What this validator checks
A practical preflight for Bedrock add-ons and packs
Pack Doctor opens the archive locally, discovers behavior packs, resource packs, script packs and world templates, then checks every JSON file before examining each manifest. It catches malformed JSON, missing manifest fields, invalid or repeated UUIDs, bad versions, broken dependencies, missing script entry files, missing texture references and pack icon problems.
The checks are based on the public Minecraft Creator documentation and the open-source Minecraft Creator Tools rules published by Mojang. Rule IDs in this report are stable MC Toolbox identifiers so exported reports can be compared between builds.
Manifest and UUID checks
Validates format versions 1, 2 and preview 3, header and module fields, UUID uniqueness, dependencies, script modules and minimum engine versions.
Files and assets
Parses all JSON files, follows common texture references, verifies script entry paths, checks nested .mcpack files and identifies wrapper folders or operating-system junk.
Private browser analysis
The archive is read with JavaScript in your current tab. No pack, UUID, script or texture is sent to MC Toolbox or another server.
Pack Doctor versus Mojang Minecraft Creator Tools
This browser tool is intended for fast checks before import, sharing or Marketplace submission. It does not claim to replace the official Minecraft Creator Tools command-line validator. Mojang's validator can run deeper content schemas, deprecated-feature rules and engine-aware checks that require Node.js, a project filesystem or current game data. For release-critical packs, fix the browser report first and then run the official mct validate command.
Frequently asked questions
Can this repair my add-on automatically?
No. Automatic edits can damage UUID relationships and version targets. The report explains the problem and a safe correction, while leaving your original archive unchanged.
Does it support .mcaddon and .mcpack files?
Yes. A .mcaddon can contain multiple nested packs. Pack Doctor expands common nested .mcpack and ZIP archives and checks each discovered manifest separately.
Why is format_version 3 marked as preview?
Mojang documents manifest format 3 as preview. Stable behavior and resource packs normally use format 2, while older skin-pack content can still use format 1.
Is a 256 x 256 pack icon required?
Mojang's validator accepts square power-of-two PNG sizes from 2 to 256 pixels. A 256 x 256 icon remains the clearest conventional choice, but smaller valid square sizes are not errors.