diff --git a/README.md b/README.md
index 4f78992..04dbeed 100644
--- a/README.md
+++ b/README.md
@@ -115,6 +115,8 @@ DD_API_KEY=YOUR_KEY_HERE DD_APP_KEY=YOUR_KEY_HERE node app.js
   * update the tags associated with the given `host`
 * `dogapi.detach_tags(host, [[source], callback])`
   * method to remove tags for a given `host`
+* `dogapi.add_snapshot(snapshot, [callback])`
+  * method used to take a snapshot of a datadog graph
 
 ## Sample Usage:
 
diff --git a/lib/api/snapshot.js b/lib/api/snapshot.js
index 890f06b..a2cabed 100644
--- a/lib/api/snapshot.js
+++ b/lib/api/snapshot.js
@@ -9,7 +9,7 @@ var snapshot_api  = function(){};
 
 snapshot_api.prototype.add_snapshot = function(snapshot, callback){
     /*
-     * snapshot_api.add_snapshot(snapshot, callback)
+     * snapshot_api.add_snapshot(snapshot, [callback])
      *
      * method used to add a new snapshot to datadog
      *