SmartBrainLib (SBL) is a library for Minecraft mod developers who want to build more advanced mob behaviour using Minecraft's Brain system. It provides tools for memory handling, sensors, behaviours and runtime modification. It is important to understand that this is a dependency library: installing it by itself does not add new mobs, make vanilla animals smarter or provide a visible gameplay feature for most players.
What SmartBrainLib does
Minecraft's Brain system is used by some entities to manage memories and behaviours. SmartBrainLib aims to make that system easier for mod developers to configure and extend. Its public project description lists several core capabilities:
- Memory handling: helps register and manage the memory types used by an entity's brain.
- Dynamic sensors: provides configurable sensors that can gather information about the entity's surroundings.
- Advanced behaviours: includes reusable behaviour tools and supports custom behaviours with callbacks, predicates and cooldowns.
- Runtime modification: allows supported brain behaviours to be added, removed or modified while the entity is running.
- Additional utilities: includes helper functions for entity queries, random operations and interacting with brain data.
The library is intended for developers creating mobs or other mods that use the Brain system. It does not automatically replace every mob's AI in an ordinary Minecraft installation. The actual behaviour players see depends on the mod that uses the library.
Does SmartBrainLib improve performance?
The project includes optimization work in its description, but that should not be interpreted as a guaranteed server-wide performance increase. Results depend on how a mod uses the library, the entity behaviours involved, the number of active mobs and the rest of the server workload. A library can provide more efficient tools without making every modpack or world run faster automatically.
If you are troubleshooting lag, profile the server and identify the actual source of tick delays. Installing SmartBrainLib alone is not a general-purpose server optimization fix.
Supported Minecraft versions and loaders
The official Modrinth listing currently includes several Java Edition version families, including 26.3, 26.2, 26.1.2, 1.21.3–1.21.11, 1.21–1.21.1, 1.20.x, 1.19.x, 1.18.2 and 1.16.5. The project lists Fabric, Forge, NeoForge and Quilt. The supported environment includes server-side, singleplayer and client/server use.
These details can change as new releases are published. Select the file that matches the Minecraft version and mod loader required by the mod that depends on SmartBrainLib. Do not assume that a Fabric file can be used with Forge or NeoForge.
Do players need to install SmartBrainLib?
If a mod or modpack lists SmartBrainLib as a required dependency, install the matching release unless the modpack manager already includes it. If no installed mod depends on it, most players do not need to add the library manually.
For multiplayer, follow the dependency instructions for the specific mod. If the dependent mod uses SmartBrainLib for server-side entity behaviour, the library may need to be installed on the server as well as on clients, depending on that mod's requirements. The library's general environment listing is not a substitute for checking the dependent mod's own instructions.
How to install SmartBrainLib
- Identify the Minecraft version and loader required by the mod that depends on SmartBrainLib.
- Open the official SmartBrainLib project page on Modrinth.
- Select a release that matches the exact game version and loader.
- Check the dependent mod's documentation for any additional libraries or installation requirements.
- Install the library in the correct instance or server mods folder as instructed by the dependent mod.
- Launch the game or server and review the log if a dependency error appears.
When using a modpack, prefer its built-in dependency manager rather than adding another copy of the library manually. Duplicate or mismatched versions can cause dependency resolution errors.
Compatibility and troubleshooting
SmartBrainLib is designed to be used by other mods, but compatibility is not guaranteed for every combination of Minecraft version, loader and dependent project. The mod that requires SBL should state which release it expects.
- Missing dependency message: install the SmartBrainLib file required by the dependent mod.
- Wrong mod loader: replace the file with one built for the loader used by the game instance.
- Version conflict: compare the Minecraft version and dependency version in the error message with the project's release list.
- Server startup issue: inspect the first relevant error in the server log and check the dependent mod's installation instructions.
- No visible change in game: this is expected when no installed mod uses the library to add or modify entity behaviour.
Where to find documentation
SmartBrainLib's project page links to its source code, issue tracker, wiki and community channels. Developers should use those resources for API examples and version-specific details instead of copying code or configuration from unrelated tutorials. For players, the most useful documentation is often the installation page of the modpack or mob mod that declares SmartBrainLib as a dependency.
Use the official SmartBrainLib Modrinth page for current files and compatibility, and its linked wiki for developer guidance.
