diff --git a/experiments/shell/shell.cpp b/experiments/shell/shell.cpp
index 06396a2c..b93151c1 100644
--- a/experiments/shell/shell.cpp
+++ b/experiments/shell/shell.cpp
@@ -46,7 +46,7 @@ void selection_discard_diagnostic(const char* reason, size_t row) {
     std::ofstream stream(path, std::ios::app);
     if (!stream) return;
     stream << "{\"schema\":\"termforge-selection-discard-v1\",\"reason\":\"" << reason
-           << "\",\"row\":" << row << "}\n";
+           << "\",\"row\":" << row << ",\"t_ms\":" << GetTickCount64() << "}\n";
 }
 void install_selection_diagnostic_once() {
     static std::once_flag once;
diff --git a/experiments/shell/workspace_actions_scenario.hpp b/experiments/shell/workspace_actions_scenario.hpp
index b046f297..dd86de95 100644
--- a/experiments/shell/workspace_actions_scenario.hpp
+++ b/experiments/shell/workspace_actions_scenario.hpp
@@ -169,7 +169,7 @@ inline void Workspace::scenario_actions() {
                 <<",\"status\":"; termforge::Screen::quoted(out,utf8(target->status_text().c_str()));
             out<<",\"frame_matches_full\":"<<(target->frame_matches_full()?"true":"false")<<'}';
         }
-        out<<"]}"; geometry_samples_.push_back(out.str());
+        out<<"]"; out<<",\"t_ms\":"<<GetTickCount64()<<'}'; geometry_samples_.push_back(out.str());
         std::ofstream journal(directory/"actions-progress.jsonl",std::ios::binary|std::ios::app); journal<<out.str()<<'\n'; journal.close(); require(journal.good(),"actions progress write failed");
         if(std::string_view(phase).rfind("geometry-",0)==0) {
             Bitmap frame(parent.right,parent.bottom); paint(frame.dc);