mcpbeat

Minecraft Resource Pack

jahrome907/minecraft-agent-.codex-minecraft-resource-pack

Create and edit Minecraft resource packs for 1.21.x including custom block models, item models, blockstate definitions, textures (PNG format requirements), sounds.json, custom fonts, MCMETA animation files, OptiFine CIT (Custom Item Textures), and pack.mcmeta format. Covers the full block/item model JSON schema (parent, textures, elements, display, overrides), multi-layer items, GUI textures, GUI sprites, language files, shader integration (core shaders, Iris), and the pack format numbers for each 1.21.x version. Use to customize how Minecraft looks and sounds without mods.

This is a copy. The original lives at jahrome907/minecraft-resource-pack.

8k tokens
context cost
the whole folder, loaded on every use
3
files
ships runnable scripts
0
copies elsewhere
how many repositories repackaged it
105
stars on the repo
on the repository, not the skill itself

Install

one command, takes just this skill from the repository 
npx skills add https://github.com/Jahrome907/minecraft-agent-skills --skill minecraft-resource-pack

What comes with it

16 041 bytes besides the instruction
scripts/jq-shim.mjs
scripts/validate-resource-pack.sh

The instruction itself

38 sections, as written by the author

Minecraft Resource Pack Skill

What Is a Resource Pack?

A resource pack is a folder (or .zip) that overrides or adds Minecraft's visual and

audio assets: textures, models, sounds, language files, fonts, and shaders. No Java

or mod loader required. Works on vanilla clients and servers.

Routing Boundaries

  • Use when: the deliverable is visual/audio assets (textures, models, sounds, fonts, shaders) in resource-pack format.
  • Do not use when: the task requires gameplay logic or runtime behavior changes (use minecraft-datapack, minecraft-plugin-dev, or minecraft-modding).
  • Do not use when: the task is server infrastructure/runtime administration (minecraft-server-admin).

Pack Metadata (1.21.x)

| Minecraft Version | Preferred pack metadata |

|-------------------|---------------------------|

| 1.21 / 1.21.1 | pack_format: 34 |

| 1.21.2 / 1.21.3 | pack_format: 42 |

| 1.21.4 | pack_format: 46 |

| 1.21.5 | pack_format: 55 |

| 1.21.6 | pack_format: 63 |

| 1.21.7 / 1.21.8 | pack_format: 64 |

| 1.21.9 / 1.21.10 | min_format: [69, 0], max_format: [69, 0] |

| 1.21.11 | min_format: [75, 0], max_format: [75, 0] |

Use pack_format through 1.21.8. Starting in 1.21.9, pack.mcmeta switches to

min_format / max_format instead of the older single-number field.

For exact patch targeting, use [major, minor] arrays for both min_format and

max_format, including .0 versions such as [75, 0]. A single integer is

equivalent to [major, 0] for min_format, while a single integer in

max_format allows any minor version on that major line. Do not write decimal

JSON numbers.

Directory Layout

my-pack/
├── pack.mcmeta
├── pack.png                   ← 64×64 icon (optional)
└── assets/
    └── minecraft/             ← override vanilla (or <namespace>/ for new packs)
        ├── models/
        │   ├── block/
        │   │   └── stone.json
        │   └── item/
        │       └── diamond_sword.json
        ├── items/              ← 1.21.4+ item model definitions
        │   └── diamond_sword.json
        ├── blockstates/
        │   └── stone.json
        ├── textures/
        │   ├── block/
        │   │   └── stone.png
        │   ├── item/
        │   │   └── diamond_sword.png
        │   ├── gui/
        │   │   └── sprites/
        │   │       └── my_sprite.png
        │   └── entity/
        │       └── zombie/
        │           └── zombie.png
        ├── sounds/
        │   └── custom/
        │       └── my_sound.ogg
        ├── sounds.json
        ├── font/
        │   └── default.json
        ├── lang/
        │   └── en_us.json
        ├── shaders/           ← core shader overrides (advanced)
        └── optifine/          ← OptiFine CIT / CTM (OptiFine only)
            └── cit/
                └── my_item.properties

pack.mcmeta

1.21.8 and earlier

{
  "pack": {
    "pack_format": 64,
    "description": "My Custom Resource Pack v1.0"
  }
}

1.21.9 / 1.21.10

{
  "pack": {
    "min_format": [69, 0],
    "max_format": [69, 0],
    "description": "My Custom Resource Pack v1.0"
  }
}

1.21.11

{
  "pack": {
    "min_format": [75, 0],
    "max_format": [75, 0],
    "description": "My Custom Resource Pack v1.0"
  }
}

Block Models

assets/minecraft/models/block/my_cube.json

Full cube — all six faces use the same texture:

{
  "parent": "minecraft:block/cube_all",
  "textures": {
    "all": "minecraft:block/stone"
  }
}

Column block (like logs):

{
  "parent": "minecraft:block/cube_column",
  "textures": {
    "end": "mypack:block/my_pillar_top",
    "side": "mypack:block/my_pillar_side"
  }
}

Different sides:

