Recommendation letters are a necessary evil in academia so I will write one for you, if:

You took a class with me or TA'ed/ULA'ed for a class with me
Your Final Letter Grade in that class was A- or A. If it was B+ or B, I would still write it if you have a good reason for that score.
You have contributed well to the teamwork, participated in discussions and also helped out your fellow classmates
To increases your chances of a better recommendation letter, make sure you participate in all class activities and ask for a recommendation letter early enough i.e. at least a month in advance if not 3

You have an academic misconduct or behavioral misconduct report.
You did something unsavory like being arrogant in your responses to your classmates or TAs on the discussion board or Teams/Slack, even if you were not reported.

Name of the programs you are applying to and their respective deadlines
Your Final Letter grade in all the courses you took with me and the terms that you took them with me
Something noteworthy about your Portfolio project or the course work – e.g. extending the Portfolio project beyond classroom. If you can't recall that, it's ok to just send me a link to your project on GitHub so that I can take a look.
Any specific mention-worthy interactions with students from your work as a ULA/TA and/or as a student
Feel free to add anything else you would want me to talk about in the letter!
Something that you have done in the course, that as per your knowledge, rarely do students do or are expected to do
Your prononuns! I need to know this because as you have probably learned by now, names are not great indicator of gender, among a lot of other things. Also, I would like to honor your preferences!

Now, if you were a TA/ULA for me, please add:

One or two notable things that you did/interactions you had with the students whether in office hours or grading
Why you decided to be a TA/ULA for the course
Again, feel free to add anything else you would want me to talk about in the letter

All the above applies, but if you haven't been a TA/ULA for me, my word would usually not carry much weight even if you had an A in my class. So you should first contact the Prof whom you have worked with a TA/ULA :)