# `type.type_argument_count`

Type has the wrong number of type arguments.

Area 2, [Values and types](../topics/values-and-types.md); not declinable; the next step is usually the agent's.

```jadpo
type Tag = Text {
    max_length: 30
}

type Basket = Object {
    tags: List<Tag, Tag>
}
```

```text
error: `List` takes one type argument, as in `List<Tag>`
 --> main.jadpo:6:11
  |
6 |     tags: List<Tag, Tag>
  |           ^^^^^^^^^^^^^^ 2 given
  reason: `List` holds values of the type in `< >`, so it needs exactly 1.
  next: Write `List` with one type argument, as in `List<Tag>` (agent)
  rule: type.type_argument_count
  help: https://jadpo.dev/docs/errors/type.type_argument_count

check failed: 1 error, 1 file
```