diff --git a/src-tauri/src/proxy/handlers.rs b/src-tauri/src/proxy/handlers.rs
index b16bf2715..96076470d 100644
--- a/src-tauri/src/proxy/handlers.rs
+++ b/src-tauri/src/proxy/handlers.rs
@@ -1005,19 +1005,39 @@ fn codex_proxy_error_json(
return body;
};
- let cause = error_obj
- .get("message")
- .and_then(|value| value.as_str())
- .map(ToString::to_string)
- .filter(|message| !message.trim().is_empty())
- .unwrap_or_else(|| get_error_message(error));
-
- let status_fragment = upstream_status
- .map(|status| format!("; upstream_status: HTTP {status}"))
- .unwrap_or_default();
- let message = format!(
- "CC Switch local proxy failed while handling Codex endpoint {endpoint}. Provider: {provider_name}; model: {request_model}{status_fragment}; cause: {cause}"
- );
+ let message = if upstream_status == Some(413) {
+ // 413 来自上游渠道商的网关（典型是 nginx 的 client_max_body_size），不是 CC
+ // Switch 本地代理的限制（本地 DefaultBodyLimit 已放到 200MB）。上游响应体往往是
+ // 一整段 nginx HTML，对用户毫无价值，这里替换成明确指向上游 + 可操作的指引，
+ // 避免「以为是 CC Switch 封装了 nginx / 是本地代理的锅」这种反复出现的误解。
+ format!(
+ concat!(
+ "Upstream provider rejected the request with HTTP 413 (Payload Too Large). ",
+ "The request body exceeds the upstream gateway's size limit; this is the ",
+ "provider's server-side limit, not a CC Switch limit. ",
+ "Provider: {provider}; model: {model}; endpoint: {endpoint}. ",
+ "To recover, shrink the request: run /compact, remove large pasted logs or ",
+ "inline images, or ask the provider to raise its request body limit ",
+ "(e.g. nginx client_max_body_size)."
+ ),
+ provider = provider_name,
+ model = request_model,
+ endpoint = endpoint,
+ )
+ } else {
+ let cause = error_obj
+ .get("message")
+ .and_then(|value| value.as_str())
+ .map(ToString::to_string)
+ .filter(|message| !message.trim().is_empty())
+ .unwrap_or_else(|| get_error_message(error));
+ let status_fragment = upstream_status
+ .map(|status| format!("; upstream_status: HTTP {status}"))
+ .unwrap_or_default();
+ format!(
+ "CC Switch local proxy failed while handling Codex endpoint {endpoint}. Provider: {provider_name}; model: {request_model}{status_fragment}; cause: {cause}"
+ )
+ };
error_obj.insert(
"message".to_string(),
@@ -1477,4 +1497,36 @@ data: {\"type\":\"response.output_item.done\",\"item\":{\"type\":\"message\"}}\n
assert_eq!(body["error"]["code"], 2013);
assert_eq!(body["error"]["upstream_status"], 502);
}
+
+ #[test]
+ fn codex_proxy_413_points_to_upstream_not_local_proxy() {
+ // 模拟上游渠道商 nginx 因 client_max_body_size 返回的 413 HTML 页面
+ // （见 issue #666：长上下文 / 大图 / 大日志撞上游体积上限）
+ let error = ProxyError::UpstreamError {
+ status: 413,
+ body: Some(
+ "\r\n413 Request Entity Too Large\r\n\
+ \r\n413 Request Entity Too Large
\r\n\
+
nginx/1.29.6\r\n\r\n"
+ .to_string(),
+ ),
+ };
+ let body = codex_proxy_error_json("HCAI", "gpt-5.5", "/responses", &error);
+
+ let message = body["error"]["message"].as_str().unwrap();
+ // 不再误导成「本地代理失败」
+ assert!(!message.contains("CC Switch local proxy failed"));
+ // 明确指向上游 + 体积超限 + 可操作指引
+ assert!(message.contains("413"));
+ assert!(message.to_lowercase().contains("upstream"));
+ assert!(message.contains("/compact"));
+ // 关键：不把整段 nginx HTML 回显给用户
+ assert!(!message.contains(""));
+ assert!(!message.contains("nginx/1.29.6"));
+ // 结构化字段仍然保留，便于程序化消费 / UI 呈现
+ assert_eq!(body["error"]["upstream_status"], 413);
+ assert_eq!(body["error"]["provider"], "HCAI");
+ assert_eq!(body["error"]["model"], "gpt-5.5");
+ assert_eq!(body["error"]["endpoint"], "/responses");
+ }
}