diff --git a/docs/content/About-Experimental-Features.md b/docs/content/About-Experimental-Features.md
index 5fe74527bc3..e99dbc60828 100644
--- a/docs/content/About-Experimental-Features.md
+++ b/docs/content/About-Experimental-Features.md
@@ -3,3 +3,12 @@ layout: doc_page
 ---
 # About Experimental Features
 Experimental features are features we have developed but have not fully tested in a production environment. If you choose to try them out, there will likely be edge cases that we have not covered. We would love feedback on any of these features, whether they are bug reports, suggestions for improvement, or letting us know they work as intended.
+
+
+To enable experimental features, include their artifacts in the configuration runtime.properties file. Eg-
+
+```
+druid.extensions.coordinates=["io.druid.extensions:druid-histogram:{VERSION}"]
+```
+
+The configuration for all the indexer and query nodes need to be updated with this.
diff --git a/docs/content/Firehose.md b/docs/content/Firehose.md
index ebe15b3632a..065ba2472c1 100644
--- a/docs/content/Firehose.md
+++ b/docs/content/Firehose.md
@@ -50,9 +50,7 @@ A sample ingest firehose spec is shown below -
 {
     "type"    : "ingestSegment",
     "dataSource"   : "wikipedia",
-    "interval" : "2013-01-01/2013-01-02",
-    "dimensions":[],
-    "metrics":[]
+    "interval" : "2013-01-01/2013-01-02"
 }
 ```
 
@@ -61,8 +59,8 @@ A sample ingest firehose spec is shown below -
 |type|ingestSegment. Type of firehose|yes|
 |dataSource|A String defining the data source to fetch rows from, very similar to a table in a relational database|yes|
 |interval|A String representing ISO-8601 Interval. This defines the time range to fetch the data over.|yes|
-|dimensions|The list of dimensions to select. If left empty, all dimensions are selected.|no|
-|metrics|The list of metrics to select. If left empty, all metrics are returned.|no|
+|dimensions|The list of dimensions to select. If left empty, no dimensions are returned. If left null or not defined, all dimensions are returned. |no|
+|metrics|The list of metrics to select. If left empty, no metrics are returned. If left null or not defined, all metrics are selected.|no|
 |filter| See [Filters](Filters.html)|yes|