# SEM-014: invalid action name

**Error**: the page doesn't build until this is fixed.

An action's name is part of an address (`/_a/cart.add`) and the name AI agents call it by, so it's made of
letters, digits, dots, dashes and underscores.

## Fails

```hypra fails
page(title: "Shoes", description: "All our running shoes, from light racers to trail shoes.") {
  h1 "Shoes"
  action("add to cart", id: 42) "Add to cart"
}
```

## Fixed

```hypra passes
page(title: "Shoes", description: "All our running shoes, from light racers to trail shoes.") {
  h1 "Shoes"
  action("cart.add", id: 42) "Add to cart"
}
```