diff --git a/server-rs/crates/platform-image/src/vector_engine/raw_edit.rs b/server-rs/crates/platform-image/src/vector_engine/raw_edit.rs
index c4399f3de..a749f06db 100644
--- a/server-rs/crates/platform-image/src/vector_engine/raw_edit.rs
+++ b/server-rs/crates/platform-image/src/vector_engine/raw_edit.rs
@@ -154,6 +154,8 @@ pub async fn create_vector_engine_raw_image_edit(
         .text("prompt", prompt.to_string())
         .text("size", format!("{}x{}", options.width, options.height))
         // GPT-Image-2 原生只返回 b64_json；不要添加 URL 下载或 response_format 兼容分支。
+        // `Part::bytes` 只接受 `Cow<[u8]>`，会迫使 `Bytes` 复制成 `Vec`；stream Body
+        // 直接接管共享缓冲，避免 raw_edit 请求的整图/掩码额外分配和峰值内存。
         .part(
             "image",
             Part::stream(reqwest::Body::from(image_bytes))