQAUABgAQ/d\\x3d1/ed\\x3d1/rs\\x3dACT90oE3ek6-fjkab6CsTH0wUEUUPhnExg/m\\x3dsb_he,d\';var amd=0;\nvar e=this||self,f=function(c){return c};var h;var n=function(c,g){this.g=g===l?c:""};n.prototype.toString=function(){return this.g+""};var l={};\nfunction p(){var c=u,g=function(){};google.lx=google.stvsc?g:function(){google.timers&&google.timers.load&&google.tick&&google.tick("load","xjsls");var a=document;var b="SCRIPT";"application/xhtml+xml"===a.contentType&&(b=b.toLowerCase());b=a.createElement(b);a=null===c?"null":void 0===c?"undefined":c;if(void 0===h){var d=null;var m=e.trustedTypes;if(m&&m.createPolicy){try{d=m.createPolicy("goog#html",{createHTML:f,createScript:f,createScriptURL:f})}catch(r){e.console&&e.console.error(r.message)}h=\nd}else h=d}a=(d=h)?d.createScriptURL(a):a;a=new n(a,l);b.src=a instanceof n&&a.constructor===n?a.g:"type_error:TrustedResourceUrl";var k,q;(k=(a=null==(q=(k=(b.ownerDocument&&b.ownerDocument.defaultView||window).document).querySelector)?void


0:q.call(k,"script[nonce]"))?a.nonce||a.getAttribute("nonce")||"":"")&&b.setAttribute("nonce",k);document.body.appendChild(b);google.psa=!0;google.lx=g};google.bx||google.lx()};google.xjsu=u;e._F_jsUrl=u;setTimeout(function(){0<amd?google.caft(function(){return p()},amd):p()},0);})();window._ = window._ || {};window._DumpException = _._DumpException = function(e){throw e;};window._s = window._s || {};_s._DumpException = _._DumpException;window._qs = window._qs || {};_qs._DumpException = _._DumpException;function _F_installCss(c){}\n(function(){google.jl={blt:\'none\',chnk:0,dw:false,dwu:true,emtn:0,end:0,ico:false,ikb:0,ine:false,injs:\'none\',injt:0,injth:0,injv2:false,lls:\'default\',pdt:0,rep:0,snet:true,strt:0,ubm:false,uwp:true};})();(function(){var pmc=\'{\\x22d\\x22:{},\\x22sb_he\\x22:{\\x22agen\\x22:true,\\x22cgen\\x22:true,\\x22client\\x22:\\x22heirloom-hp\\x22,\\x22dh\\x22:true,\\x22ds\\x22:\\x22\\x22,\\x22fl\\x22:true,\\x22host\\x22:\\x22google.com\\x22,\\x22jsonp\\x22:true,\\x22msgs\\x22:{\\x22cibl\\x22:\\x22Clear


Search\\x22,\\x22dym\\x22:\\x22Did you mean:\\x22,\\x22lcky\\x22:\\x22I\\\\u0026#39;m Feeling Lucky\\x22,\\x22lml\\x22:\\x22Learn more\\x22,\\x22psrc\\x22:\\x22This search was removed from your \\\\u003Ca href\\x3d\\\\\\x22/history\\\\\\x22\\\\u003EWeb History\\\\u003C/a\\\\u003E\\x22,\\x22psrl\\x22:\\x22Remove\\x22,\\x22sbit\\x22:\\x22Search by image\\x22,\\x22srch\\x22:\\x22Google Search\\x22},\\x22ovr\\x22:{},\\x22pq\\x22:\\x22\\x22,\\x22rfs\\x22:[],\\x22sbas\\x22:\\x220 3px 8px 0 rgba(0,0,0,0.2),0 0 0 1px rgba(0,0,0,0.08)\\x22,\\x22stok\\x22:\\x22C3TIBpTor6RHJfEIn2nbidnhv50\\x22}}\';google.pmc=JSON.parse(pmc);})();</script>       </body></html>'


previous
Python REPL
next
SceneXplain
 Contents

Inside the tool
By Harrison Chase

      © Copyright 2023, Harrison Chase.

  Last updated on Jun 16, 2023.