diff --git a/jc/parsers/arp.py b/jc/parsers/arp.py
index 2cb7163e..107c562d 100644
--- a/jc/parsers/arp.py
+++ b/jc/parsers/arp.py
@@ -3,6 +3,9 @@
 Usage:
     specify --arp as the first argument if the piped input is coming from arp
 
+Compatibility:
+    'linux', 'aix', 'freebsd', 'darwin'
+
 Examples:
 
     $ arp | jc --arp -p
diff --git a/jc/parsers/df.py b/jc/parsers/df.py
index 329f402c..2f54a8f2 100644
--- a/jc/parsers/df.py
+++ b/jc/parsers/df.py
@@ -3,6 +3,9 @@
 Usage:
     specify --df as the first argument if the piped input is coming from df
 
+Compatibility:
+    'linux', 'darwin'
+
 Examples:
 
     $ df | jc --df -p
diff --git a/jc/parsers/dig.py b/jc/parsers/dig.py
index 374116af..a6d7ffea 100644
--- a/jc/parsers/dig.py
+++ b/jc/parsers/dig.py
@@ -3,6 +3,9 @@
 Usage:
     Specify --dig as the first argument if the piped input is coming from dig
 
+Compatibility:
+    'linux', 'darwin', 'cygwin', 'win32', 'aix', 'freebsd'
+
 Examples:
 
     $ dig cnn.com www.cnn.com @205.251.194.64 | jc --dig -p