diff --git a/apps/api/scripts/e2e_tool_call_verification.py b/apps/api/scripts/e2e_tool_call_verification.py
index b0dd20c7f..6bd025c9e 100644
--- a/apps/api/scripts/e2e_tool_call_verification.py
+++ b/apps/api/scripts/e2e_tool_call_verification.py
@@ -221,9 +221,10 @@ class E2EVerification:
             headers = {"Content-Type": "application/json"}
 
             # 如果有 HMAC Secret，計算簽名
+            # 2026-03-29 Claude Code: 修正 Header 名稱為 X-Signature-256 (與 API 一致)
             if HMAC_SECRET:
                 signature = compute_hmac_signature(HMAC_SECRET, payload_bytes)
-                headers["X-Webhook-Signature"] = signature
+                headers["X-Signature-256"] = signature
                 print_info("HMAC", f"已簽名 ({signature[:20]}...)")
             else:
                 print_warn("無 HMAC Secret - 僅限測試環境")