`hello-eval.ts` is the first local test extension.
Load it with the `rho` wrappers:
```bash
./rho -e ./extensions/hello-eval.ts user1 "Use hello_eval to evaluate 1+1."
./rho-chat -e ./extensions/hello-eval.ts user1
```
Inside interactive mode you can also run:
```text
/hello-eval-demo
```
That queues a follow-up message telling the model to call the tool.