Understanding .mcfunction

Table of contents

mcfunction files are stored in your BP as BP/functions/my_function.mcfunction. You can add as many functions as you like.

Functions are used to group multiple Minecraft commands (such as /say or /teleport) into managable chunks (or functions). Function files do not begin with /.

Example:

tag @s add dev
gamemode creative
effect @s night_vision 100000 1 true

Functions can be executed in game by typing /function name_of_function. This will execute all the commands in the function file, all in a single tick. Nested functions will also run in the same tick as the parent function.

Function files can be nested, for example: BP/functions/teleport/home.mcfunction will create a new function called teleport/home, which can be called in game like /function teleport/home.

Functions can be reloaded from file without leaving the game with the /reload command.

Running functions through tick.json

tick.json is server-side file located as BP/functions/tick.json that lets you execute function files.

Functions will be run each tick, as if placed in a repeating command block.

Creating tick.json

Create a file called tick.json in your root function folder. The format is this:

{
    "values": [
        "function_file_name_one",
        "function_file_name_two"
    ]
}

Known Issues

While this is a useful file when you’re trying to stray away from using repeating command blocks in-game, it’s known for executing function files before the world has fully loaded in. This might cause unintended command behavior and crashes, and it’s recommended to wait for a more official release of this file.