XMP (eXtensible Metadata Platform) is a mechanism proposed by
Adobe for embedding document metadata within the document
itself. The metadata is designed to be easy to extract, even by
programs that are oblivious to the document's file format. Most
of Adobe's applications store XMP metadata when saving files.
Now, with the hyperxmp package, it is trivial for LaTeX
document authors to store XMP metadata in their documents as
well. The package integrates seamlessly with hyperref and
requires virtually no modifications to documents that already
exploit hyperref's mechanisms for specifying PDF metadata. The
current version of hyperxmp can embed the following metadata as
XMP: title, authors, primary author's title or position,
metadata writer, subject/summary, keywords, copyright, license
URL, document base URL, document identifier and instance
identifier, language, source file name, PDF generating tool,
PDF version, and contact telephone number/postal address/email
address/URL. Hyperxmp currently embeds XMP only within PDF
documents; it is compatible with pdfLaTeX, XeLaTeX,
LaTeX+dvipdfm, and LaTeX+dvips+ps2pdf.

Homepage:
https://ctan.org/pkg/hyperxmp
