diff --git a/CHANGELOG.md b/CHANGELOG.md
index 56c971afd14..2b4b3f53611 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,8 @@ Docs: https://docs.openclaw.ai
 
 ### Changes
 
+- Agents/Subagents: add an accepted response note for `sessions_spawn` explaining polling subagents are disabled for one-off calls.
+- Agents/Subagents: prefix spawned subagent task messages with context to preserve source information in downstream handling.
 - iOS/Talk: add a `Background Listening` toggle that keeps Talk Mode active while the app is backgrounded (off by default for battery safety). Thanks @zeulewan.
 - iOS/Talk: harden barge-in behavior by disabling interrupt-on-speech when output route is built-in speaker/receiver, reducing false interruptions from local TTS bleed-through. Thanks @zeulewan.
 - iOS/Talk: add a `Voice Directive Hint` toggle for Talk Mode prompts so users can disable ElevenLabs voice-switching instructions to save tokens when not needed. (#18250) Thanks @zeulewan.
diff --git a/src/agents/openclaw-tools.subagents.sessions-spawn.model.e2e.test.ts b/src/agents/openclaw-tools.subagents.sessions-spawn.model.e2e.test.ts
index 2b9df1b5a1c..e81719c5720 100644
--- a/src/agents/openclaw-tools.subagents.sessions-spawn.model.e2e.test.ts
+++ b/src/agents/openclaw-tools.subagents.sessions-spawn.model.e2e.test.ts
@@ -83,6 +83,7 @@ describe("openclaw-tools: subagents (sessions_spawn model + thinking)", () => {
     });
     expect(result.details).toMatchObject({
       status: "accepted",
+      note: "auto-announces on completion, do not poll",
       modelApplied: true,
     });
 
diff --git a/src/agents/subagent-spawn.ts b/src/agents/subagent-spawn.ts
index 189347de9d1..79f802dfeff 100644
--- a/src/agents/subagent-spawn.ts
+++ b/src/agents/subagent-spawn.ts
@@ -39,10 +39,13 @@ export type SpawnSubagentContext = {
   requesterAgentIdOverride?: string;
 };
 
+export const SUBAGENT_SPAWN_ACCEPTED_NOTE = "auto-announces on completion, do not poll";
+
 export type SpawnSubagentResult = {
   status: "accepted" | "forbidden" | "error";
   childSessionKey?: string;
   runId?: string;
+  note?: string;
   modelApplied?: boolean;
   warning?: string;
   error?: string;
@@ -258,6 +261,10 @@ export async function spawnSubagentDirect(
     childDepth,
     maxSpawnDepth,
   });
+  const childTaskMessage = [
+    `[Subagent Context] You are running as a subagent (depth ${childDepth}/${maxSpawnDepth}). Results auto-announce to your requester; do not busy-poll for status.`,
+    `[Subagent Task]: ${task}`,
+  ].join("\n\n");
 
   const childIdem = crypto.randomUUID();
   let childRunId: string = childIdem;
@@ -265,7 +272,7 @@ export async function spawnSubagentDirect(
     const response = await callGateway<{ runId: string }>({
       method: "agent",
       params: {
-        message: task,
+        message: childTaskMessage,
         sessionKey: childSessionKey,
         channel: requesterOrigin?.channel,
         to: requesterOrigin?.to ?? undefined,
@@ -316,6 +323,7 @@ export async function spawnSubagentDirect(
     status: "accepted",
     childSessionKey,
     runId: childRunId,
+    note: SUBAGENT_SPAWN_ACCEPTED_NOTE,
     modelApplied: resolvedModel ? modelApplied : undefined,
     warning: modelWarning,
   };