LiveNBTEditor vs MCA JSON

LiveNBTEditor edits Minecraft NBT data while a game is running, applying validated changes on the next game tick instead of requiring file editing or a world reload. A Java agent runs a WebSocket server, and a Windows desktop editor connects to it; the agent can run where Minecraft runs, including Linux dedicated servers. The project says it works with vanilla Minecraft without a mod loader. The editor can change player data and world settings such as gamerules, time, weather, spawn, world border, and difficulty. It includes live watches, deep search, SNBT editing, clipboard support, keyboard shortcuts, undo, and redo. It can edit all 41 player inventory slots, with searchable item and enchantment pickers based on the bundled Minecraft 26.3 registry. SNBT can be copied and pasted with NBT Studio. The project specifies Minecraft Java 26.3 and says other versions are unsupported. The agent binds to loopback by default and requires a per-install token, but the WebSocket connection is unencrypted. LiveNBTEditor is free and MIT-licensed; its README warns that live edits can corrupt data and recommends backing up important worlds.

MCA JSON is a command-line toolkit and TypeScript library for handling Minecraft Java Edition region and data files. Its commands convert MCA and NBT data to JSON and back, list chunks, find signs, remove chunks, and inspect player locations. The library supplies typed methods for parsing and changing MCA, NBT, and SNBT data. The maker reports region structure and NBT reading across versions, with files tried from Minecraft 1.2.1 through 1.21. It reads zlib, gzip, LZ4, and uncompressed chunks; changes are saved with zlib. Installation is documented through npm, with Deno, Bun, pnpm, and other package managers also usable. The library can be bundled for browser use, is distributed only as ES modules, and requires Node.js 20 or newer. It supports Java Edition, not Bedrock. Separate .mcc chunks over 1 MiB and chunks using custom compression cannot be read, though they can be listed and removed. A largely untouched region produced about 1 gigabyte of JSON in an example; compact and condensed output options are documented. The software is free.