diff --git a/web/app/components/workflow/run/__tests__/tracing-panel.spec.tsx b/web/app/components/workflow/run/__tests__/tracing-panel.spec.tsx
index 9610d2e4edf..07f7e795671 100644
--- a/web/app/components/workflow/run/__tests__/tracing-panel.spec.tsx
+++ b/web/app/components/workflow/run/__tests__/tracing-panel.spec.tsx
@@ -135,11 +135,23 @@ describe('TracingPanel', () => {
 
     fireEvent.mouseLeave(hoverTarget)
 
-    fireEvent.click(screen.getAllByRole('button')[0]!)
+    const parallelToggle = screen.getByRole('button', {
+      name: 'Parallel Group',
+      expanded: true,
+    })
+    expect(parallelToggle).toHaveAttribute('aria-controls', 'parallel-1-children')
+
+    fireEvent.click(parallelToggle)
+    expect(
+      screen.getByRole('button', { name: 'Parallel Group', expanded: false }),
+    ).toBeInTheDocument()
     expect(
       container.querySelector('[data-parallel-id="parallel-1"] > div:last-child'),
     )!.toHaveClass('hidden')
-    fireEvent.click(screen.getAllByRole('button')[0]!)
+    fireEvent.click(parallelToggle)
+    expect(
+      screen.getByRole('button', { name: 'Parallel Group', expanded: true }),
+    ).toBeInTheDocument()
     expect(
       container.querySelector('[data-parallel-id="parallel-1"] > div:last-child'),
     ).not.toHaveClass('hidden')
diff --git a/web/app/components/workflow/run/tracing-panel.tsx b/web/app/components/workflow/run/tracing-panel.tsx
index 51849851d97..5c28554bd5e 100644
--- a/web/app/components/workflow/run/tracing-panel.tsx
+++ b/web/app/components/workflow/run/tracing-panel.tsx
@@ -90,6 +90,9 @@ const TracingPanel: FC<TracingPanelProps> = ({
           <div className="mb-1 flex items-center">
             <button
               type="button"
+              aria-controls={`${node.id}-children`}
+              aria-expanded={!isCollapsed}
+              aria-label={parallelDetail.parallelTitle}
               onClick={() => toggleCollapse(node.id)}
               className={cn(
                 'mr-2 transition-colors',
@@ -115,7 +118,10 @@ const TracingPanel: FC<TracingPanelProps> = ({
               }}
             ></div>
           </div>
-          <div className={`relative pl-2 ${isCollapsed ? 'hidden' : ''}`}>
+          <div
+            id={`${node.id}-children`}
+            className={`relative pl-2 ${isCollapsed ? 'hidden' : ''}`}
+          >
             <div
               className={cn(
                 'absolute top-0 bottom-0 left-1.25 w-0.5',