diff --git a/src/V3AstNodeOther.h b/src/V3AstNodeOther.h
index 36913ebd4..ff391ef43 100644
--- a/src/V3AstNodeOther.h
+++ b/src/V3AstNodeOther.h
@@ -1863,6 +1863,7 @@ class AstVar final : public AstNode {
     bool m_substConstOnly : 1;  // Only substitute if constant
     bool m_overridenParam : 1;  // Overridden parameter by #(...) or defparam
     bool m_trace : 1;  // Trace this variable
+    bool m_isHookInserted : 1;  // This variable is instrumented for coverage
     bool m_isLatched : 1;  // Not assigned in all control paths of combo always
     bool m_isForceable : 1;  // May be forced/released externally from user C code
     bool m_isForcedByCode : 1;  // May be forced/released from AstAssignForce/AstRelease
@@ -1913,6 +1914,7 @@ class AstVar final : public AstNode {
         m_substConstOnly = false;
         m_overridenParam = false;
         m_trace = false;
+        m_isHookInserted = false;
         m_isLatched = false;
         m_isForceable = false;
         m_isForcedByCode = false;
@@ -2055,6 +2057,8 @@ public:
     bool gotNansiType() { return m_gotNansiType; }
     void hasStrengthAssignment(bool flag) { m_hasStrengthAssignment = flag; }
     bool hasStrengthAssignment() { return m_hasStrengthAssignment; }
+    void hasHookInserted(bool flag) { m_isHookInserted = flag; }
+    bool isHookInserted() const { return m_isHookInserted; }
     void isDpiOpenArray(bool flag) { m_isDpiOpenArray = flag; }
     bool isDpiOpenArray() const VL_MT_SAFE { return m_isDpiOpenArray; }
     bool isHideLocal() const { return m_isHideLocal; }
diff --git a/src/V3AstNodes.cpp b/src/V3AstNodes.cpp
index d7ed985dc..a66b0298c 100644
--- a/src/V3AstNodes.cpp
+++ b/src/V3AstNodes.cpp
@@ -2790,6 +2790,8 @@ void AstVar::dumpJson(std::ostream& str) const {
     dumpJsonBoolFunc(str, attrSFormat);
     dumpJsonBoolFunc(str, ignorePostWrite);
     dumpJsonBoolFunc(str, ignoreSchedWrite);
+    dumpJsonBoolFunc(str, isHookInserted);
+    dumpJsonNum(str, "width", width());
     dumpJsonGen(str);
 }
 void AstScope::dump(std::ostream& str) const {
diff --git a/src/V3InsertHook.cpp b/src/V3InsertHook.cpp
index c027ea13c..9183db557 100644
--- a/src/V3InsertHook.cpp
+++ b/src/V3InsertHook.cpp
@@ -441,6 +441,7 @@ class HookInsTargetFndr final : public VNVisitor {
                     AstVar* varp = nodep->cloneTree(false);
                     varp->name("tmp_" + nodep->name());
                     varp->origName("tmp_" + nodep->name());
+                    varp->hasHookInserted(true);
                     varp->trace(true);
                     if (varp->varType() == VVarType::WIRE) { varp->varType(VVarType::VAR); }
                     setVar(nodep, varp, m_target);