[UPDATE] Clarify API Cost Risks when using Secrets in Public Hugging Face Spaces (Unit 1)

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Hi team,

I was going through **Unit 1** in the section **"Let’s Create Our First Agent Using smolagents,"** (specifically, this page: https://huggingface.co/learn/agents-course/unit1/tutorial) where we set up our Hugging Face Space and add our API token as a **Secret** for the agent to use.

I had a quick question/suggestion about the cost implications when a Space is made public.

My understanding is that if a user makes their Space public, every person who interacts with that demo will trigger API calls that are authenticated using **the owner's token**.

If that token is for a paid service (like OpenAI or a paid Hugging Face Inference tier), that public usage could potentially start **racking up costs for the owner** of the token.

If this understanding is correct, I think it would be really helpful to add a small note or warning right after the step where we add the secret. It would be a great way to prevent students from getting any surprise bills down the road.