WordPress at a glance
filter is not described

rest_namespace_index filter-hook . WP 4.4.0

Filters the namespace index data.

This typically is just the route data for the namespace, but you can add any data you'd like here.

Usage

add_filter( 'rest_namespace_index', 'filter_function_name_7548', 10, 2 );
function filter_function_name_7548( $response, $request ){
	// filter...

	return $response;
}
$response(WP_REST_Response)
Response data.
$request(WP_REST_Request)
Request data. The namespace is passed as the 'namespace' parameter.

Where the hook is called

WP_REST_Server::get_namespace_index()
rest_namespace_index
wp-includes/rest-api/class-wp-rest-server.php 1088
return apply_filters( 'rest_namespace_index', $response, $request );

Where the hook is used (in WP core)

Does not used.