docs: readme

README.md

@@ -1,3 +1,48 @@
 # chobitsu
 
+[![NPM version][npm-image]][npm-url]
+[![Build status][travis-image]][travis-url]
+[![License][license-image]][npm-url]
+
+[npm-image]: https://img.shields.io/npm/v/chobitsu.svg
+[npm-url]: https://npmjs.org/package/chobitsu
+[travis-image]: https://img.shields.io/travis/liriliri/chobitsu.svg
+[travis-url]: https://travis-ci.org/liriliri/chobitsu
+[license-image]: https://img.shields.io/npm/l/chobitsu.svg
+
 Chrome devtools protocol JavaScript implementation.
+
+## Install
+
+You can get it on npm.
+
+```bash
+npm install chobitsu -g
+```
+
+## Usage
+
+```javascript
+const chobitsu = require('chobitsu');
+
+chobitsu.setOnMessage(message => {
+  console.log(message);
+});
+
+chobitsu.sendRawMessage(JSON.stringify({
+  id: 1,  
+  method: 'DOMStorage.clear',
+  params: {
+    storageId: {
+      isLocalStorage: true,
+      securityOrigin: 'http://example.com'
+    }
+  }
+}));
+
+!(async () => {
+  console.log(await chobitsu.sendMessage('Storage.clearDataForOrigin', {
+    storageTypes: 'local_storage'
+  }));
+})();
+```

src/index.ts

@@ -24,7 +24,7 @@ class Chobitsu {
   setOnMessage(onMessage: OnMessage) {
     this.onMessage = onMessage;
   }
-  sendMessage(method: string, params: any) {
+  sendMessage(method: string, params: any = {}) {
     const id = uuid();
 
     this.sendRawMessage(