Brigadier

Brigadier
Author(s)	Mojang Studios
Written in	Java
Latest release	1.0.18
License	MIT License
Source code	brigadier

	“	I'm so proud of that name! Brigadier is the name of the command engine that Minecraft uses.	„
		— Dinnerbone on Brigadier

Brigadier is a command parser and dispatcher, designed and developed for Java Edition, mainly maintained by Dinnerbone. It is the first library used by Java Edition that Mojang has released under an open-source license.

Usage

Brigadier is used for parsing and executing string commands.

Features

• Define command nodes with argument or literal branches
  • All the commands available in Java Edition are actually the literal branches available for the root command nodes instead of the actual executed commands.
• Modify/fork command source in command contexts
  • /execute as <target selector> may modify the command source to be multiple when multiple entities are selected
• Active inspection on command parsing
• Listing all possible commands from current command node
• Handle command result real-time on execution success/failure
  • /execute store can store the command result to block/entity NBT data or scoreboard
• Recursive command node redirection
  • /execute run redirects to the root node of the vanilla command dispatcher

Limitations and issues

Brigadier has various numbers of limitations while executing the command, such as the numeric limitations on integer data types such as /effect, /weather, and floating-point data types such as /time, making many integer values parsed in the commands inaccessible.

Since 1.15, whenever the chat cursor is positioned at the start of a node after a whitespace character, command suggestion will say "Incorrect argument for command at position <position number>" instead of displaying the command suggestions, especially the command arguments that requires numbers or strings before parsing and the trailing spaces beyond the command argument list.

History

October 25, 2014					Dinnerbone mentions Brigadier in the comments on MC-10880.
July 27, 2017					Dinnerbone discloses a non-obfuscated command parser library called "brigadier".
Java Edition
1.13		17w45a			Commands are now handled with Brigadier.
					Minecraft introduces Brigadier as a dependency.
September 26, 2018					Brigadier is open sourced under the MIT License.
1.14		19w08a			Now allows single quotes for strings in commands.

Version history

Version	Date	Changes
1.0.15	September 26, 2018	Initial release
1.0.17	February 19, 2019	Allow single quotes in strings Added long argument Implement calculation of suggestions for any text position No longer depend on Guava
1.0.18	July 16, 2021	Peformance optimizations

Gallery

• 
  The /execute command tree, which utilizes an overwhelming amount of the brigadier features.
• 
  The /tag command tree, showing the difference between actual executed commands (red nodes) versus the first literal after the root (the "tag" box)
• 
  The /msg command tree, showing that aliases have been implemented by brigadier's command node redirection functionality (dashed lines)