diff --git a/src/json.hpp b/src/json.hpp
index 5987b385..f7af945a 100644
--- a/src/json.hpp
+++ b/src/json.hpp
@@ -833,7 +833,8 @@ struct to_json_fn
     template<typename BasicJsonType, typename T>
     void call(BasicJsonType&, T&&, priority_tag<0>) const noexcept
     {
-        static_assert(sizeof(BasicJsonType) == 0, "to_json method in T's namespace can not be called");
+        static_assert(sizeof(BasicJsonType) == 0,
+                      "could not find to_json() method in T's namespace");
     }
 
   public:
@@ -859,7 +860,8 @@ struct from_json_fn
     template<typename BasicJsonType, typename T>
     void call(const BasicJsonType&, T&, priority_tag<0>) const noexcept
     {
-        static_assert(sizeof(BasicJsonType) == 0, "from_json method in T's namespace can not be called");
+        static_assert(sizeof(BasicJsonType) == 0,
+                      "could not find from_json() method in T's namespace");
     }
 
   public:
diff --git a/src/json.hpp.re2c b/src/json.hpp.re2c
index 0a7f207d..039fc9fb 100644
--- a/src/json.hpp.re2c
+++ b/src/json.hpp.re2c
@@ -833,7 +833,8 @@ struct to_json_fn
     template<typename BasicJsonType, typename T>
     void call(BasicJsonType&, T&&, priority_tag<0>) const noexcept
     {
-        static_assert(sizeof(BasicJsonType) == 0, "to_json method in T's namespace can not be called");
+        static_assert(sizeof(BasicJsonType) == 0,
+                      "could not find to_json() method in T's namespace");
     }
 
   public:
@@ -859,7 +860,8 @@ struct from_json_fn
     template<typename BasicJsonType, typename T>
     void call(const BasicJsonType&, T&, priority_tag<0>) const noexcept
     {
-        static_assert(sizeof(BasicJsonType) == 0, "from_json method in T's namespace can not be called");
+        static_assert(sizeof(BasicJsonType) == 0,
+                      "could not find from_json() method in T's namespace");
     }
 
   public: