The runtime should therefore be built around wrappers that convert messy external services into stable functions with bounded latency and predictable failure semantics. the combination of Options A and D is the right call because it gives the platform team levers to tune behavior without rewriting the entire agent loop.
For tool agents, the two decisive signals are whether the correct tool was chosen and whether the task completed. Tokens per second is infrastructure performance, not agent competence. Within the NVIDIA stack, tool execution should sit behind adapters that can be profiled and regression-tested just like retrieval and inference services. Together, A states "Tool use accuracy"; D states "Task completion rate", so the answer covers both sides of the requirement instead of solving only the model or only the infrastructure layer.
The rejected options are weaker because hardcoded endpoints, loose parsers, or monolithic handlers turn every API change into an application release and hide failures from observability. The answer is therefore about engineered control planes, not simply model capability.