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Allow you to store and manipulate collections of data. They can be declared in a concise and readable manner, supporting both single-line and multi-line formats.

## Syntax

To declare an array in a BAML file, you can use the following syntax:

```baml
{
  key1 [value1, value2, value3],
  key2 [
    value1,
    value2,
    value3
  ],
  key3 [
    {
      subkey1 "valueA",
      subkey2 "valueB"
    },
    {
      subkey1 "valueC",
      subkey2 "valueD"
    }
  ]
}
```

### Key Points:

* **Commas**: Optional for multi-line arrays, but recommended for clarity.
* **Nested Arrays**: Supported, allowing complex data structures.
* **Key-Value Pairs**: Arrays can contain objects with key-value pairs.

## Usage Examples

### Example 1: Simple Array

```baml
function DescriptionGame(items: string[]) -> string {
    client "openai/gpt-5-mini"
    prompt #"
        What 3 words best describe all of these: {{ items }}.
    "#
}

test FruitList {
    functions [DescriptionGame]
    args { items ["apple", "banana", "cherry"] }
}
```

### Example 2: Multi-line Array

```baml
test CityDescription {
    functions [DescriptionGame]
    args { items [
            "New York",
            "Los Angeles",
            "Chicago"
        ]
    }
}
```