diff --git a/src/lib/format-util.hpp b/src/lib/format-util.hpp
index 3d84cf024..77940543d 100644
--- a/src/lib/format-util.hpp
+++ b/src/lib/format-util.hpp
@@ -215,5 +215,14 @@ namespace util {
   }
   
   
+  /** shortcut: List in parentheses, separated by comma, using temporary vector */
+  template<typename...ARGS>
+  inline string
+  joinArgList (ARGS const& ...args)
+  {
+    return "("+join (stringify<std::vector<string>> (args...))+")";
+  }
+  
+  
 } // namespace util
 #endif /*LIB_FORMAT_UTIL_H*/
diff --git a/tests/vault/gear/activity-detector-test.cpp b/tests/vault/gear/activity-detector-test.cpp
index b0e48063c..2e27279b3 100644
--- a/tests/vault/gear/activity-detector-test.cpp
+++ b/tests/vault/gear/activity-detector-test.cpp
@@ -67,7 +67,8 @@ namespace test {
         {
           simpleUsage();
           
-          verifyDummyFuncttor();
+          verifyMockInvocation();
+          verifyDummyJobFunctor();
           detect_activation();
           detect_gate();
         }
@@ -92,11 +93,40 @@ namespace test {
       
       
       
+      /** @test verify the setup and detection of instrumented invocations
+       * @todo WIP 7/23 ⟶ define ⟶ implement
+       */
+      void
+      verifyMockInvocation()
+        {
+          ActivityDetector detector;
+          auto fun = detector.buildDiagnosticFun<void(uint)>("funny");
+          uint rnd = rand() % 10000;
+          
+          ++detector;
+          CHECK (1 == detector.currSeq());
+          CHECK (not detector.verifyInvocation ("funny"));
+          
+          detector.markSequence();
+          fun(rnd);
+          detector.markSequence();
+          CHECK (detector.verifyInvocation ("funny"));
+          CHECK (detector.verifyInvocation ("funny", rnd));
+          CHECK (detector.verifyInvocation ("funny", Seq(1)));
+          CHECK (detector.verifyInvocation ("funny", Seq(1), rnd));
+          CHECK (not detector.verifyInvocation ("bunny"));
+          CHECK (not detector.verifyInvocation ("funny", -rnd));
+          CHECK (not detector.verifyInvocation ("funny", Seq(5)));
+          CHECK (not detector.verifyInvocation ("funny", rnd, Seq(1)));
+        }
+      
+      
+      
       /** @test TODO diagnostic setup to detect a JobFunctor activation
        * @todo WIP 7/23 ⟶ define ⟶ implement
        */
       void
-      verifyDummyFuncttor()
+      verifyDummyJobFunctor()
         {
         }
       
diff --git a/tests/vault/gear/activity-detector.hpp b/tests/vault/gear/activity-detector.hpp
index 73a41be24..d2833df13 100644
--- a/tests/vault/gear/activity-detector.hpp
+++ b/tests/vault/gear/activity-detector.hpp
@@ -62,6 +62,7 @@
 //#include "lib/linked-elements.hpp"
 #include "lib/meta/variadic-helper.hpp"
 #include "lib/wrapper.hpp"
+#include "lib/format-cout.hpp"
 #include "lib/format-util.hpp"
 //#include "lib/itertools.hpp"
 //#include "lib/depend.hpp"
@@ -94,6 +95,45 @@ namespace test {
 //  using vault::gear::JobClosure;
   
   
+  /** Marker for invocation sequence */
+  class Seq
+    {
+      uint step_;
+      
+    public:
+      Seq (uint start =0)
+        : step_{start}
+        { }
+      
+      operator uint()  const
+        {
+          return step_;
+        }
+      operator string()  const
+        {
+          return util::toString (step_);
+        }
+      
+      uint
+      operator++()
+        {
+          ++step_;
+          return step_;
+        }
+      
+      bool
+      operator== (Seq const& o)
+        {
+          return step_ == o.step_;
+        }
+    };
+  
+  
+  namespace {// Event markers
+    const string MARK_INC{"Inc"};
+    const string MARK_SEQ{"Seq"};
+  }
+  
   
