Custom Content Types

• Set show_in_rest => true in register_post_type() to expose in wp/v2.
• Use rest_base to change the route slug.
• Optionally set rest_controller_class (must extend WP_REST_Controller).

Custom taxonomies

• Set show_in_rest => true in register_taxonomy().
• Use rest_base and optional rest_controller_class (default WP_REST_Terms_Controller).

Adding REST support to existing types

• Use register_post_type_args or register_taxonomy_args filters to enable show_in_rest for types you do not control.

Discovery links for custom controllers

• If you use a custom controller class, use rest_route_for_post or rest_route_for_term filters to map objects to routes.