not OP, but for the "unique identifiers", you can think of it like the footnote style of markdown links. Most of these models are fine-tuned to do markdown well, and a short identifier is less likely to be hallucinated (my philosophy anyway), so it usually works pretty well. For the examples, something like this can work
ID: 1
URL: https://example.com/test.html
Text: lksdjflkdsjlksjkl
And then tell it to use the ID to link to the page.