I know these are all arxiv.org so far, but if you want to include research papers beyond that plaform, can I encourage you to use DOIs for links? It'll make links persistent and easy to cross-reference with citations and other systems. I did a spot check of the 14 links you have so far all have DOIs. I'm happy to give advice!
I came here as well to recommend the DOI. So many nice things can be had by using this rather than your own IDs, it means that site now becomes a tool that composes with other tools.
The DOI is a natural foreign key, look at semantic scholar and the integrations that arxiv is doing in the bottom 1/3. You are generating your own IDs, so you won't compose with the rest of the ecosystem.
Your keys mean nothing and given a handle to a paper, they can't reference your site.
(I work at Crossref.org)