re-enqueue amazon bedrock 503 failed requests

src/proxy/middleware/response/index.ts

@@ -401,13 +401,15 @@ const handleUpstreamErrors: ProxyResHandlerWithBody = async (
   } else if (statusCode === 503) {
     switch (service) {
       case "aws":
-        if (
-          errorType === "ServiceUnavailableException" &&
-          errorPayload.error?.message?.match(/too many connections/i)
-        ) {
-          errorPayload.proxy_note = `The requested AWS Bedrock model is overloaded. Try again in a few minutes, or try another model.`;
-        }
-        break;
+        // Re-enqueue on any 503 from AWS Bedrock
+        req.log.warn(
+          { key: req.key?.hash, errorType, errorPayload },
+          `AWS Bedrock service unavailable (503). Re-enqueueing request.`
+        );
+        await reenqueueRequest(req);
+        throw new RetryableError(
+          "AWS Bedrock service unavailable (503), re-enqueued request."
+        );
       default:
         errorPayload.proxy_note = `Upstream service unavailable. Try again later.`;
         break;