diff --git a/src/lib/text-template.hpp b/src/lib/text-template.hpp
index bfdc40ca2..e50abe568 100644
--- a/src/lib/text-template.hpp
+++ b/src/lib/text-template.hpp
@@ -186,11 +186,15 @@ namespace lib {
                                   if ("for" == mat[4])
                                     tag.syntax = mat[3].matched? TagSyntax::END_FOR : TagSyntax::FOR;
                                   else
-                                    throw error::Logic(_Fmt{"unexpected keyword \"%s\""} % mat[4]);
+                                    throw error::Logic{_Fmt{"unexpected keyword \"%s\""} % mat[4]};
                                 }
                               else
                               if (mat[2].matched)
                                 tag.syntax = TagSyntax::ELSE;
+                              else
+                              if ("end" == mat[5])
+                                throw error::Invalid{_Fmt{"unqualified \"end\" without logic-keyword:"
+                                                          " ...%s${end |↯|}"} % tag.lead};
                               else
                                 tag.syntax = TagSyntax::KEYID;
                             }
@@ -358,6 +362,13 @@ namespace lib {
           auto abbrev      = [&](auto s){ return s.length()<16? s : s.substr(s.length()-15); };              // (shorten lead display to 15 chars)
           
            //  Syntax / consistency checks...
+          auto __requireKey    = [&](string descr)
+                                      {
+                                        if (isnil (parseIter->key))
+                                          throw error::Invalid{_Fmt{"Tag without key: ...%s${%s |↯|}"}
+                                                                   % abbrev(lead()) % descr
+                                                              };
+                                      };
           auto __checkBalanced = [&](Clause c)
                                       {
                                         if (not scopeMatch(c))
@@ -400,10 +411,12 @@ namespace lib {
               addLead();
               break;
             case TagSyntax::KEYID:
+              __requireKey("<placeholder>");
               addLead();
               addCode(KEY);
               break;
             case TagSyntax::IF:
+              __requireKey("if <conditional>");
               addLead();
               openScope(IF);
               addCode(COND);
@@ -418,6 +431,7 @@ namespace lib {
               closeScope();
               break;
             case TagSyntax::FOR:
+              __requireKey("for <data-id>");
               addLead();
               openScope(FOR);
               addCode(ITER);
diff --git a/tests/library/text-template-test.cpp b/tests/library/text-template-test.cpp
index 3078e0732..8bf8302c4 100644
--- a/tests/library/text-template-test.cpp
+++ b/tests/library/text-template-test.cpp
@@ -317,6 +317,38 @@ for} tail...
           CHECK (actions[24].code == TextTemplate::Code::TEXT);                // a final static segment after the last active tag
           CHECK (actions[24].val  == " tail...\n"_expect);
           CHECK (actions[24].refIDX == 0);
+          
+          
+          
+          VERIFY_FAIL ("TextTemplate spec without active placeholders"
+                      , TextTemplate::compile("horror boredom"));
+          
+          VERIFY_FAIL ("Tag without key: ...horror ${<placeholder> |↯|}"
+                      , TextTemplate::compile("horror ${ } vacui"));
+          
+          VERIFY_FAIL (" ...horror ${if <conditional> |↯|}"
+                      , TextTemplate::compile("horror ${if} late"));
+          
+          VERIFY_FAIL (" ...horror ${for <data-id> |↯|}"
+                      , TextTemplate::compile("horror ${for} all"));
+          
+          VERIFY_FAIL ("Misplaced ...horror |↯|${else}"
+                      , TextTemplate::compile("horror ${else} deaf"));
+          
+          VERIFY_FAIL ("unqualified \"end\" without logic-keyword"
+                      , TextTemplate::compile("horror without ${end}"));
+          
+          VERIFY_FAIL ("Unbalanced Logic: expect ${end ?? } -- found ...horror ${end |↯|for }"
