diff --git a/src/Tooltip.tsx b/src/Tooltip.tsx
index 03e9099..eb02806 100644
--- a/src/Tooltip.tsx
+++ b/src/Tooltip.tsx
@@ -4,28 +4,132 @@ import { AlignType, AnimationType, ActionType } from 'rc-trigger/lib/interface';
 import { placements } from './placements';
 import Content from './Content';
 
+/**
+ * Where to place the tooltop. One of
+ * 'left' |'right' |'top' |'bottom' | 'topLeft' | 'topRight' | 'bottomLeft' | 'bottomRight';
+ */
+type Placement =
+  | 'left'
+  | 'right'
+  | 'top'
+  | 'bottom'
+  | 'topLeft'
+  | 'topRight'
+  | 'bottomLeft'
+  | 'bottomRight';
+
 export interface TooltipProps extends Pick<TriggerProps, 'onPopupAlign' | 'builtinPlacements'> {
-  trigger?: ActionType;
-  defaultVisible?: boolean;
-  visible?: boolean;
-  placement?: string;
-  transitionName?: string;
-  animation?: AnimationType;
-  onVisibleChange?: (visible: boolean) => void;
+  /**
+   * Call after visible is changed
+   */
   afterVisibleChange?: () => void;
-  overlay: (() => React.ReactNode) | React.ReactNode;
-  overlayStyle?: React.CSSProperties;
-  overlayClassName?: string;
-  prefixCls?: string;
-  mouseEnterDelay?: number;
-  mouseLeaveDelay?: number;
-  getTooltipContainer?: (node: HTMLElement) => HTMLElement;
-  destroyTooltipOnHide?: boolean;
+  /**
+   * value will be merged into placement's config
+   */
   align?: AlignType;
+
+  /**
+   *
+   */
+  animation?: AnimationType;
+
+  /**
+   * Arrow content, a react component
+   * @default null
+   */
   arrowContent?: React.ReactElement;
-  id?: string;
+
   children?: React.ReactElement;
+
+  /**
+   * Whether tooltip is visible initially
+   * @efaults false
+   */
+  defaultVisible?: boolean;
+
+  /**
+   * Whether destroy tooltip when tooltip is hidden
+   * @default false
+   */
+  destroyTooltipOnHide?: boolean;
+
+  /**
+   * Function returning html node which will act as tooltip container.
+   * By default the tooltip attaches to the body.
+   * If you want to change the container, simply return a new element.
+   */
+  getTooltipContainer?: (node: HTMLElement) => HTMLElement;
+
+  /**
+   * Id which gets attached to the tooltip content.
+   * Can be used with aria-describedby to achieve Screenreader-Support.
+   */
+  id?: string;
+
+  /**
+   * Delay time to show when mouse enter.unit: s.
+   * @default 0
+   */
+  mouseEnterDelay?: number;
+
+  /**
+   * Delay time to hide when mouse leave.unit: s.
+   * @default 0.1
+   */
+  mouseLeaveDelay?: number;
+
+  /**
+   * Call when visible is changed
+   */
+  onVisibleChange?: (visible: boolean) => void;
+
+  /**
+   * React component to render in the popup
+   */
+  overlay: (() => React.ReactNode) | React.ReactNode;
+
+  /**
+   * Additional className added to popup overlay
+   */
+  overlayClassName?: string;
+
+  /**
+   * Additional style of overlay node
+   */
+  overlayStyle?: React.CSSProperties;
+
+  /**
+   * Where to place the tooltop. One of
+   * 'left' |'right' |'top' |'bottom' | 'topLeft' | 'topRight' | 'bottomLeft' | 'bottomRight';
+   */
+  placement?: Placement;
+
+  /**
+   *
+   */
   popupVisible?: boolean;
+
+  /**
+   * prefix class name.
+   * @default "rc-tooltip"
+   */
+  prefixCls?: string;
+
+  /**
+   * same as https://github.com/react-component/animate
+   */
+  transitionName?: string;
+
+  /**
+   * Which actions cause tooltip shown. enum of 'hover','click','focus'
+   * @default 'hover'
+   */
+  trigger?: ActionType;
+
+  /**
+   * call when visible is changed
+   */
+  visible?: boolean;
 }
 
 const Tooltip = (props: TooltipProps, ref) => {