How to define tools in LangChain.

langchain_tool_definition.py

from langchain.agents import Tool


tools = [
    Tool(
        name="play_action",
        func=play_a_song,
        description="Useful when you want to play one song via the spotify api. "
                    "Try to find a single song that fits best to the prompt of the user! "
                    "This song should be the input to this tool in form of a comma "
                    "separated list of strings of length two! Representing the title and the "
                    "interpreter or album you want to play. For example, `I Was Made For "
                    "Loving You,KISS` would be the input if you wanted to play a specific "
                    "song. Never send multiple songs, only a single one is allowed!"
    ),
    Tool(
        name="search",
        func=search_on_internet,
        description="Useful if you do not know an answer to the users question. "
                    "Then you can use this tool to search for the answer on the Internet. "
                    "The tool requires a search query string as input. Formulate a search "
                    "query ALWAYS as a question!"
    ),
    Tool(
        name="album_info",
        func=get_album_info,
        description="Useful if you want to know which songs are on a particular music album. "
                    "The input to this tool should be the album name and the name of the band."
    )
]