diff --git a/lib/browser.js b/lib/browser.js
index 5d8cabd..6730451 100644
--- a/lib/browser.js
+++ b/lib/browser.js
@@ -116,6 +116,15 @@ Browser.prototype.context = function(selector, fn){
   return this;
 };
 
+/**
+ * Finds or creates/caches a Browser instance associated with the port
+ * and hostname of `uri`. If a new Browser is created, then the source
+ * Browser's User-Agent (if it is set) is copied to the new Browser.
+ * 
+ * @param {Object} uri is an object returned from `require('url').parse(someUrl)`
+ * @return {Browser} the Browser associated with uri
+ * @api public
+ */
 Browser.prototype.hostBrowser = function(uri) {
   var otherHostname = uri.hostname
     , port = uri.port || (uri.protocol === 'https:' ? 443 : (this.port || 80))