From 3c5e68e80faef28971d9e4f22d26dc5b0879ac7a Mon Sep 17 00:00:00 2001
From: Moeed Ahmed <moeedahmed@Moeed-Mac-mini.local>
Date: Sat, 9 May 2026 15:08:47 +0100
Subject: [PATCH] fix: bound subagent completion context

---
 .../telegram/src/bot-handlers.runtime.ts      |  4 ++--
 src/agents/internal-events.ts                 | 16 ++++++++++++++-
 ...ded-helpers.sanitizeuserfacingtext.test.ts | 20 +++++++++++++++++++
 src/agents/subagent-announce-delivery.test.ts |  1 +
 4 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/extensions/telegram/src/bot-handlers.runtime.ts b/extensions/telegram/src/bot-handlers.runtime.ts
index 92f292a8b14..3a6fdfbff1b 100644
--- a/extensions/telegram/src/bot-handlers.runtime.ts
+++ b/extensions/telegram/src/bot-handlers.runtime.ts
@@ -300,7 +300,7 @@ export const registerTelegramHandlers = ({
         if (!isMultiToggleButton(button) || !isSelectedMultiButton(button)) {
           return [];
         }
-        return [button.callback_data!.slice(`${MULTI_SELECT_PREFIX}toggle|`.length)];
+        return [button.callback_data.slice(`${MULTI_SELECT_PREFIX}toggle|`.length)];
       }),
     );
   const updateMultiSelectKeyboard = (
@@ -313,7 +313,7 @@ export const registerTelegramHandlers = ({
         if (!isMultiToggleButton(button)) {
           return button;
         }
-        const buttonValue = button.callback_data!.slice(`${MULTI_SELECT_PREFIX}toggle|`.length);
+        const buttonValue = button.callback_data.slice(`${MULTI_SELECT_PREFIX}toggle|`.length);
         const baseText = stripMultiSelectPrefix(button.text);
         const selected =
           action === "clear"
diff --git a/src/agents/internal-events.ts b/src/agents/internal-events.ts
index 6ecb489e138..13e60b0237e 100644
--- a/src/agents/internal-events.ts
+++ b/src/agents/internal-events.ts
@@ -25,6 +25,8 @@ type AgentTaskCompletionInternalEvent = {
   replyInstruction: string;
 };
 
+const MAX_CHILD_RESULT_PROMPT_CHARS = 4_000;
+
 export type AgentInternalEvent = AgentTaskCompletionInternalEvent;
 
 export { INTERNAL_RUNTIME_CONTEXT_BEGIN, INTERNAL_RUNTIME_CONTEXT_END };
@@ -41,11 +43,23 @@ function sanitizeMultilineField(value: string, fallback: string): string {
   return sanitized || fallback;
 }
 
+function truncateChildResultForPrompt(value: string): string {
+  if (value.length <= MAX_CHILD_RESULT_PROMPT_CHARS) {
+    return value;
+  }
+  return [
+    value.slice(0, MAX_CHILD_RESULT_PROMPT_CHARS).trimEnd(),
+    "",
+    `[child result truncated: ${value.length - MAX_CHILD_RESULT_PROMPT_CHARS} additional characters omitted]`,
+  ].join("\n");
+}
+
 function formatChildResultDataBlock(value: string): string {
+  const safeValue = truncateChildResultForPrompt(value);
   return (
     wrapPromptDataBlock({
       label: "Child result",
-      text: value,
+      text: safeValue,
     }) || "Child result: (no output)"
   );
 }
diff --git a/src/agents/pi-embedded-helpers.sanitizeuserfacingtext.test.ts b/src/agents/pi-embedded-helpers.sanitizeuserfacingtext.test.ts
index 05236f98f5f..24e4bf822f3 100644
--- a/src/agents/pi-embedded-helpers.sanitizeuserfacingtext.test.ts
+++ b/src/agents/pi-embedded-helpers.sanitizeuserfacingtext.test.ts
@@ -362,6 +362,26 @@ describe("sanitizeUserFacingText", () => {
     );
   });
 
+  it("bounds large child completion results before injecting internal context", () => {
+    const internal = formatAgentInternalEventsForPrompt([
+      {
+        type: "task_completion",
+        source: "subagent",
+        childSessionKey: "agent:main:subagent:test",
+        childSessionId: "sess_1",
+        announceType: "subagent task",
+        taskLabel: "Investigate issue",
+        status: "ok",
+        statusLabel: "completed successfully",
+        result: "x".repeat(6_000),
+        replyInstruction: "Reply to the user in your own words.",
+      },
+    ]);
+
+    expect(internal).toContain("[child result truncated: 2000 additional characters omitted]");
+    expect(internal.length).toBeLessThan(5_000);
+  });
+
   it("does not strip inline delimiter mentions that are not standalone marker lines", () => {
     const input = `Note: ${INTERNAL_RUNTIME_CONTEXT_BEGIN} appears inline and should stay.`;
     expect(sanitizeUserFacingText(input)).toBe(input);
diff --git a/src/agents/subagent-announce-delivery.test.ts b/src/agents/subagent-announce-delivery.test.ts
index 06c22c95295..eac0682a64a 100644
--- a/src/agents/subagent-announce-delivery.test.ts
+++ b/src/agents/subagent-announce-delivery.test.ts
@@ -1237,6 +1237,7 @@ describe("deliverSubagentAnnouncement completion delivery", () => {
           childSessionKey: "agent:openclaw:subagent:child-123",
           childSessionId: "child-123",
           announceType: "subagent task",
+          taskLabel: "channel completion smoke",
           status: "ok",
           statusLabel: "completed successfully",
           result: "Raw child result that should stay internal.",