Officially, TLT provides tlt-infer for inference. They can run inference against tlt model.
Some detection networks also provide the command how to run inference against trt engine. Such as , detectnet_v2, faster_rcnn, etc. See tlt user guide or jupyter notebooks for more details.
If end user wants to run inference against trt engine without tlt-infer or deepstream, they need to write their own codes.