{
  "parent": "minecraft:block/cube",
  "textures": {
    "up":    "mypack:block/my_block_top",
    "down":  "mypack:block/my_block_bottom",
    "north": "mypack:block/my_block_side",
    "south": "mypack:block/my_block_side",
    "east":  "mypack:block/my_block_side",
    "west":  "mypack:block/my_block_side",
    "particle": "mypack:block/my_block_side"
  }
}

Cross model (flowers, plants):

{
  "parent": "minecraft:block/cross",
  "textures": {
    "cross": "mypack:block/my_flower"
  }
}

Custom geometry (elements)

{
  "credit": "Custom model",
  "ambientocclusion": true,
  "textures": {
    "0": "mypack:block/panel",
    "particle": "mypack:block/panel"
  },
  "elements": [
    {
      "from": [0, 0, 7],
      "to": [16, 16, 9],
      "faces": {
        "north": { "texture": "#0", "uv": [0, 0, 16, 16] },
        "south": { "texture": "#0", "uv": [0, 0, 16, 16] }
      }
    }
  ],
  "display": {
    "thirdperson_righthand": {
      "rotation": [75, 45, 0],
      "translation": [0, 2.5, 0],
      "scale": [0.375, 0.375, 0.375]
    }
  }
}

> from and to are in 1/16th block units (0–16). uv is [x1, y1, x2, y2] in 0–16 units.

Item Models

Simple flat item

{
  "parent": "minecraft:item/generated",
  "textures": {
    "layer0": "mypack:item/my_item"
  }
}

Held item (in-hand model)

{
  "parent": "minecraft:item/handheld",
  "textures": {
    "layer0": "mypack:item/my_sword"
  }
}

Two-layer item (colored like leather armor)

{
  "parent": "minecraft:item/generated",
  "textures": {
    "layer0": "minecraft:item/leather_helmet",
    "layer1": "minecraft:item/leather_helmet_overlay"
  }
}

Custom model data overrides (1.21.4 and prior)

Each predicate entry routes to a different model based on custom_model_data:

{
  "parent": "minecraft:item/handheld",
  "textures": {
    "layer0": "minecraft:item/stick"
  },
  "overrides": [
    { "predicate": { "custom_model_data": 1001 }, "model": "mypack:item/magic_wand" },
    { "predicate": { "custom_model_data": 1002 }, "model": "mypack:item/fire_staff" }
  ]
}

1.21.4+ Item Model (new format)

In 1.21.4, Mojang introduced a new item model system. Place model definitions at

assets/<namespace>/items/<item_name>.json:

{
  "model": {
    "type": "minecraft:select",
    "property": "minecraft:custom_model_data",
    "fallback": {
      "type": "minecraft:model",
      "model": "minecraft:item/stick"
    },
    "cases": [
      {
        "when": 1001,
        "model": { "type": "minecraft:model", "model": "mypack:item/magic_wand" }
      }
    ]
  }
}

Blockstate Definitions

Simple block (no variants)

{
  "variants": {
    "": { "model": "mypack:block/my_block" }
  }
}

Facing block (4 rotations)

{
  "variants": {
    "facing=north": { "model": "mypack:block/my_block" },
    "facing=south": { "model": "mypack:block/my_block",  "y": 180 },
    "facing=east":  { "model": "mypack:block/my_block",  "y": 90  },
    "facing=west":  { "model": "mypack:block/my_block",  "y": 270 }
  }
}

Random texture (multipart)

{
  "variants": {
    "": [
      { "model": "minecraft:block/grass_block",  "weight": 3 },
      { "model": "minecraft:block/grass_block_2" }
    ]
  }
}

Multipart (slabs, fences, walls)

{
  "multipart": [
    { "apply": { "model": "mypack:block/my_slab_bottom" }, "when": { "type": "bottom" } },
    { "apply": { "model": "mypack:block/my_slab_top"    }, "when": { "type": "top"    } },
    { "apply": { "model": "mypack:block/my_block"        }, "when": { "type": "double" } }
  ]
}

Textures

  • Format: PNG, RGBA (32-bit)
  • Standard block/item size: 16×16 px
  • Textures can be larger (32×32, 64×64) — Minecraft scales them, but stick to powers of 2
  • Animation requires height = N × width (e.g., 16×64 for 4 frames)
  • Place block textures in assets/<namespace>/textures/block/
  • Place item textures in assets/<namespace>/textures/item/
  • All textures are referenced without the .png extension in JSON

Animated texture MCMETA

assets/minecraft/textures/block/fire_0.png.mcmeta:

{
  "animation": {
    "frametime": 2,
    "frames": [0, 1, 2, 3, 4, 5, 6, 7]
  }
}

If frames is omitted, all frames play sequentially. frametime is in game ticks (default 1).

GUI sprites (1.20.2+)

Place sprites at assets/minecraft/textures/gui/sprites/<category>/<name>.png.

Reference them with <category>/<name> in code/JSON.

