Altmetric Attention Scores are complementary to traditional, citation-based metrics. (source: https://www.altmetric.com/about-altmetrics/what-are-altmetrics/). A score is calculated for the work rather than the author.
Altmetric Attention Scores for works are available with the bibliographic records in several sources including Dimensions.ai and the SUNY Open Access Repository (after a manuscript has been submitted).
Example of an Altmetric Attention Score:
(Screenshot from Dimensions.ia)