After searching for a DOI or PMID you will be taken to the LibKey landing page. If the full text of an article is available, you will be able to choose to view either the PDF (Portable Document Format) or the HTML version. For some articles, the PDF may not be available but you can still go to the HTML version on the journal's platform.
LibKey also provides a link to view an article in context. This takes you to the table of contents for the journal issue your article appears in, increasing the discoverability of similar articles from the same publication.