From 1c3b280c6a0e21cce6f21264d0087a7f8d9ff14b Mon Sep 17 00:00:00 2001
From: claude-code-best <claude-code-best@proton.me>
Date: Sat, 25 Apr 2026 14:31:32 +0800
Subject: [PATCH] =?UTF-8?q?fix:=20=E5=B0=9D=E8=AF=95=E4=BF=AE=E5=A4=8D?=
 =?UTF-8?q?=E5=A4=9A=E8=BD=AE=E5=AF=B9=E8=AF=9D=E7=BC=93=E5=AD=98=E5=A4=B1?=
 =?UTF-8?q?=E6=95=88=20skill=20=E6=8F=90=E5=8D=87=E7=9A=84=E9=97=AE?=
 =?UTF-8?q?=E9=A2=98?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/utils/attachments.ts          | 17 +++++++++++++++++
 src/utils/conversationRecovery.ts | 12 +++++++++++-
 2 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/src/utils/attachments.ts b/src/utils/attachments.ts
index 4085c42b9..7eb449474 100644
--- a/src/utils/attachments.ts
+++ b/src/utils/attachments.ts
@@ -819,6 +819,10 @@ export async function getAttachments(
         !options?.skipSkillDiscovery
           ? [
               maybe('skill_discovery', async () => {
+                if (suppressNextDiscovery) {
+                  suppressNextDiscovery = false
+                  return []
+                }
                 const result = await skillSearchModules.prefetch.getTurnZeroSkillDiscovery(
                   input,
                   messages ?? [],
@@ -2638,6 +2642,7 @@ const sentSkillNames = new Map<string, Set<string>>()
 export function resetSentSkillNames(): void {
   sentSkillNames.clear()
   suppressNext = false
+  suppressNextDiscovery = false
 }
 
 /**
@@ -2661,6 +2666,18 @@ export function suppressNextSkillListing(): void {
 }
 let suppressNext = false
 
+/**
+ * Suppress the next skill-discovery injection on resume. Same rationale as
+ * suppressNextSkillListing: skill_discovery attachments are not persisted to
+ * transcript for non-ant users, so the prior process's discovery result is
+ * already in the conversation history the model sees. Re-generating it would
+ * inject duplicate content and bust the prompt cache prefix.
+ */
+export function suppressNextSkillDiscovery(): void {
+  suppressNextDiscovery = true
+}
+let suppressNextDiscovery = false
+
 // When skill-search is enabled and the filtered (bundled + MCP) listing exceeds
 // this count, fall back to bundled-only. Protects MCP-heavy users (100+ servers)
 // from truncation while keeping the turn-0 guarantee for typical setups.
diff --git a/src/utils/conversationRecovery.ts b/src/utils/conversationRecovery.ts
index 51c36520c..3379e9dd0 100644
--- a/src/utils/conversationRecovery.ts
+++ b/src/utils/conversationRecovery.ts
@@ -18,7 +18,7 @@ import type {
   NormalizedUserMessage,
 } from '../types/message.js'
 import { PERMISSION_MODES } from '../types/permissions.js'
-import { suppressNextSkillListing } from './attachments.js'
+import { suppressNextSkillDiscovery, suppressNextSkillListing } from './attachments.js'
 import {
   copyFileHistoryForResume,
   type FileHistorySnapshot,
@@ -403,6 +403,16 @@ export function restoreSkillStateFromMessages(messages: Message[]): void {
       suppressNextSkillListing()
     }
   }
+
+  // Unconditionally suppress skill_listing and skill_discovery on resume.
+  // Attachments are not persisted to transcript for non-ant users
+  // (isLoggableMessage filters them out), so the per-type checks above may
+  // never find them even though the prior process already injected the content
+  // into the conversation via <system-reminder> blocks. Without this, every
+  // resume re-injects ~1K tokens of duplicate content and busts the Anthropic
+  // prompt cache prefix (which requires 100% byte-identical segments).
+  suppressNextSkillListing()
+  suppressNextSkillDiscovery()
 }
 
 /**