\DocumentMetadata{testphase={phase-III,title,table,math,firstaid},lang=en-US}
\documentclass{article}
\usepackage{hyperref}
\title{A Tagged Contribution}
\author{Example Author}
\begin{document}
\tagstructbegin{tag=Part}
\tagstructbegin{tag=H2,title={A Tagged Contribution}}\tagmcbegin{tag=H2,actualtext={A Tagged Contribution}}\section*{A Tagged Contribution}\tagmcend\tagstructend
\tagstructbegin{tag=Sect}
\tagstructbegin{tag=H3,title={Introduction}}\tagmcbegin{tag=H3,actualtext={Introduction}}\subsection*{Introduction}\tagmcend\tagstructend
\tagstructbegin{tag=P}\tagmcbegin{tag=P}This is a tagged paragraph on the first page.
Continue with the \hyperlink{second-page}{second page}, visit the
\href{https://example.org/tagpax?source=test}{project site}, or open the
\href{other.pdf}{external PDF}.\tagmcend\tagstructend
\newpage
\hypertarget{second-page}{}
\tagstructbegin{tag=H3,title={Second page}}\tagmcbegin{tag=H3,actualtext={Second page}}\subsection*{Second page}\tagmcend\tagstructend
\tagstructbegin{tag=P}\tagmcbegin{tag=P}This is a tagged paragraph on the second page.\tagmcend\tagstructend
\tagstructend
\tagstructend
\end{document}