diff --git a/src/app/shared/task-execution-viewer/task-execution-viewer.css b/src/app/shared/task-execution-viewer/task-execution-viewer.css
index b896bde..ed5d88f 100644
--- a/src/app/shared/task-execution-viewer/task-execution-viewer.css
+++ b/src/app/shared/task-execution-viewer/task-execution-viewer.css
@@ -95,6 +95,41 @@
   line-height: 20px;
 }
 
+/* The button has to be a positioning context for the badge, and must not clip it. */
+.execution-action-button {
+  position: relative;
+  overflow: visible;
+}
+
+/*
+ * Who answers the flow's human steps - you, or an LLM - is the only difference between the two run
+ * buttons, so both keep the play and the badge carries that difference. It is small on purpose: it
+ * qualifies the play rather than competing with it, and the two sit side by side, which is what
+ * makes either one legible.
+ */
+.execution-action-badge {
+  position: absolute;
+  right: -3px;
+  bottom: -3px;
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  width: 17px;
+  height: 17px;
+  border-radius: 999px;
+  border: 1px solid currentColor;
+  background: #ffffff;
+  color: inherit;
+}
+
+.execution-action-badge mat-icon {
+  font-size: 11px;
+  width: 11px;
+  height: 11px;
+  line-height: 11px;
+  color: #0f172a;
+}
+
 .execution-action-button:disabled {
   opacity: 0.4;
   cursor: not-allowed;
diff --git a/src/app/shared/task-execution-viewer/task-execution-viewer.html b/src/app/shared/task-execution-viewer/task-execution-viewer.html
index 5c25be8..929b15e 100644
--- a/src/app/shared/task-execution-viewer/task-execution-viewer.html
+++ b/src/app/shared/task-execution-viewer/task-execution-viewer.html
@@ -181,7 +181,21 @@
               [disabled]="!canStartExecution() || startInProgress()"
               (click)="startExecution()">
               <mat-icon fontIcon="play_arrow"></mat-icon>
+              <!-- Both run buttons keep the play; the badge carries the one thing that differs. -->
+              <span class="execution-action-badge"><mat-icon fontIcon="person"></mat-icon></span>
             </button>
+            @if (execution()!.simulationAvailable === true) {
+            <button
+              type="button"
+              class="execution-action-button execution-graph-action-button execution-action-button-simulate"
+              matTooltip="Run simulated - an LLM answers the human steps"
+              aria-label="Run simulated - an LLM answers the human steps"
+              [disabled]="!canSimulateExecution()"
+              (click)="simulateExecution()">
+              <mat-icon fontIcon="play_arrow"></mat-icon>
+              <span class="execution-action-badge"><mat-icon fontIcon="smart_toy"></mat-icon></span>
+            </button>
+            }
             <button
               type="button"
               class="execution-action-button execution-graph-action-button execution-action-button-stop"
@@ -200,17 +214,6 @@
               (click)="resumeExecution()">
               <mat-icon fontIcon="restart_alt"></mat-icon>
             </button>
-            @if (execution()!.simulationAvailable === true) {
-            <button
-              type="button"
-              class="execution-action-button execution-graph-action-button execution-action-button-simulate"
-              matTooltip="Simulate execution"
-              aria-label="Simulate execution"
-              [disabled]="!canSimulateExecution()"
-              (click)="simulateExecution()">
-              <mat-icon fontIcon="science"></mat-icon>
-            </button>
-            }
             <button
               type="button"
               class="execution-action-button execution-graph-action-button execution-graph-action-button-bias"
diff --git a/src/app/shared/task-execution-viewer/task-execution-viewer.ts b/src/app/shared/task-execution-viewer/task-execution-viewer.ts
index 274f8b3..d7116ab 100644
--- a/src/app/shared/task-execution-viewer/task-execution-viewer.ts
+++ b/src/app/shared/task-execution-viewer/task-execution-viewer.ts
@@ -699,7 +699,9 @@ export class TaskExecutionViewerComponent implements OnDestroy {
     const gate = this.authorizationGate();
     if (gate.missingProviders.length) return `Missing provider credential: ${gate.missingProviders.join(', ')}`;
     if (gate.runtime.length) return 'Missing provider authorization';
-    return 'Start execution';
+    // Names who answers the flow's human steps, which is the only thing that separates this from
+    // the simulated run beside it - and the part an icon can only gesture at.
+    return 'Run - you answer the human steps';
   });
 
   readonly cancelExecutionTooltip = computed(() =>