> 📍 **Where to find it:** AI Agents → (your agent) → Settings

Two built-in safeguards: the agent always replies in the customer's language, and it never makes up information it doesn't have.

## How it works

Madyis Hub requires the agent to detect the language of the customer's last message and reply entirely in that language, even if its knowledge base is in French. At the same time, a strict grounding rule forbids inventing prices, lead times, policies, products or availability: if the information isn't in the knowledge base or the tools, the agent says so honestly and offers to hand over to a human. A default language only applies when the customer's language can't be determined.

## Step by step

1. These safeguards are active automatically; there's nothing to code.
2. To set the default language, open the agent, go to the "Settings" tab, and set the language.
3. Fill in the knowledge base well: the agent can only state what it contains.
4. Test in the Playground by asking a question in several languages.

## Good to know

- If the agent says "I don't have that information," it usually means the knowledge is missing from its base.
- Don't write instructions inside the knowledge base content: the agent treats them as data, not orders.
- The language rule takes priority over everything, including a base written in French.