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Shell (bash)

Giving agents access to the shell is powerful (though risky outside a sandboxed environment).

The LLM can use it to execute any shell commands. A common use case for this is letting the LLM interact with your local file system.

Note: Shell tool does not work with Windows OS.

from langchain.tools import ShellTool

shell_tool = ShellTool()
print(shell_tool.run({"commands": ["echo 'Hello World!'", "time"]}))
Hello World!

real    0m0.000s
user    0m0.000s
sys 0m0.000s
/Users/wfh/code/lc/lckg/langchain/tools/shell/tool.py:34: UserWarning: The shell tool has no safeguards by default. Use at your own risk.
  warnings.warn(

Use with Agents​

As with all tools, these can be given to an agent to accomplish more complex tasks. Let’s have the agent fetch some links from a web page.

from langchain.agents import AgentType, initialize_agent
from langchain_openai import ChatOpenAI

llm = ChatOpenAI(temperature=0)

shell_tool.description = shell_tool.description + f"args {shell_tool.args}".replace(
    "{", "{{"
).replace("}", "}}")
self_ask_with_search = initialize_agent(
    [shell_tool], llm, agent=AgentType.CHAT_ZERO_SHOT_REACT_DESCRIPTION, verbose=True
)
self_ask_with_search.run(
    "Download the langchain.com webpage and grep for all urls. Return only a sorted list of them. Be sure to use double quotes."
)


> Entering new AgentExecutor chain...
Question: What is the task?
Thought: We need to download the langchain.com webpage and extract all the URLs from it. Then we need to sort the URLs and return them.
Action:
```
{
  "action": "shell",
  "action_input": {
    "commands": [
      "curl -s https://langchain.com | grep -o 'http[s]*://[^\" ]*' | sort"
    ]
  }
}
```

Observation: https://blog.langchain.dev/
https://discord.gg/6adMQxSpJS
https://docs.langchain.com/docs/
https://github.com/hwchase17/chat-langchain
https://github.com/hwchase17/langchain
https://github.com/hwchase17/langchainjs
https://github.com/sullivan-sean/chat-langchainjs
https://js.langchain.com/docs/
https://python.langchain.com/en/latest/
https://twitter.com/langchainai

Thought:The URLs have been successfully extracted and sorted. We can return the list of URLs as the final answer.
Final Answer: ["https://blog.langchain.dev/", "https://discord.gg/6adMQxSpJS", "https://docs.langchain.com/docs/", "https://github.com/hwchase17/chat-langchain", "https://github.com/hwchase17/langchain", "https://github.com/hwchase17/langchainjs", "https://github.com/sullivan-sean/chat-langchainjs", "https://js.langchain.com/docs/", "https://python.langchain.com/en/latest/", "https://twitter.com/langchainai"]

> Finished chain.
/Users/wfh/code/lc/lckg/langchain/tools/shell/tool.py:34: UserWarning: The shell tool has no safeguards by default. Use at your own risk.
  warnings.warn(
'["https://blog.langchain.dev/", "https://discord.gg/6adMQxSpJS", "https://docs.langchain.com/docs/", "https://github.com/hwchase17/chat-langchain", "https://github.com/hwchase17/langchain", "https://github.com/hwchase17/langchainjs", "https://github.com/sullivan-sean/chat-langchainjs", "https://js.langchain.com/docs/", "https://python.langchain.com/en/latest/", "https://twitter.com/langchainai"]'