Marvin: a Python library for building AI-powered software

Yesterday we launched a new open-source product called Marvin. Marvin is a library for building AI-powered software and it’s taking off faster than we could have imagined. :rocket: We think you’ll find it helpful in your workflows.

:magic_wand: Marvin’s headline feature is AI Functions. These are minimal functions with typed inputs and outputs and a docstring, but no source code.

Yes. You read that right. There’s no source code required.

Instead, when you call an AI Function, the output is predicted by GPT-4 (or GPT-3.5). We know this sounds :exploding_head: but it works astoundingly well.

You just write the def of a function you wish you had… and then you call it.

To get this magic, just add Marvin’s @ai_fn decorator. Here’s an example:

from marvin import ai_fn 

def spam_rating(email_body: str) -> int: 
    """ Returns a number between 0 and 100 that represents how likely the email is spam """ 

spam_rating("Hey, just following up about dinner tomorrow.") # 17 
spam_rating("Hi, I'm Nigerian prince and I really need your help.") # 95

️Obviously, this is cool. But more importantly, it aligns with Prefect’s product mission to eliminate negative engineering and bring engineers as close as possible to their objectives.

:star: Give Marvin a star on GitHub, join the community in Discord, and stay tuned — AI functions are just the beginning of what it can do.

Happy engineering!
The Prefect Team

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