   /**
    * Diagnostic context to record and evaluate activations within the Scheduler.
@@ -105,6 +145,7 @@ namespace test {
       using EventLog = lib::test::EventLog;
       
       EventLog eventLog_;
+      Seq invocationSeq_;
       
       /**
        * A Mock functor, logging all invocations into the EventLog
@@ -126,10 +167,11 @@ namespace test {
             { }
           
           /** prepare a response value to return from the mock invocation */
+          template<typename VAL>
           DiagnosticFun&&
-          returning (RET&& riggedResponse)
+          returning (VAL&& riggedResponse)
             {
-              retVal_ = std::forward<RET> (riggedResponse);
+              retVal_ = std::forward<VAL> (riggedResponse);
               return std::move (*this);
             }
           
@@ -144,8 +186,9 @@ namespace test {
       
       
     public:
-      ActivityDetector(string id)
+      ActivityDetector(string id ="")
         : eventLog_{"ActivityDetector" + (isnil (id)? string{}: "("+id+")")}
+        , invocationSeq_{0}
         { }
       
       operator string()  const
@@ -162,6 +205,28 @@ namespace test {
             eventLog_.clear (newID);
         }
       
+      uint
+      operator++()
+        {
+          ++invocationSeq_;
+          eventLog_.event (MARK_INC, invocationSeq_);
+          return invocationSeq_;
+        }
+      
+      uint
+      currSeq()  const
+        {
+          return invocationSeq_;
+        }
+      
+      uint
+      markSequence()
+        {
+          eventLog_.event (MARK_SEQ, invocationSeq_);
+          return operator++();
+        }
+      
+      
       /**
        * Generic testing helper: build a λ-mock, logging all invocations
        * @tparam SIG signature of the functor to be generated
@@ -181,6 +246,36 @@ namespace test {
           return Functor{id, eventLog_};
         }
       
+      template<typename...ARGS>
+      bool
+      verifyInvocation (string fun, Seq const& seq, ARGS const& ...args)
+        {
+          bool valid = eventLog_.verifyEvent(seq).id(MARK_INC)
+                                .beforeCall(fun).arg(args...)
+                                .beforeEvent(seq).id(MARK_SEQ);
+          if (not valid)
+            {
+              cerr << "FAIL___Function_invocation___________"
+                   << "\nfunction:"<<fun<<util::joinArgList (args...)
+                   << "\nsequence:"<<seq
+                   << "\n_______Event-Log_____________________\n"
+                   << util::join(eventLog_, "\n")
+                   << "\n───────╼━━━━━━━━╾────────────────────"
+                   << endl;
+            }
+          return valid;
+        }
+      
+      template<typename...ARGS>
+      bool
+      verifyInvocation (string fun, ARGS const& ...args)
+        {
+          Seq currentEventSeq = invocationSeq_;
+          markSequence();       // NOTE: incrementing here
+          return verifyInvocation (fun, currentEventSeq, args...);
+        }
+      
+      
     private:
     };
   