Sounds

assets/minecraft/sounds.json

{
  "my_sound.play": {
    "sounds": [
      { "name": "mypack:custom/my_sound", "volume": 1.0, "pitch": 1.0, "weight": 1 },
      { "name": "mypack:custom/my_sound_alt", "weight": 2 }
    ],
    "category": "players"
  },
  "entity.player.levelup": {
    "replace": true,
    "sounds": [
      { "name": "mypack:custom/levelup_replaced", "volume": 0.75, "pitch": 1.0 }
    ]
  }
}
  • Sound files go in assets/<namespace>/sounds/ as .ogg files (Vorbis encoded)
  • Use "replace": true to replace vanilla sounds instead of adding to them
  • Categories: master, music, record, weather, block, hostile, neutral, player, ambient, voice

Language Files

assets/minecraft/lang/en_us.json:

{
  "block.mypack.my_block": "My Custom Block",
  "item.mypack.my_item": "Magic Wand",
  "entity.mypack.my_mob": "Forest Guardian",
  "death.attack.mypack.laser": "%1$s was zapped by %2$s"
}
  • Use the exact translation key format for your mod/datapack namespace
  • File name is the locale code (e.g., fr_fr.json, de_de.json)
  • Always provide en_us.json as the primary fallback

Fonts

assets/minecraft/font/default.json — add glyph

{
  "providers": [
    {
      "type": "bitmap",
      "file": "mypack:font/icons.png",
      "ascent": 8,
      "height": 9,
      "chars": ["\uE000", "\uE001", "\uE002"]
    }
  ]
}

Custom icons via private use area (U+E000–U+F8FF). Reference in text with \uE000.

The icons.png must have each character cell height pixels tall.

OptiFine CIT (Custom Item Textures)

> OptiFine-only feature. Does not work in vanilla or Iris.

assets/minecraft/optifine/cit/my_sword.properties

type=item
items=minecraft:diamond_sword
texture=my_sword_texture.png
model=my_sword_model
nbt.display.Name=ipattern:*Excalibur*

Common CIT properties:

  • type=item — item texture override
  • type=enchantment — custom enchantment glint
  • type=armor — armor overlay
  • items= — comma-separated item IDs
  • damage= — damage range (e.g., 0-50%)
  • nbt.display.Name=ipattern:*text* — NBT name filter
  • texture= — PNG file (relative to .properties file)
  • model= — JSON model file (relative)

Iris Shaders (Resource Pack Method)

Iris shaders live inside a resource pack at:

assets/iris/
    shaders/
        core/
            rendertype_terrain.vsh    ← vertex shader override
            rendertype_terrain.fsh    ← fragment shader override

Full shader pack distribution uses the .zip format with a shaders/ root folder

(not inside assets/). Resource pack shader overrides target specific render types.

Installation

# Singleplayer: place in
~/.minecraft/resourcepacks/my-pack/
# or
~/.minecraft/resourcepacks/my-pack.zip

# Server-side (forces on clients):
# Set in server.properties:
resource-pack=https://example.com/my-pack.zip
resource-pack-sha1=<sha1 hash>
resource-pack-prompt={"text":"Required pack","color":"gold"}

Common Issues

| Problem | Cause | Fix |

|---------|-------|-----|

| Model not showing | Wrong JSON path or syntax error | Check assets/<namespace>/models/ path; validate JSON |

| Black/pink checkerboard | Texture path wrong or missing | Check textures/ path, file extension not in JSON |

| Blockstate not applying | Wrong state property name | Match exact property names from /blockdata |

| Animation not working | Wrong MCMETA location | Must be same folder as texture, named texture.png.mcmeta |

| Custom sound not playing | Not in sounds.json | Register sound event in sounds.json, match namespace |

| Pack not loading | Wrong pack_format or min_format / max_format values | Update pack.mcmeta for the exact 1.21.x patch |

Validator Script

Use the bundled validator script before shipping a resource-pack update:

# Run from the installed skill directory (for example `.claude/skills/minecraft-resource-pack`):
./scripts/validate-resource-pack.sh --root /path/to/resource-pack

# Strict mode treats warnings as failures:
./scripts/validate-resource-pack.sh --root /path/to/resource-pack --strict

What it checks:

  • JSON validity for pack.mcmeta and assets/**/*.json
  • Model/blockstate/font/sounds references resolve to real files
  • Every *.png.mcmeta has a matching *.png

References

  • Minecraft Wiki — Resource pack: https://minecraft.wiki/w/Resource_pack
  • Minecraft Wiki — Model: https://minecraft.wiki/w/Tutorials/Models
  • Minecraft Wiki — Blockstates: https://minecraft.wiki/w/Blockstate_(Java_Edition)
  • Pack format history: https://minecraft.wiki/w/Pack_format
  • Misode's model viewer: https://misode.github.io/
  • OptiFine CIT guide: https://optifine.readthedocs.io/cit.html

How to use it

Copy the folder

Take jahrome907/minecraft-agent-.codex-minecraft-resource-pack from the repository into ~/.claude/skills for personal use, or into .claude/skills inside a project.

Check the name does not clash

The agent identifies a skill by the name field in its header. Two skills with the same name cannot sit side by side — one of them will be ignored.