> For the complete documentation index, see [llms.txt](https://inside-scripts.gitbook.io/documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://inside-scripts.gitbook.io/documentation/free-scripts/bridge-and-library/functions/library/callback/server.md).

# Server

## <mark style="color:green;">registerCallback</mark>

### Usage

```lua
Lib.registerCallback(event, callback, ...)
```

* event: `string`
* callback: `function`
* ...: `any`

### Example

```lua
Lib.registerCallback("example:doubleNumber", function(src, cb, number)
    local doubleNumber = number * 2
    
    cb(doubleNumber)
end)
```

## <mark style="color:green;">deleteCallback</mark>

### Usage

```lua
Lib.deleteCallback(event, invoker)
```

* event: `string`
* invoker(optional): `string`

### Example

```lua
Lib.deleteCallback("example:doubleNumber")
```