do_action( 'rest_api_init', WP_REST_Server $server )

add_action( 'rest_api_init', function( $server ) {
    register_rest_route( 'my-plugin/v1', '/items', array(
        'methods'             => 'GET',
        'callback'            => 'get_items',
        'permission_callback' => '__return_true',
    ) );
} );

apply_filters( 'rest_authentication_errors', WP_Error|null|true $errors )

add_filter( 'rest_authentication_errors', function( $result ) {
    // Skip if another method authenticated
    if ( true === $result || is_wp_error( $result ) ) {
        return $result;
    }
    
    // Custom auth check
    $token = $_SERVER['HTTP_X_API_KEY'] ?? '';
    if ( $token === 'secret' ) {
        return true;
    }
    
    return new WP_Error( 'invalid_key', 'Invalid API key', array( 'status' => 401 ) );
} );

apply_filters( 'rest_pre_dispatch', mixed $result, WP_REST_Server $server, WP_REST_Request $request )

add_filter( 'rest_pre_dispatch', function( $result, $server, $request ) {
    // Rate limiting
    if ( is_rate_limited( $request ) ) {
        return new WP_Error( 'rate_limited', 'Too many requests', array( 'status' => 429 ) );
    }
    return $result;
}, 10, 3 );

apply_filters( 'rest_request_before_callbacks', WP_REST_Response|WP_Error|mixed $response, array $handler, WP_REST_Request $request )

apply_filters( 'rest_dispatch_request', mixed $dispatch_result, WP_REST_Request $request, string $route, array $handler )

apply_filters( 'rest_request_after_callbacks', WP_REST_Response|WP_Error|mixed $response, array $handler, WP_REST_Request $request )

add_filter( 'rest_request_after_callbacks', function( $response, $handler, $request ) {
    // Add timing header
    if ( $response instanceof WP_REST_Response ) {
        $response->header( 'X-Request-Time', microtime( true ) - $_SERVER['REQUEST_TIME_FLOAT'] );
    }
    return $response;
}, 10, 3 );

apply_filters( 'rest_post_dispatch', WP_HTTP_Response $result, WP_REST_Server $server, WP_REST_Request $request )

add_filter( 'rest_post_dispatch', function( $response, $server, $request ) {
    // Modify all responses
    $data = $response->get_data();
    $data['api_version'] = '2.0';
    $response->set_data( $data );
    return $response;
}, 10, 3 );

apply_filters( 'rest_pre_serve_request', bool $served, WP_HTTP_Response $result, WP_REST_Request $request, WP_REST_Server $server )

apply_filters( 'rest_pre_echo_response', array $result, WP_REST_Server $server, WP_REST_Request $request )

apply_filters( 'rest_envelope_response', array $envelope, WP_REST_Response $response )

apply_filters( 'rest_url_prefix', string $prefix )

apply_filters( 'rest_url', string $url, string $path, int $blog_id, string $scheme )

apply_filters( 'rest_endpoints', array $endpoints )

apply_filters( 'rest_endpoints_description', array $data )

apply_filters( 'rest_route_data', array[] $available, array $routes )

apply_filters( 'rest_index', WP_REST_Response $response, WP_REST_Request $request )

apply_filters( 'rest_namespace_index', WP_REST_Response $response, WP_REST_Request $request )

apply_filters( 'rest_exposed_cors_headers', string[] $expose_headers, WP_REST_Request $request )

apply_filters( 'rest_allowed_cors_headers', string[] $allow_headers, WP_REST_Request $request )

apply_filters( 'rest_json_encode_options', int $options, WP_REST_Request $request )

apply_filters( 'rest_jsonp_enabled', bool $enabled )

apply_filters( 'rest_route_for_post', string $route, WP_Post $post )

apply_filters( 'rest_route_for_post_type_items', string $route, WP_Post_Type $post_type )

apply_filters( 'rest_route_for_term', string $route, WP_Term $term )

apply_filters( 'rest_route_for_taxonomy_items', string $route, WP_Taxonomy $taxonomy )

apply_filters( 'rest_queried_resource_route', string $route )

apply_filters( 'rest_send_nocache_headers', bool $send )

apply_filters( 'rest_avatar_sizes', int[] $sizes )

apply_filters( 'rest_request_parameter_order', string[] $order, WP_REST_Request $request )

apply_filters( 'rest_request_from_url', WP_REST_Request|false $request, string $url )

apply_filters( 'rest_response_link_curies', array $additional )

apply_filters( 'rest_get_max_batch_size', int $max_size )

apply_filters( 'wp_is_rest_endpoint', bool $is_rest_endpoint )

apply_filters( 'wp_rest_server_class', string $class_name )

apply_filters( 'wp_rest_search_handlers', WP_REST_Search_Handler[] $handlers )