The OGC API - Tiles draft specification describes an API building block that can enable other OGC API implementations to serve maps or tiled feature data divided into individual tiles. The draft specification includes concepts such as tile matrix sets and tile schemes, although such concepts have been revised to allow for tiling other types of resources, such as vector tiles and not only maps. The OGC API - Tiles draft specification references the OGC Two Dimensional Tile Matrix Set (TMS) standard. The TMS standard defines the rules and requirements for a tile matrix set as a way to index space based on a set of regular grids defining a domain (tile matrix) for a limited list of scales in a Coordinate Reference System (CRS).
The standards can be found at:
OGC API - Tiles draft
Development of the standards takes place on GitHub.