- Loaders
- Fabric
- Downloads on Modrinth
- 2K
- Followers on Modrinth
- 4
- versions
- 51
- Updated
- October 7, 2026Oct 7
- Published
- in 2025
At a glance
Works both in the game and on the server — install where you need it
Codec2Schema
Through the power of mixins, sheer will, and unchecked type casts, this mod transforms codecs into (mostly) usable JSON schemas.
You can find the generated schemas for vanilla Minecraft here.
What is a Codec?
Codecs are Mojang's way of easily serializing data to and from JSON. They define the structure of an object, meaning JSON schemas can be generated from them.
What is a JSON Schema?
A JSON schema is a file that describes how JSON files should be structured, and can be used by IDEs to provide autocomplete when creating or editing JSON files.
About This Mod
When installed, this mod exports JSON schemas for data and resource pack files to `/codec2schema`. You can use the API to export your own codecs as well!
The generated JSON schemas will have autocomplete for registries (items, blocks, etc), including modded content.
This mod is not perfect: there are many edge cases that aren't or can't be accounted for.
Example
The following is the generated JSON schema for regional compliancies warnings:
{
"$schema": "https://json-schema.org/draft-07/schema",
"$ref": "#/definitions/def",
"definitions": {
"def": {
"type": "object",
"propertyNames": {
"type": "string"
},
"additionalProperties": {
"type": "array",
"items": {
"$ref": "#/definitions/def_1"
}
}
},
"def_1": {
"type": "object",
"properties": {
"delay": {
"type": "integer",
"minimum": -9223372036854775808,
"maximum": 9223372036854775807,
"default": 0
},
"period": {
"type": "integer",
"minimum": -9223372036854775808,
"maximum": 9223372036854775807
},
"title": {
"type": "string"
},
"message": {
"type": "string"
}
},
"required": [
"period",
"title",
"message"
]
}
}
}It's not perfect, but it's good enough.
FAQ
How to install Codec2Schema?
Install Fabric for your Minecraft version, download Codec2Schema for the same version and loader, put the file into the mods folder and launch the game with the loader profile.
Which Minecraft versions does Codec2Schema support?
Codec2Schema has builds for Minecraft 1.21.11–26.3.
Is Codec2Schema needed on the server?
Works on either side — install it in the game, on the server, or both
