wp-includes/rest-api.php:1037Adds the REST API URL to the WP RSD endpoint.
function rest_output_rsd() { $api_root = get_rest_url(); if ( empty( $api_root ) ) { return; } ?> <api name="WP-API" blogID="1" preferred="false" apiLink="<?php echo esc_url( $api_root ); ?>" /> <?php}Introduced in 4.4.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/rest-api.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.