From a05a815f99a2e2748dfac93b3c1fe85cd8345e1e Mon Sep 17 00:00:00 2001
From: CaIon <i@caion.me>
Date: Thu, 13 Nov 2025 16:49:40 +0800
Subject: [PATCH] fix(claude): Prevent duplicate header values in WriteHeaders
 method

---
 setting/model_setting/claude.go | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/setting/model_setting/claude.go b/setting/model_setting/claude.go
index 1be0e3e4..aa010c07 100644
--- a/setting/model_setting/claude.go
+++ b/setting/model_setting/claude.go
@@ -50,9 +50,18 @@ func GetClaudeSettings() *ClaudeSettings {
 func (c *ClaudeSettings) WriteHeaders(originModel string, httpHeader *http.Header) {
 	if headers, ok := c.HeadersSettings[originModel]; ok {
 		for headerKey, headerValues := range headers {
-			httpHeader.Del(headerKey)
+			// get existing values for this header key
+			existingValues := httpHeader.Values(headerKey)
+			existingValuesMap := make(map[string]bool)
+			for _, v := range existingValues {
+				existingValuesMap[v] = true
+			}
+
+			// add only values that don't already exist
 			for _, headerValue := range headerValues {
-				httpHeader.Add(headerKey, headerValue)
+				if !existingValuesMap[headerValue] {
+					httpHeader.Add(headerKey, headerValue)
+				}
 			}
 		}
 	}