+                      , TextTemplate::compile("horror ${end for} ever"));
+          
+          VERIFY_FAIL ("Unbalanced Logic: expect ${end for free} -- found ...${end |↯|if }"
+                      , TextTemplate::compile("horror ${for free}${end if}"));
+          
+          VERIFY_FAIL ("Unbalanced Logic: expect ${end for free} -- found ... yet ${end |↯|for me}"
+                      , TextTemplate::compile("${if wee} horror ${for free} yet ${end for me}"));
+          
+          VERIFY_FAIL ("Conflicting ... precipitous ${else} ⟷ ... callous |↯|${else}"
+                      , TextTemplate::compile("${if smarmy} precipitous ${else} callous ${else} horror"));
         }
       
       
diff --git a/wiki/thinkPad.ichthyo.mm b/wiki/thinkPad.ichthyo.mm
index 0809d0e1b..25263a6d2 100644
--- a/wiki/thinkPad.ichthyo.mm
+++ b/wiki/thinkPad.ichthyo.mm
@@ -113257,16 +113257,16 @@ std::cout &lt;&lt; tmpl.render({&quot;what&quot;, &quot;World&quot;}) &lt;&lt; s
 <icon BUILTIN="idea"/>
 </node>
 </node>
-<node BACKGROUND_COLOR="#fdfdcf" COLOR="#ff0000" CREATED="1711237221184" ID="ID_838370074" MODIFIED="1711237227436" TEXT="Fehlerbehandlung">
-<icon BUILTIN="flag-pink"/>
+<node COLOR="#338800" CREATED="1711237221184" ID="ID_838370074" LINK="#ID_428622943" MODIFIED="1711322816722" TEXT="Fehlerbehandlung">
+<icon BUILTIN="button_ok"/>
 <node COLOR="#338800" CREATED="1711237228696" ID="ID_1920021000" MODIFIED="1711312079978" TEXT="unbalancierte Konstrukte">
 <icon BUILTIN="button_ok"/>
 </node>
-<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1711237235134" ID="ID_889276068" MODIFIED="1711237271250" TEXT="komplett leere Tags">
-<icon BUILTIN="flag-yellow"/>
+<node COLOR="#338800" CREATED="1711237235134" ID="ID_889276068" MODIFIED="1711322735840" TEXT="komplett leere Tags">
+<icon BUILTIN="button_ok"/>
 </node>
-<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1711237256363" ID="ID_522815331" MODIFIED="1711237271251" TEXT="fehlender Logic-Key">
-<icon BUILTIN="flag-yellow"/>
+<node COLOR="#338800" CREATED="1711237256363" ID="ID_522815331" MODIFIED="1711322801168" TEXT="fehlender Logic-Key">
+<icon BUILTIN="button_ok"/>
 </node>
 </node>
 </node>
@@ -113392,11 +113392,11 @@ std::cout &lt;&lt; tmpl.render({&quot;what&quot;, &quot;World&quot;}) &lt;&lt; s
 </node>
 <node BACKGROUND_COLOR="#eef0c5" COLOR="#990000" CREATED="1710793091784" ID="ID_1970381008" MODIFIED="1710811906348" TEXT="TextTemplate_test">
 <icon BUILTIN="pencil"/>
-<node BACKGROUND_COLOR="#d2beaf" COLOR="#5c4d6e" CREATED="1710793387393" ID="ID_413372443" MODIFIED="1710811903746" TEXT="simpeUsage">
-<icon BUILTIN="hourglass"/>
+<node COLOR="#338800" CREATED="1710793387393" ID="ID_413372443" MODIFIED="1711322713365" TEXT="simpeUsage">
+<icon BUILTIN="button_ok"/>
 </node>
-<node BACKGROUND_COLOR="#eef0c5" COLOR="#990000" CREATED="1711237120869" ID="ID_1535361808" MODIFIED="1711237133639" TEXT="verify_parsing">
-<icon BUILTIN="pencil"/>
+<node COLOR="#338800" CREATED="1711237120869" ID="ID_1535361808" MODIFIED="1711322709119" TEXT="verify_parsing">
+<icon BUILTIN="button_ok"/>
 <node COLOR="#338800" CREATED="1711237141859" ID="ID_798155590" MODIFIED="1711237176132" TEXT="Basis-Syntax">
 <icon BUILTIN="button_ok"/>
 </node>
@@ -113406,8 +113406,10 @@ std::cout &lt;&lt; tmpl.render({&quot;what&quot;, &quot;World&quot;}) &lt;&lt; s
 <node COLOR="#338800" CREATED="1711237159112" ID="ID_292718692" MODIFIED="1711312317352" TEXT="Compilation in Action-Sequenz">
 <icon BUILTIN="button_ok"/>
 </node>
-<node BACKGROUND_COLOR="#fdfdcf" COLOR="#ff0000" CREATED="1711237177758" ID="ID_428622943" MODIFIED="1711237184293" TEXT="Parse-Fehler">
-<icon BUILTIN="flag-pink"/>
+<node COLOR="#338800" CREATED="1711237177758" ID="ID_428622943" MODIFIED="1711322702127" TEXT="Parse-Fehler">
+<icon BUILTIN="button_ok"/>
+<node COLOR="#435e98" CREATED="1711322819257" ID="ID_566053113" MODIFIED="1711322849606" TEXT="habe mal F&#xe4;lle f&#xfc;r alle bekannten Exceptions konstruiert"/>
+<node COLOR="#435e98" CREATED="1711322831209" ID="ID_1835045684" MODIFIED="1711322849605" TEXT="auch f&#xfc;r leere Tags"/>
 </node>
 </node>
 <node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1710793507744" ID="ID_1535977723" MODIFIED="1710793518661" TEXT="verify_instantiation">