diff --git a/src/challenge-module/challenge-pin.cpp b/src/challenge-module/challenge-pin.cpp
index c5825f9..1aa96ce 100644
--- a/src/challenge-module/challenge-pin.cpp
+++ b/src/challenge-module/challenge-pin.cpp
@@ -115,17 +115,21 @@
 }
 
 JsonSection
-ChallengePin::genChallengeInfo(const std::string& interestType, const std::string& status,
-                               const std::list<std::string>& paramList)
+ChallengePin::doGenSelectParamsJson(const std::string& status,
+                                    const std::list<std::string>& paramList)
 {
   JsonSection result;
-  if (interestType == "_SELECT") {
-    BOOST_ASSERT(paramList.size() == 0);
-  }
-  else if (interestType == "_VALIDATE") {
-    BOOST_ASSERT(paramList.size() == 1);
-    result.put(JSON_PIN_CODE, paramList.front());
-  }
+  BOOST_ASSERT(paramList.size() == 0);
+  return result;
+}
+
+JsonSection
+ChallengePin::doGenValidateParamsJson(const std::string& status,
+                                      const std::list<std::string>& paramList)
+{
+  JsonSection result;
+  BOOST_ASSERT(paramList.size() == 1);
+  result.put(JSON_PIN_CODE, paramList.front());
   return result;
 }
 
diff --git a/src/challenge-module/challenge-pin.hpp b/src/challenge-module/challenge-pin.hpp
index d6094c7..31ea05f 100644
--- a/src/challenge-module/challenge-pin.hpp
+++ b/src/challenge-module/challenge-pin.hpp
@@ -63,8 +63,12 @@
   getValidateRequirements(const std::string& status) override;
 
   JsonSection
-  genChallengeInfo(const std::string& interestType, const std::string& status,
-                   const std::list<std::string>& paramList) override;
+  doGenSelectParamsJson(const std::string& status,
+                        const std::list<std::string>& paramList) override;
+
+  JsonSection
+  doGenValidateParamsJson(const std::string& status,
+                          const std::list<std::string>& paramList) override;
 
 PUBLIC_WITH_TESTS_ELSE_PRIVATE:
   static std::tuple<time::system_clock::TimePoint, std::string, int>