Minecraft Resource Pack Skill for Claude

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.

8k tokens

context cost

the whole folder, loaded on every use

files

ships runnable scripts

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

Other skills for the same job

different authors, same section of the catalogue

Canvas Design

by anthropics

vendor ×13

Create beautiful visual art in .png and .pdf documents using design philosophy. You should use this skill when the user asks to create a poster, piece of art, design, or other static piece. Create original visual designs, never copying existing artists' work to avoid copyright violations.

Creating algorithmic art using p5.js with seeded randomness and interactive parameter exploration. Use this when users request creating art using code, generative art, algorithmic art, flow fields, or particle systems. Create original algorithmic art rather than copying existing artists' work to avoid copyright violations.

Improves the quality of images, especially screenshots, by enhancing resolution, sharpness, and clarity. Perfect for preparing images for presentations, documentation, or social media posts.

Downloads videos from YouTube and other platforms for offline viewing, editing, or archival. Handles various formats and quality options.

Lightweight WSI tile extraction and preprocessing. Use for basic slide processing tissue detection, tile extraction, stain normalization for H&E images. Best for simple pipelines, dataset preparation, quick tile-based analysis. For advanced spatial proteomics, multiplexed imaging, or deep learning pipelines use pathml.

Microscopy data management platform. Access images via Python, retrieve datasets, analyze pixels, manage ROIs/annotations, batch processing, for high-content screening and microscopy workflows.

Python library for working with DICOM (Digital Imaging and Communications in Medicine) files. Use this skill when reading, writing, or modifying medical imaging data in DICOM format, extracting pixel data from medical images (CT, MRI, X-ray, ultrasound), anonymizing DICOM files, working with DICOM metadata and tags, converting DICOM images to other formats, handling compressed DICOM data, or processing medical imaging datasets. Applies to tasks involving medical image analysis, PACS systems, radiology workflows, and healthcare imaging applications.

This skill should be used when working with pre-trained transformer models for natural language processing, computer vision, audio, or multimodal tasks. Use for text generation, classification, question answering, translation, summarization, image classification, object detection, speech recognition, and fine-tuning models on custom datasets.

13k tokens

How to use it

Copy the folder

Take jahrome907/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.

Minecraft Resource Pack Skill for Claude

Install

What comes with it

The instruction itself

Minecraft Resource Pack Skill

What Is a Resource Pack?

Routing Boundaries

Pack Metadata (1.21.x)

Directory Layout

pack.mcmeta

1.21.8 and earlier

1.21.9 / 1.21.10

1.21.11

Block Models

assets/minecraft/models/block/my_cube.json

Custom geometry (elements)

Item Models

Simple flat item

Held item (in-hand model)

Two-layer item (colored like leather armor)

Custom model data overrides (1.21.4 and prior)

1.21.4+ Item Model (new format)

Blockstate Definitions

Simple block (no variants)

Facing block (4 rotations)

Random texture (multipart)

Multipart (slabs, fences, walls)

Textures

Animated texture MCMETA

GUI sprites (1.20.2+)

Sounds

assets/minecraft/sounds.json

Language Files

Fonts

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

OptiFine CIT (Custom Item Textures)

assets/minecraft/optifine/cit/my_sword.properties

Iris Shaders (Resource Pack Method)

Installation

Common Issues

Validator Script

References

Other skills for the same job

How to use it

`pack.mcmeta`

`assets/minecraft/models/block/my_cube.json`

`assets/minecraft/sounds.json`

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

`assets/minecraft/optifine/cit/my_sword.properties`