¿What should I include in user stories for developers?

It's my first time working on a digital product development project, I kind of have an idea of how the process works, but its just like "theory" knowledge, not practical knowledge, so I would be very grateful if you guys can recommend me how to give developers the product requirements, we will be working with Agile (scrum) methodology, so I'm supposed to write user stories for developers along with other team members, but I don't know best practices, and useful things that you developers find attractive and well useful.

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Thank you all!