chore(core): remove sub-goals feature from LLM planning (#1975)

* refactor(core): rename includeSubGoals to deepThink and remove sub-goal logic from planning prompt

The model no longer needs to do task decomposition (sub-goals). This
removes all goal/subGoal related logic from the planning prompt and its
caller, keeping only the simpler instruction-based flow.

https://claude.ai/code/session_016KXax4JyZu2MKkA2XjRX6t

* fix(core): restore detailed thought tag guidance (without sub-goal references)

Keep the full thought description telling the model what to consider
(user's requirement, current state, next action) - just without the
sub-goal related parts.

https://claude.ai/code/session_016KXax4JyZu2MKkA2XjRX6t

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: yuyutaotao

packages/core/src/ai-model/llm-planning.ts

@@ -18,11 +18,7 @@ import {
 } from '../common';
 import type { ConversationHistory } from './conversation-history';
 import { systemPromptToTaskPlanning } from './prompt/llm-planning';
-import {
-  extractXMLTag,
-  parseMarkFinishedIndexes,
-  parseSubGoalsFromXML,
-} from './prompt/util';
+import { extractXMLTag } from './prompt/util';
 import {
   AIResponseParseError,
   callAI,
@@ -58,17 +54,6 @@ export function parseXMLPlanningResponse(
     finalizeMessage = completeGoalMatch[2]?.trim() || undefined;
   }
 
-  // Parse sub-goal related tags
-  const updatePlanContent = extractXMLTag(xmlString, 'update-plan-content');
-  const markSubGoalDone = extractXMLTag(xmlString, 'mark-sub-goal-done');
-
-  const updateSubGoals = updatePlanContent
-    ? parseSubGoalsFromXML(updatePlanContent)
-    : undefined;
-  const markFinishedIndexes = markSubGoalDone
-    ? parseMarkFinishedIndexes(markSubGoalDone)
-    : undefined;
-
   // Parse action
   let action: any = null;
   if (actionType && actionType.toLowerCase() !== 'null') {
@@ -98,8 +83,6 @@ export function parseXMLPlanningResponse(
     action,
     ...(finalizeMessage !== undefined ? { finalizeMessage } : {}),
     ...(finalizeSuccess !== undefined ? { finalizeSuccess } : {}),
-    ...(updateSubGoals?.length ? { updateSubGoals } : {}),
-    ...(markFinishedIndexes?.length ? { markFinishedIndexes } : {}),
   };
 }
 
@@ -123,15 +106,12 @@ export async function plan(
 
   const { modelFamily } = modelConfig;
 
-  // Only enable sub-goals when deepThink is true
-  const includeSubGoals = opts.deepThink === true;
-
   const systemPrompt = await systemPromptToTaskPlanning({
     actionSpace: opts.actionSpace,
     modelFamily,
     includeBbox: opts.includeBbox,
     includeThought: true, // always include thought
-    includeSubGoals,
+    deepThink: opts.deepThink === true,
   });
 
   let imagePayload = screenshotBase64;
@@ -166,13 +146,11 @@ export async function plan(
 
   let latestFeedbackMessage: ChatCompletionMessageParam;
 
-  // Build sub-goal status text to include in the message
-  // In deepThink mode: show full sub-goals with logs
-  // In non-deepThink mode: show historical execution logs
-  const subGoalsText = includeSubGoals
-    ? conversationHistory.subGoalsToText()
-    : conversationHistory.historicalLogsToText();
-  const subGoalsSection = subGoalsText ? `\n\n${subGoalsText}` : '';
+  // Build historical execution logs text to include in the message
+  const historicalLogsText = conversationHistory.historicalLogsToText();
+  const historicalLogsSection = historicalLogsText
+    ? `\n\n${historicalLogsText}`
+    : '';
 
   // Build memories text to include in the message
   const memoriesText = conversationHistory.memoriesToText();
@@ -184,7 +162,7 @@ export async function plan(
       content: [
         {
           type: 'text',
-          text: `${conversationHistory.pendingFeedbackMessage}. The previous action has been executed, here is the latest screenshot. Please continue according to the instruction.${memoriesSection}${subGoalsSection}`,
+          text: `${conversationHistory.pendingFeedbackMessage}. The previous action has been executed, here is the latest screenshot. Please continue according to the instruction.${memoriesSection}${historicalLogsSection}`,
         },
         {
           type: 'image_url',
@@ -203,7 +181,7 @@ export async function plan(
       content: [
         {
           type: 'text',
-          text: `this is the latest screenshot${memoriesSection}${subGoalsSection}`,
+          text: `this is the latest screenshot${memoriesSection}${historicalLogsSection}`,
         },
         {
           type: 'image_url',
@@ -256,10 +234,6 @@ export async function plan(
     if (planFromAI.finalizeSuccess !== undefined) {
       debug('task completed via <complete> tag, stop planning');
       shouldContinuePlanning = false;
-      // Mark all sub-goals as finished when goal is completed (only when deepThink is enabled)
-      if (includeSubGoals) {
-        conversationHistory.markAllSubGoalsFinished();
-      }
     }
 
     const returnValue: PlanningAIResponse = {
@@ -301,25 +275,9 @@ export async function plan(
       });
     });
 
-    // Update sub-goals in conversation history based on response (only when deepThink is enabled)
-    if (includeSubGoals) {
-      if (planFromAI.updateSubGoals?.length) {
-        conversationHistory.setSubGoals(planFromAI.updateSubGoals);
-      }
-      if (planFromAI.markFinishedIndexes?.length) {
-        for (const index of planFromAI.markFinishedIndexes) {
-          conversationHistory.markSubGoalFinished(index);
-        }
-      }
-      // Append the planning log to the currently running sub-goal
-      if (planFromAI.log) {
-        conversationHistory.appendSubGoalLog(planFromAI.log);
-      }
-    } else {
-      // In non-deepThink mode, accumulate logs as historical execution steps
-      if (planFromAI.log) {
-        conversationHistory.appendHistoricalLog(planFromAI.log);
-      }
+    // Accumulate logs as historical execution steps
+    if (planFromAI.log) {
+      conversationHistory.appendHistoricalLog(planFromAI.log);
     }
 
     // Append memory to conversation history if present