fix: task id passed to background job for continuation (#30485)

packages/opencode/src/tool/task.ts

@@ -10,7 +10,7 @@ import { Agent } from "../agent/agent"
 import { deriveSubagentSessionPermission } from "../agent/subagent-permissions"
 import type { SessionPrompt } from "../session/prompt"
 import { Config } from "@/config/config"
-import { Cause, Effect, Exit, Schema, Scope } from "effect"
+import { Effect, Exit, Schema, Scope } from "effect"
 import { EffectBridge } from "@/effect/bridge"
 import { RuntimeFlags } from "@/effect/runtime-flags"
 import { Database } from "@opencode-ai/core/database/database"
@@ -69,6 +69,17 @@ function backgroundOutput(sessionID: SessionID) {
   ].join("\n")
 }
 
+function backgroundUpdateOutput(sessionID: SessionID) {
+  return [
+    `<task id="${sessionID}" state="running">`,
+    "<summary>Background task updated</summary>",
+    "<task_result>",
+    "Additional context sent to the background task.",
+    "</task_result>",
+    "</task>",
+  ].join("\n")
+}
+
 function backgroundMessage(input: {
   sessionID: SessionID
   description: string
@@ -90,11 +101,6 @@ function backgroundMessage(input: {
   ].join("\n")
 }
 
-function errorText(error: unknown) {
-  if (error instanceof Error) return error.message
-  return String(error)
-}
-
 export const TaskTool = Tool.define(
   id,
   Effect.gen(function* () {
@@ -231,9 +237,16 @@ export const TaskTool = Tool.define(
           .pipe(Effect.ignore, Effect.forkIn(scope, { startImmediately: true }))
       })
 
-      const existing = yield* background.get(nextSession.id)
-      if (existing?.status === "running") {
-        return yield* Effect.fail(new Error(`Task ${nextSession.id} is already running.`))
+      if (yield* background.extend({ id: nextSession.id, run: runTask() })) {
+        return {
+          title: params.description,
+          metadata: {
+            ...metadata,
+            background: true,
+            jobId: nextSession.id,
+          },
+          output: backgroundUpdateOutput(nextSession.id),
+        }
       }
 
       if (runInBackground) {
@@ -242,16 +255,18 @@ export const TaskTool = Tool.define(
           type: id,
           title: params.description,
           metadata,
-          run: runTask().pipe(
-            Effect.tap((text) => inject("completed", text).pipe(Effect.ignore)),
-            Effect.catchCause((cause) =>
-              (Cause.hasInterruptsOnly(cause)
-                ? Effect.void
-                : inject("error", errorText(Cause.squash(cause))).pipe(Effect.ignore)
-              ).pipe(Effect.andThen(Effect.failCause(cause))),
-            ),
-          ),
+          run: runTask(),
         })
+        yield* background
+          .wait({ id: info.id })
+          .pipe(
+            Effect.flatMap((result) => {
+              if (result.info?.status === "completed") return inject("completed", result.info.output ?? "")
+              if (result.info?.status === "error") return inject("error", result.info.error ?? "")
+              return Effect.void
+            }),
+            Effect.forkIn(scope, { startImmediately: true }),
+          )
 
         return {
           title: params.description,