I have shared content enabled for all campaigns that I dm for, but some subclasses and spells like Oathbreaker and armor of agathys aren't sharing with my players. would like any help resolving this or maybe I'm missing something really stupid.

Do you or somebody in the campaign have those subclasses/spells? They're not free ones so somebody needs to have them purchased.

If you do, and assuming you have the Master Tier subscription, try turning off the Content Sharing then turning it back on.

If that doesn't work, check they are adding their character by using your campaign's Join link.

Quote from Cyb3rM1nd >>

If you do, and assuming you have the Master Tier subscription, try turning off the Content Sharing then turning it back on.

 This usually fixes things. Sharing can bug out sometimes. I think it is cause by buying content or adding characters to the campaign after sharing was enabled. Or it might just be random.

Quote from DxJxC >>

Quote from Cyb3rM1nd >>

If you do, and assuming you have the Master Tier subscription, try turning off the Content Sharing then turning it back on.

 This usually fixes things. Sharing can bug out sometimes. I think it is cause by buying content or adding characters to the campaign after sharing was enabled. Or it might just be random.

 
Probably the former. I think when the sharing is enabled the code behind it goes "great, this is what gets shared" and makes the list, it's possible purchases after that might not auto-update that list. Toggling off erases the list and toggling back on recreates the list now with more to add. Or something along those lines.

There's probably a better way to handle it but that would be more complicated to code up and the devs are pushed to their limits as it is, so I don't blame them going with a much simpler solution that occasionally has this small glitch that easily sorted by the good old fashion tech support question: "have you tried turning it off and on again?" (which does solve a surprising number of things, there's a reason the computer restarts after an OS update - to refresh lists and tables with the new things).

Quote from Cyb3rM1nd >>

Quote from DxJxC >>

Quote from Cyb3rM1nd >>

If you do, and assuming you have the Master Tier subscription, try turning off the Content Sharing then turning it back on.

 This usually fixes things. Sharing can bug out sometimes. I think it is cause by buying content or adding characters to the campaign after sharing was enabled. Or it might just be random.

 
Probably the former. I think when the sharing is enabled the code behind it goes "great, this is what gets shared" and makes the list, it's possible purchases after that might not auto-update that list. Toggling off erases the list and toggling back on recreates the list now with more to add. Or something along those lines.

There's probably a better way to handle it but that would be more complicated to code up and the devs are pushed to their limits as it is, so I don't blame them going with a much simpler solution that occasionally has this small glitch that easily sorted by the good old fashion tech support question: "have you tried turning it off and on again?" (which does solve a surprising number of things, there's a reason the computer restarts after an OS update - to refresh lists and tables with the new things).

 This all partially fixed the problem. I also have made home-brew subclasses and those now function better. the las problem is with the spell armor of agathys not showing up in other peoples characters or in some of mine. should I just make a home-brew copy at this point? I've bought pretty much all spells so I don't think id consider it stealing.

Home brewing for personal use is fine. If you want to sort out the armor of apathy’s issue,post the url (not the share link) for an affected character. 

Quote from Octopusssi >>

 This all partially fixed the problem. I also have made home-brew subclasses and those now function better. the las problem is with the spell armor of agathys not showing up in other peoples characters or in some of mine. should I just make a home-brew copy at this point? I've bought pretty much all spells so I don't think id consider it stealing.

 
The spell is part of the PHB. Have you purchased either the PHB or the spell? If you go the spell's page, here, do you see the spell or does it tell you to buy it? If you're asked to buy it then you would need to buy it. If you have the physical book then you can always homebrew a copy and this will be shared with your campaign members automatically. 

If you did buy it, can you ensure your campaign members are definitely creating / adding their characters using the campaign join link?