class WP_REST_Terms_Controller extends WP_REST_Controller {
    protected $taxonomy;
    protected $meta;
    protected $sort_column;
    protected $total_terms;
    protected $allow_batch = array( 'v1' => true );
    
    public function __construct( string $taxonomy );
    public function register_routes();
    
    // Permission Checks
    public function get_items_permissions_check( $request );
    public function get_item_permissions_check( $request );
    public function create_item_permissions_check( $request );
    public function update_item_permissions_check( $request );
    public function delete_item_permissions_check( $request );
    public function check_read_terms_permission_for_post( $post, $request );
    
    // CRUD Operations
    public function get_items( $request );
    public function get_item( $request );
    public function create_item( $request );
    public function update_item( $request );
    public function delete_item( $request );
    
    // Data Preparation
    public function prepare_item_for_database( $request );
    public function prepare_item_for_response( $item, $request );
    protected function prepare_links( $term );
    
    // Schema & Parameters
    public function get_item_schema();
    public function get_collection_params();
    
    // Utilities
    protected function get_term( $id );
    protected function check_is_taxonomy_allowed( $taxonomy );
}

public function __construct( string $taxonomy )

public function check_read_terms_permission_for_post( WP_Post $post, WP_REST_Request $request ): bool

protected function get_term( int $id ): WP_Term|WP_Error

protected function check_is_taxonomy_allowed( string $taxonomy ): bool

public function prepare_item_for_database( WP_REST_Request $request ): object

public function prepare_item_for_response( WP_Term $item, WP_REST_Request $request ): WP_REST_Response

{
    "deleted": true,
    "previous": {
        "id": 123,
        "name": "Category Name",
        "slug": "category-name",
        ...
    }
}

// List categories
$request = new WP_REST_Request( 'GET', '/wp/v2/categories' );
$request->set_param( 'per_page', 100 );
$request->set_param( 'hide_empty', false );
$request->set_param( 'orderby', 'name' );

$controller = new WP_REST_Terms_Controller( 'category' );
$response = $controller->get_items( $request );

// Create a category
$request = new WP_REST_Request( 'POST', '/wp/v2/categories' );
$request->set_param( 'name', 'New Category' );
$request->set_param( 'description', 'Category description' );
$request->set_param( 'parent', 5 ); // Parent category ID

$response = $controller->create_item( $request );

// Get terms for a specific post
$request = new WP_REST_Request( 'GET', '/wp/v2/tags' );
$request->set_param( 'post', 123 );

$controller = new WP_REST_Terms_Controller( 'post_tag' );
$response = $controller->get_items( $request );

// Update a term
$request = new WP_REST_Request( 'POST', '/wp/v2/categories/5' );
$request->set_param( 'name', 'Updated Name' );
$request->set_param( 'slug', 'updated-slug' );

$response = $controller->update_item( $request );

// Delete a term
$request = new WP_REST_Request( 'DELETE', '/wp/v2/categories/5' );
$request->set_param( 'force', true );

$response = $controller->delete_item( $request );

register_taxonomy( 'genre', 'post', array(
    'public'       => true,
    'show_in_rest' => true,
    'rest_base'    => 'genres',
    'hierarchical' => true,
    'labels'       => array(
        'name' => 'Genres',
        'singular_name' => 'Genre',
    ),
));

// Endpoint automatically available at /wp/v2/genres

{
    "code": "term_exists",
    "message": "A term with the name provided already exists with this parent.",
    "data": {
        "status": 400,
        "term_id": 123
    }
}

register_taxonomy( 'custom_tax', 'post', array(
    'show_in_rest' => true,
    'args'         => array(
        'orderby' => 'term_order',
    ),
));