diff --git a/wiki/thinkPad.ichthyo.mm b/wiki/thinkPad.ichthyo.mm
index 808ec20c1..ce8a21eb1 100644
--- a/wiki/thinkPad.ichthyo.mm
+++ b/wiki/thinkPad.ichthyo.mm
@@ -81700,7 +81700,7 @@ Date:&#160;&#160;&#160;Thu Apr 20 18:53:17 2023 +0200<br/>
 </node>
 <node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1690891585410" ID="ID_1976653650" MODIFIED="1690891593537" TEXT="Action-Hook">
 <icon BUILTIN="flag-yellow"/>
-<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1690891602401" ID="ID_1359624247" MODIFIED="1690896708168" TEXT="als Primitive einf&#xfc;hren">
+<node COLOR="#435e98" CREATED="1690891602401" ID="ID_1359624247" MODIFIED="1690899606451" TEXT="als Primitive einf&#xfc;hren">
 <richcontent TYPE="NOTE"><html>
   <head/>
   <body>
@@ -81713,9 +81713,49 @@ Date:&#160;&#160;&#160;Thu Apr 20 18:53:17 2023 +0200<br/>
 <linktarget COLOR="#759db4" DESTINATION="ID_1359624247" ENDARROW="Default" ENDINCLINATION="446;-43;" ID="Arrow_ID_265182299" SOURCE="ID_642006957" STARTARROW="None" STARTINCLINATION="1008;65;"/>
 <icon BUILTIN="yes"/>
 </node>
+<node BACKGROUND_COLOR="#e0ceaa" COLOR="#690f14" CREATED="1690899608350" ID="ID_1677406479" MODIFIED="1690899761758" TEXT="mu&#xdf; Downcast auf konkreten Execution-context machen">
+<richcontent TYPE="NOTE"><html>
+  <head/>
+  <body>
+    <p>
+      geht leider nicht anders, weil ich mich f&#252;r eine generische (concept-artige) Form des Execution-context entschieden habe; eine virtuelle Methode kann selber kein Template sein, und andererseits m&#246;chte ich den Activity-Record selber template-frei halten
+    </p>
+  </body>
+</html></richcontent>
+<icon BUILTIN="messagebox_warning"/>
+</node>
 </node>
 <node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1689205029658" ID="ID_1144318045" MODIFIED="1689205033146" TEXT="Verifikationen">
 <icon BUILTIN="flag-yellow"/>
+<node BACKGROUND_COLOR="#f0d5c5" COLOR="#990033" CREATED="1690899802680" ID="ID_383665548" MODIFIED="1690899840591" TEXT="Problem: zweifelsfreie Verifikation im Log">
+<icon BUILTIN="messagebox_warning"/>
+<node BACKGROUND_COLOR="#e0ceaa" COLOR="#690f14" CREATED="1690899845778" ID="ID_527585169" MODIFIED="1690899886750" TEXT="mu&#xdf; fehl-Matches vermeiden">
+<icon BUILTIN="clanbomber"/>
+</node>
+<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1690899868436" ID="ID_1034519064" MODIFIED="1690899890797" TEXT="Log sollte idealerweise komplett verifizierbar sein">
+<icon BUILTIN="yes"/>
+</node>
+<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1690899789651" ID="ID_495093897" MODIFIED="1690899844507" TEXT="eine Sequenz-Nummer einf&#xfc;hren">
+<icon BUILTIN="idea"/>
+<node CREATED="1690899895228" ID="ID_689471700" MODIFIED="1690899900231" TEXT="an die Instanz gebunden"/>
+<node CREATED="1690899900699" ID="ID_1842080361" MODIFIED="1690899905547" TEXT="damit 100% reproduzierbar"/>
+<node CREATED="1690899906154" ID="ID_350339048" MODIFIED="1690899917269" TEXT="impliziert eine Aufruf-Sequenz"/>
+<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1690900159528" ID="ID_689193567" MODIFIED="1690900179719" TEXT="Wrapper-Typ verwenden (keinen primitiven Typ)">
+<icon BUILTIN="flag-yellow"/>
+</node>
+<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1690899920322" ID="ID_67461983" MODIFIED="1690899953072" TEXT="den Einzel-Aufruf mit der Nummer einklammern">
+<icon BUILTIN="idea"/>
+</node>
+</node>
+</node>
+<node CREATED="1690899978840" ID="ID_70827658" MODIFIED="1690899987515" TEXT="einen Funktionsaufruf verifizieren">
+<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1690900023906" ID="ID_1470650457" MODIFIED="1690918796008" TEXT="markSequence()">
+<icon BUILTIN="flag-yellow"/>
+</node>
+<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1690900069493" ID="ID_917256156" MODIFIED="1690900150148" TEXT="verifyInvocation(fun, Seq(i), args...)">
+<icon BUILTIN="flag-yellow"/>
+</node>
+</node>
 </node>
 </node>
 <node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1689205081622" ID="ID_1440811513" MODIFIED="1689205086027" TEXT="Me&#xdf;punkte">