diff --git a/server-rs/crates/api-server/src/tripo3d/worker.rs b/server-rs/crates/api-server/src/tripo3d/worker.rs
index 24311a203..081f5129b 100644
--- a/server-rs/crates/api-server/src/tripo3d/worker.rs
+++ b/server-rs/crates/api-server/src/tripo3d/worker.rs
@@ -94,7 +94,7 @@ async fn run_model3d_job(
             // 大图、任务排在其他 job 之后），这时提交上去也只会立刻被 deadline 判失败，
             // 白花一次 provider 调用。只有还轮询得起才提交。
             ensure_submit_budget(provider_deadline)?;
-            submit_and_checkpoint(state, caller, job, &client, &request).await?
+            submit_and_checkpoint(state, caller, job, &client, &request, provider_deadline).await?
         }
     };
     let snapshot = poll_until_terminal(&client, &handle, provider_deadline).await?;
@@ -154,6 +154,9 @@ fn existing_checkpoint(job: &ExternalGenerationJobRecord) -> Option<String> {
 }
 
 /// 提交前的预算检查：本次尝试已经没有轮询预算时，不发起不可逆且计费的 provider submit。
+///
+/// 调用点有两处：进入提交流程之前，以及图生 3D 在下载 / 上传源图之后、真正 submit 之前
+/// （那两步都可能耗时到把预算用光）。
 fn ensure_submit_budget(provider_deadline: Instant) -> Result<(), AppError> {
     if Instant::now() >= provider_deadline {
         return Err(provider_deadline_error());
@@ -167,12 +170,17 @@ async fn submit_and_checkpoint(
     job: &ExternalGenerationJobRecord,
     client: &TripoProviderClient,
     request: &Model3dJobRequest,
+    provider_deadline: Instant,
 ) -> Result<TripoTaskHandle, AppError> {
     let handle = match request {
         Model3dJobRequest::TextToModel(request) => {
+            ensure_submit_budget(provider_deadline)?;
             client.submit_text_to_model(&request.generation).await
         }
         Model3dJobRequest::ImageToModel(request) => {
+            // 解析源图要先下载站内图片、再上传给 provider，这一步可能把剩下的预算用光。
+            // 提交不可撤销且计费，所以真正发起之前再确认一次：宁可本次尝试判失败，
+            // 也不要提交上去紧接着被 deadline 判失败，白花一次外部调用。
             let input = resolve_image_input(
                 state,
                 client,
@@ -180,6 +188,7 @@ async fn submit_and_checkpoint(
                 &request.source,
             )
             .await?;
+            ensure_submit_budget(provider_deadline)?;
             client
                 .submit_image_to_model(&input, &request.generation)
                 .await