diff --git a/core/api/src/main/java/org/onosproject/net/pi/model/PiActionParamModel.java b/core/api/src/main/java/org/onosproject/net/pi/model/PiActionParamModel.java
index 284d2b2..ff504be 100644
--- a/core/api/src/main/java/org/onosproject/net/pi/model/PiActionParamModel.java
+++ b/core/api/src/main/java/org/onosproject/net/pi/model/PiActionParamModel.java
@@ -33,8 +33,17 @@
 
     /**
      * Return the size in bits of this action parameter.
+     * It returns -1 if the bit width of the action parameters is not predefined.
      *
-     * @return size in bits
+     * @return size in bits, -1 if not predefined
      */
     int bitWidth();
+
+    /**
+     * Return true is the action parameters has a predefined bit width.
+     * It returns false if it can have arbitrary bit width.
+     *
+     * @return True if the action parameter has predefined bit width, false otherwise
+     */
+    boolean hasBitWidth();
 }
diff --git a/core/api/src/main/java/org/onosproject/net/pi/model/PiMatchFieldModel.java b/core/api/src/main/java/org/onosproject/net/pi/model/PiMatchFieldModel.java
index 57d817a..16020ce 100644
--- a/core/api/src/main/java/org/onosproject/net/pi/model/PiMatchFieldModel.java
+++ b/core/api/src/main/java/org/onosproject/net/pi/model/PiMatchFieldModel.java
@@ -33,12 +33,21 @@
 
     /**
      * Returns the number of bits matched by this field.
+     * It returns -1 if the bit width of the match field is not predefined.
      *
-     * @return number of bits
+     * @return number of bits, -1 in case it is not predefined
      */
     int bitWidth();
 
     /**
+     * Return true is the match field has a predefined bit width.
+     * It returns false if it can have arbitrary bit width.
+     *
+     * @return True if the match field has predefined bit width, false otherwise
+     */
+    boolean hasBitWidth();
+
+    /**
      * Returns the type of match applied to this field.
      *
      * @return a match type