> For the complete documentation index, see [llms.txt](https://move-developers-dao.gitbook.io/aptos-move-by-example/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://move-developers-dao.gitbook.io/aptos-move-by-example/basic-concepts/scripts.md).

# Scripts

*Scripts* are executable entrypoints similar to a `main` function in a conventional language. A script typically calls functions of a published module that perform updates to global storage. Scripts are ephemeral code snippets that are not published in global storage.

A Move source file (or **compilation unit**) may contain multiple modules and scripts. However, publishing a module or executing a script are separate VM operations.

**Syntax**

A script has the following structure:

```rust
script {
    <use>*
    <constants>*
    fun <identifier><[type parameters: constraint]*>([identifier: type]*) <function_body>
}
```

A `script` block must start with all of its `use` declarations, followed by any `constants` and (finally) the main `function` declaration. The main function can have any name (i.e., it need not be called `main`), is the only function in a script block, can have any number of arguments, and must not return a value. Here is an example with each of these components:

```rust
script {
    // Import the debug module published at the named account address std.
    use std::debug;

    const ONE: u64 = 1;

    fun main(x: u64) {
        let sum = x + ONE;
        debug::print(&sum)
    }
}
```

Scripts have very limited power—they cannot declare friends, struct types or access global storage. Their primary purpose is to invoke module functions.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://move-developers-dao.gitbook.io/aptos-move-by-example/basic-concepts/scripts.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.