refine background task ux and auto-resume

packages/opencode/src/cli/cmd/tui/routes/session/index.tsx

@@ -1967,11 +1967,7 @@ function Task(props: ToolProps<typeof TaskTool>) {
     return !!msgs().findLast((msg) => msg.role === "assistant")?.error
   })
   const isRunning = createMemo(() => props.part.state.status === "running" || childRunning())
-  const toolLabel = createMemo(() => {
-    const total = counts().all
-    if (!childRunning()) return `${total} toolcalls`
-    return `${counts().done}/${total} toolcalls`
-  })
+  const toolLabel = createMemo(() => `${childRunning() ? counts().done : counts().all} toolcalls`)
 
   return (
     <Switch>
@@ -1989,9 +1985,6 @@ function Task(props: ToolProps<typeof TaskTool>) {
           <box>
             <text style={{ fg: theme.textMuted }}>
               {props.input.description} ({toolLabel()})
-              <Show when={background()}>
-                <span> · background</span>
-              </Show>
             </text>
             <Show when={background()}>
               <text style={{ fg: failed() ? theme.error : backgroundRunning() ? theme.warning : theme.textMuted }}>

packages/opencode/src/tool/task.ts

@@ -6,6 +6,7 @@ import { MessageV2 } from "../session/message-v2"
 import { Identifier } from "../id/id"
 import { Agent } from "../agent/agent"
 import { SessionPrompt } from "../session/prompt"
+import { SessionStatus } from "../session/status"
 import { iife } from "@/util/iife"
 import { defer } from "@/util/defer"
 import { Config } from "../config/config"
@@ -68,6 +69,47 @@ function errorText(error: unknown) {
   return String(error)
 }
 
+function resultTaskID(input: unknown) {
+  if (!input || typeof input !== "object") return
+  const taskID = Reflect.get(input, "task_id")
+  if (typeof taskID === "string") return taskID
+}
+
+function polled(input: { message: MessageV2.WithParts; taskID: string }) {
+  if (input.message.info.role !== "assistant") return false
+  return input.message.parts.some((part) => {
+    if (part.type !== "tool") return false
+    if (part.tool !== "task_status") return false
+    if (part.state.status !== "completed") return false
+    return resultTaskID(part.state.input) === input.taskID
+  })
+}
+
+async function latestUser(sessionID: string) {
+  const [message] = await Session.messages({
+    sessionID,
+    limit: 1,
+  })
+  if (!message) return
+  if (message.info.role !== "user") return
+  return message.info.id
+}
+
+async function continueParent(input: { parentID: string; userID: string; taskID: string }) {
+  const message =
+    SessionStatus.get(input.parentID).type === "idle"
+      ? undefined
+      : await SessionPrompt.loop({
+          sessionID: input.parentID,
+        }).catch(() => undefined)
+  if (message && polled({ message, taskID: input.taskID })) return
+  if (SessionStatus.get(input.parentID).type !== "idle") return
+  if ((await latestUser(input.parentID)) !== input.userID) return
+  await SessionPrompt.loop({
+    sessionID: input.parentID,
+  })
+}
+
 export const TaskTool = Tool.define("task", async (ctx) => {
   const agents = await Agent.list().then((x) => x.filter((a) => a.mode !== "primary"))
 
@@ -210,12 +252,28 @@ export const TaskTool = Tool.define("task", async (ctx) => {
           })
 
         void run()
-          .then((text) => {
-            void inject("completed", text).catch(() => {})
-          })
-          .catch((error) => {
-            void inject("error", errorText(error)).catch(() => {})
-          })
+          .then((text) =>
+            inject("completed", text)
+              .then((message) =>
+                continueParent({
+                  parentID: ctx.sessionID,
+                  userID: message.info.id,
+                  taskID: session.id,
+                }),
+              )
+              .catch(() => {}),
+          )
+          .catch((error) =>
+            inject("error", errorText(error))
+              .then((message) =>
+                continueParent({
+                  parentID: ctx.sessionID,
+                  userID: message.info.id,
+                  taskID: session.id,
+                }),
+              )
+              .catch(() => {}),
+          )
 
         return {
           title: params.description,