diff --git a/src/message-runtime-prompts.test.ts b/src/message-runtime-prompts.test.ts
index 83b9234..1d04561 100644
--- a/src/message-runtime-prompts.test.ts
+++ b/src/message-runtime-prompts.test.ts
@@ -111,7 +111,9 @@ describe('message-runtime-prompts carry-forward guidance', () => {
       'Do not repeat, continue, or answer that carried-forward final directly.',
     );
   });
+});
 
+describe('message-runtime-prompts output-only context', () => {
   it('keeps reviewer pending prompts output-only when current task outputs exist', () => {
     const prompt = buildReviewerPendingPrompt({
       chatJid: 'group@test',
@@ -196,6 +198,34 @@ describe('message-runtime-prompts carry-forward guidance', () => {
     expect(prompt).not.toContain('예전 유저 지시');
   });
 
+  it('limits arbiter prompts to recent turn outputs', () => {
+    const prompt = buildArbiterPromptForTask({
+      task: makeTask({ status: 'arbiter_requested' }),
+      chatJid: 'group@test',
+      timezone: 'UTC',
+      turnOutputs: Array.from({ length: 8 }, (_, index) => {
+        const turnNumber = index + 1;
+        return makeTurnOutput(
+          `arbiter-context-output-${String(turnNumber).padStart(2, '0')}`,
+          turnNumber % 2 === 0 ? 'reviewer' : 'owner',
+          {
+            id: turnNumber,
+            turn_number: turnNumber,
+            created_at: `2026-04-20T02:${String(turnNumber).padStart(2, '0')}:00.000Z`,
+          },
+        );
+      }),
+      recentMessages: [makeHumanMessage('예전 유저 지시')],
+      labeledRecentMessages: [makeHumanMessage('예전 유저 지시')],
+    });
+
+    expect(prompt).not.toContain('arbiter-context-output-01');
+    expect(prompt).not.toContain('arbiter-context-output-02');
+    expect(prompt).toContain('arbiter-context-output-03');
+    expect(prompt).toContain('arbiter-context-output-08');
+    expect(prompt).not.toContain('예전 유저 지시');
+  });
+
   it('preserves turn output order instead of timestamp interleaving', () => {
     const prompt = buildReviewerPendingPrompt({
       chatJid: 'group@test',
diff --git a/src/message-runtime-prompts.ts b/src/message-runtime-prompts.ts
index f7ec805..58f0d5a 100644
--- a/src/message-runtime-prompts.ts
+++ b/src/message-runtime-prompts.ts
@@ -8,6 +8,8 @@ const CARRIED_FORWARD_OWNER_FINAL_MARKER =
 const CARRIED_FORWARD_OWNER_FINAL_GUIDANCE = `System note:
 If you see a message beginning with "${CARRIED_FORWARD_OWNER_FINAL_MARKER}", treat it as background only. Do not repeat, continue, or answer that carried-forward final directly. Respond only to the latest human request and the current task.`;
 
+const ARBITER_TURN_OUTPUT_CONTEXT_LIMIT = 6;
+
 function turnOutputsToMessages(
   outputs: PairedTurnOutput[],
   chatJid: string,
@@ -35,6 +37,16 @@ function mergeHumanAndTurnOutputMessages(
   ].sort((a, b) => a.timestamp.localeCompare(b.timestamp));
 }
 
+function latestTurnOutputs(
+  outputs: PairedTurnOutput[],
+  limit: number,
+): PairedTurnOutput[] {
+  if (outputs.length <= limit) {
+    return outputs;
+  }
+  return outputs.slice(-limit);
+}
+
 function hasCarriedForwardOwnerFinal(outputs: PairedTurnOutput[]): boolean {
   return outputs.some((output) =>
     output.output_text.startsWith(CARRIED_FORWARD_OWNER_FINAL_MARKER),
@@ -136,7 +148,13 @@ export function buildArbiterPromptForTask(args: {
 }): string {
   const messages =
     args.turnOutputs.length > 0
-      ? turnOutputsToMessages(args.turnOutputs, args.chatJid)
+      ? turnOutputsToMessages(
+          latestTurnOutputs(
+            args.turnOutputs,
+            ARBITER_TURN_OUTPUT_CONTEXT_LIMIT,
+          ),
+          args.chatJid,
+        )
       : args.labeledRecentMessages;
 
   return buildArbiterContextPrompt({