diff --git a/modules/swagger-codegen/src/main/resources/Eiffel/api.mustache b/modules/swagger-codegen/src/main/resources/Eiffel/api.mustache
index 9c08b336862..53a5edc0698 100644
--- a/modules/swagger-codegen/src/main/resources/Eiffel/api.mustache
+++ b/modules/swagger-codegen/src/main/resources/Eiffel/api.mustache
@@ -13,7 +13,7 @@ feature -- API Access
 
 {{#operation}}
 
-	{{operationId}} {{#hasParams}}({{#allParams}}{{paramName}}: {{#required}}{{{dataType}}}{{/required}}{{^required}}detachable {{{dataType}}}{{/required}}{{#hasMore}}; {{/hasMore}}{{/allParams}}){{/hasParams}}{{#returnType}}: detachable {{{returnType}}}{{/returnType}}{{^returnType}}{{/returnType}}
+	{{operationId}} {{#hasParams}}({{#allParams}}{{paramName}}: {{#required}}{{{dataType}}}{{/required}}{{^required}}{{#isPrimitiveType}}{{{dataType}}}{{/isPrimitiveType}}{{^isPrimitiveType}}detachable {{{dataType}}}{{/isPrimitiveType}}{{/required}}{{#hasMore}}; {{/hasMore}}{{/allParams}}){{/hasParams}}{{#returnType}}: detachable {{{returnType}}}{{/returnType}}{{^returnType}}{{/returnType}}
 			-- {{summary}}
 			-- {{notes}}
 			-- {{#allParams}}
@@ -21,6 +21,17 @@ feature -- API Access
 			-- {{/allParams}}
 			-- {{#returnType}}
 			-- Result {{returnType}}{{/returnType}}
+		require
+		{{#allParams}}	
+		{{#hasValidation}}
+		{{#maximum}}
+			{{{paramName}}}_is_less_or_equal_than: {{{paramName}}} <= {{{maximum}}} 
+        {{/maximum}}
+     	{{#minimum}}
+     		{{{paramName}}}_is_greater_or_equal_than: {{{paramName}}} >= {{{minimum}}} 
+        {{/minimum}}
+		{{/hasValidation}}
+		{{/allParams}}	
 		local
   			l_path: STRING
   			l_request: API_CLIENT_REQUEST
diff --git a/modules/swagger-codegen/src/main/resources/Eiffel/api_client.mustache b/modules/swagger-codegen/src/main/resources/Eiffel/api_client.mustache
index 9de50417eb9..9958265883a 100644
--- a/modules/swagger-codegen/src/main/resources/Eiffel/api_client.mustache
+++ b/modules/swagger-codegen/src/main/resources/Eiffel/api_client.mustache
@@ -135,7 +135,7 @@ feature -- Query Parameter Helpers
 			l_delimiter: STRING
 			l_value: STRING
 		do
-			if attached {LIST [STRING_32]} a_value as a_list then
+			if attached {LIST [ANY]} a_value as a_list then
 					-- Collection
 				if a_list.is_empty then
 						-- Return an empty list	
@@ -150,7 +150,7 @@ feature -- Query Parameter Helpers
 					end
 					if l_format.is_case_insensitive_equal ("multi") then
 						across a_list as ic loop
-							Result.force ([a_name, ic.item.as_string_8])
+							Result.force ([a_name, parameter_to_string (ic.item)])
 						end
 					else
 						if l_format.is_case_insensitive_equal ("csv") then
@@ -166,7 +166,7 @@ feature -- Query Parameter Helpers
 						end
 						across a_list as ic  from create l_value.make_empty
 						loop
-							l_value.append (ic.item)
+							l_value.append (parameter_to_string (ic.item))
 							l_value.append (l_delimiter)
 						end
 						l_value.remove_tail (1)
@@ -185,6 +185,61 @@ feature -- Query Parameter Helpers
 		end
 
 
+	parameter_to_string (a_param: detachable ANY): STRING
+			-- return the string representation of the givien object `a_param'.
+		do
+			if a_param = Void then
+				Result := ""
+			else
+				if attached {BOOLEAN} a_param as bool then
+					Result := bool.out
+				elseif attached {NUMERIC} a_param as num then
+					if attached {INTEGER_64} num as i64 then
+						Result := i64.out
+					elseif attached {INTEGER_32} num as i32 then
+						Result := i32.out
+					elseif attached {INTEGER_16} num as i16 then
+						Result := i16.out
+					elseif attached {INTEGER_8} num as i8 then
+						Result := i8.out
+					elseif attached {NATURAL_64} num as n64 then
+						Result := n64.out
+					elseif attached {NATURAL_32} num as n32 then
+						Result := n32.out
+					elseif attached {NATURAL_16} num as n16 then
+						Result := n16.out
+					elseif attached {NATURAL_8} num as n8 then
+						Result := n8.out
+					elseif attached {REAL_64} num as r64 then
+						Result := r64.out
+					elseif attached {REAL_32} num as r32 then
+						Result := r32.out
+					else
+						check is_basic_numeric_type: False end
+					end
+					Result := num.out
+				elseif attached {CHARACTER_8} a_param as ch8 then
+					Result := ch8.out
+				elseif attached {CHARACTER_32} a_param as ch32 then
+					Result := ch32.out
+				elseif attached {POINTER} a_param as ptr then
+					Result := ptr.to_integer_32.out
+				elseif attached {DATE} a_param as date then
+						--TODO improve to support
+						-- date	string	As defined by full-date - RFC3339
+					Result := date.debug_output
+				elseif attached {DATE_TIME} a_param as date_time then
+						-- TODO improve to support
+						-- dateTime	string	date-time	As defined by date-time - RFC3339
+					Result := date_time.date.debug_output
+				else
+					-- Unsupported Object type.
+					Result := ""
+				end
+			end
+		end
+
+
 feature -- Status Report
 
 	is_valid_uri (a_uri: STRING): BOOLEAN
diff --git a/modules/swagger-codegen/src/main/resources/Eiffel/model.mustache b/modules/swagger-codegen/src/main/resources/Eiffel/model.mustache
index 64f0c64e467..aa5e906c448 100644
--- a/modules/swagger-codegen/src/main/resources/Eiffel/model.mustache
+++ b/modules/swagger-codegen/src/main/resources/Eiffel/model.mustache
@@ -74,7 +74,7 @@ feature -- Change Element
         {{#isListContainer}}
         if attached {{name}} as l_{{name}} then
           across l_{{name}} as ic loop
-            Result.append ("%N")
+            Result.append ("%N {{name}}:")
             Result.append (ic.item.out)
             Result.append ("%N")
           end
@@ -82,6 +82,7 @@ feature -- Change Element
         {{/isListContainer}}
         {{#isMapContainer}}
         if attached {{name}} as l_{{name}} then
+          Result.append ("%N{{name}}:")
           across l_{{name}} as ic loop
             Result.append ("%N")
             Result.append ("key:")
@@ -95,7 +96,7 @@ feature -- Change Element
         {{/isMapContainer}}
         {{^isContainer}}
         if attached {{name}} as l_{{name}} then
-          Result.append ("%N")
+          Result.append ("%N{{name}}:")
           Result.append (l_{{name}}.out)
           Result.append ("%N")    
         end