> For the complete documentation index, see [llms.txt](https://docs.ltonetwork.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ltonetwork.com/protocol/public/transactions/set-script.md).

# Set Script

Smart accounts have a custom script that defines how transactions should be validated. The script needs to be compiled by the node before it's broadcasted as a transaction.

Scripts are written in the [Ride programming language](https://docs.waves.tech/en/ride/).

```javascript
{
	"type": 13,
	"version": 3,
	"id": "BGUEn2TERW4nnAQuXYgJ3z6qp28ivk3kykb724wV7MZz",
	"sender": "3MtHYnCkd3oFZr21yb2vEdngcSGXvuNNCq2",
	"senderKeyType": "ed25519",
	"senderPublicKey": "4EcSxUkMxqxBEBUBL2oKz3ARVsbyRJTivWpNrYQGdguz",
	"script": "base64:AQkAAfQAAAADCAUAAAACdHgAAAAJYm9keUJ5dGVzCQABkQAAAAIIBQAAAAJ0eAAAAAZwcm9vZnMAAAAAAAAAAAAIBQAAAAJ0eAAAAA9zZW5kZXJQdWJsaWNLZXmmsz2x",
	"timestamp": 1519862400,
	"fee": 500000000,
	"proofs": [
	  "jxW9T2iUSQ68yv41Wj8JKb8HykwzKzbuHLBG6eySLaXk45rNbDo3zr2AS9bGMggrBZUUJQTFjKHeiD1q69pPUxY"
	],
	"height": 1248629
}
```

### Examples

#### Restrict account

```javascript
match tx {
  case t:  TransferTransaction => false
  case mt: MassTransferTransaction => false
  case ss: SetScriptTransaction => false
  case _ => sigVerify(tx.bodyBytes, tx.proofs[0], tx.senderPublicKey)
}
```

The "Restrict Account" script disables transfers from the account, it also disables modifying the script. This means that any funds on the account can only be used for staking/leasing and paying transaction fees.

### Binary schema

The binary data structure of the unsigned transaction.

{% tabs %}
{% tab title="V3 (current)" %}

| # |      Field Name     |           Type           | Length   |
| - | :-----------------: | :----------------------: | -------- |
| 1 |   Transaction type  | Byte (constant, value=4) | 1        |
| 2 |       Version       | Byte (constant, value=3) | 1        |
| 3 |      Network id     |           Byte           | 1        |
| 4 |      Timestamp      |           Long           | 8        |
| 5 |  Sender's key type  |      KeyType (Byte)      | 1        |
| 6 | Sender's public key | PublicKey (Array\[Byte]) | 32 \| 33 |
| 7 |         Fee         |           Long           | 8        |
| 8 |  Script length (N)  |           Short          | 2        |
| 9 |        Script       |       Array\[Byte]       | N        |

{% hint style="info" %}

* Script is the (binary) compiled script (without "base64:" prefix).
* Network id can be obtained by taking the 2nd byte from the sender address.
* Each [key type](/protocol/accounts.md#key-types) has a numeric id in addition to the reference from the JSON.
* Integers (short, int, long) have a big endian byte order.
  {% endhint %}
  {% endtab %}

{% tab title="V1" %}

| # |      Field Name     |           Type           | Length |
| - | :-----------------: | :----------------------: | ------ |
| 1 |   Transaction type  | Byte (constant, value=4) | 1      |
| 2 |       Version       | Byte (constant, value=1) | 1      |
| 3 |      Network id     |           Byte           | 1      |
| 4 | Sender's public key | PublicKey (Array\[Byte]) | 32     |
| 5 |   Includes script   |      Boolean (Byte)      | 1      |
| 6 |  Script length (N)  |           Short          | 2      |
| 7 |        Script       |       Array\[Byte]       | N      |
| 8 |         Fee         |           Long           | 8      |
| 9 |      Timestamp      |           Long           | 8      |

{% hint style="warning" %}
If the transaction doesn't include a script, the script length and script should be omitted from the binary data.
{% endhint %}

{% hint style="info" %}

* Script is the (binary) compiled script (without "base64:" prefix).
* Network id can be obtained by taking the 2nd byte from the sender address.
* Each [key type](/protocol/accounts.md#key-types) has a numeric id in addition to the reference from the JSON.
* Integers (short, int, long) have a big endian byte order.
  {% endhint %}
  {% endtab %}
  {% endtabs %}