diff --git a/packages/opencode/src/cli/cmd/tui/routes/session/index.tsx b/packages/opencode/src/cli/cmd/tui/routes/session/index.tsx
index c04e58acec..b6cde459e9 100644
--- a/packages/opencode/src/cli/cmd/tui/routes/session/index.tsx
+++ b/packages/opencode/src/cli/cmd/tui/routes/session/index.tsx
@@ -2000,7 +2000,8 @@ function Task(props: ToolProps<typeof TaskTool>) {
 
   const content = createMemo(() => {
     if (!props.input.description) return ""
-    let content = [`${Locale.titlecase(props.input.subagent_type ?? "General")} Task — ${props.input.description}`]
+    const description = props.metadata.background === true ? `${props.input.description} (background)` : props.input.description
+    let content = [`${Locale.titlecase(props.input.subagent_type ?? "General")} Task — ${description}`]
 
     if (isRunning() && tools().length > 0) {
       // content[0] += ` · ${tools().length} toolcalls`
diff --git a/packages/ui/src/components/message-part.tsx b/packages/ui/src/components/message-part.tsx
index 9c0c90c000..3694b204fb 100644
--- a/packages/ui/src/components/message-part.tsx
+++ b/packages/ui/src/components/message-part.tsx
@@ -1751,9 +1751,10 @@ ToolRegistry.register({
     const title = createMemo(() => agent().name ?? i18n.t("ui.tool.agent.default"))
     const tone = createMemo(() => agent().color)
     const subtitle = createMemo(() => {
-      const value = props.input.description
-      if (typeof value === "string" && value) return value
-      return childSessionId()
+      const value = typeof props.input.description === "string" && props.input.description ? props.input.description : childSessionId()
+      if (!value) return value
+      if (props.metadata.background === true) return `${value} (background)`
+      return value
     })
     const running = createMemo(() => props.status === "pending" || props.status === "running")