blockbench-modeling

name	blockbench-modeling
description	Create and edit 3D models in Blockbench using MCP tools. Use when building geometry with cubes, creating meshes, placing spheres/cylinders, editing vertices, extruding faces, or organizing models with groups. Covers both cube-based Minecraft modeling and freeform mesh editing.

Blockbench Modeling

Build 3D models using cubes and meshes in Blockbench.

Available Tools

Cube Tools

Tool	Purpose
place_cube	Create cubes with position, size, texture
modify_cube	Edit cube properties (position, rotation, UV, etc.)

Mesh Tools

Tool	Purpose
place_mesh	Create mesh with vertices
create_sphere	Create sphere mesh
create_cylinder	Create cylinder mesh
extrude_mesh	Extrude faces/edges/vertices
subdivide_mesh	Add geometry detail
select_mesh_elements	Select vertices/edges/faces
move_mesh_vertices	Move selected vertices
delete_mesh_elements	Remove geometry
merge_mesh_vertices	Weld nearby vertices
create_mesh_face	Create face from vertices
knife_tool	Cut edges into faces

Element Tools

Tool	Purpose
add_group	Create bone/group
list_outline	View model hierarchy
duplicate_element	Copy elements
rename_element	Rename elements
remove_element	Delete elements
find_elements_by_criteria	Query elements by name pattern, type, parent, size
select_all_of_type	Bulk-select cubes, meshes, or groups
filter_by_material	Find elements referencing a texture

Cube Modeling

Place a Cube

place_cube: elements=[{
  name: "body",
  from: [-4, 0, -2],
  to: [4, 12, 2]
}], faces=true  # Auto UV

Place Multiple Cubes

place_cube: elements=[
  {name: "head", from: [-4, 12, -4], to: [4, 20, 4]},
  {name: "arm_left", from: [4, 4, -1], to: [6, 12, 1]},
  {name: "arm_right", from: [-6, 4, -1], to: [-4, 12, 1]}
], group="body"

Modify Cube

modify_cube: id="body", rotation=[0, 45, 0], origin=[0, 6, 0]

Cube with Texture

place_cube: elements=[{name: "block", from: [0,0,0], to: [16,16,16]}],
  texture="stone", faces=true

Mesh Modeling

Create Sphere

create_sphere: elements=[{
  name: "ball",
  position: [0, 8, 0],
  diameter: 16,
  sides: 12
}]

Create Cylinder

create_cylinder: elements=[{
  name: "pillar",
  position: [0, 0, 0],
  diameter: 8,
  height: 24,
  sides: 12,
  capped: true
}]

Extrude Face

select_mesh_elements: mesh_id="pillar", mode="face", elements=["top_face"]
extrude_mesh: mesh_id="pillar", mode="faces", distance=4

Subdivide for Detail

subdivide_mesh: mesh_id="sphere", cuts=2

Move Vertices

select_mesh_elements: mesh_id="mesh1", mode="vertex", elements=["v1", "v2"]
move_mesh_vertices: offset=[0, 2, 0]

Merge Close Vertices

merge_mesh_vertices: mesh_id="mesh1", threshold=0.1

Knife Cut

knife_tool: mesh_id="cube_mesh", points=[
  {position: [0, 8, -4]},
  {position: [0, 8, 4]}
]

Organization

Create Group Hierarchy

add_group: name="root", origin=[0, 0, 0], rotation=[0, 0, 0]
add_group: name="body", parent="root", origin=[0, 12, 0]
add_group: name="head", parent="body", origin=[0, 24, 0]

Add Cubes to Groups

place_cube: elements=[{name: "torso", from: [-4, 12, -2], to: [4, 24, 2]}],
  group="body"

Duplicate Element

duplicate_element: id="arm_left", newName="arm_right", offset=[-8, 0, 0]

View Hierarchy

list_outline  # Returns all groups and elements

Selection & Filtering

Query the model without loading the full outline. These tools are read-only except select_all_of_type.

Find Elements by Criteria

Combine any of: regex name match, substring match, type, parent-group scope, cube size bounds, selection scope.

# All cubes under "body" named like "arm_*"
find_elements_by_criteria: type="cube", parent_group="body", name_pattern="^arm_"

# Small cubes (under 4 units on any axis) in the currently selected elements
find_elements_by_criteria: selected_only=true, max_size=[4, 4, 4]

# Groups whose name contains "hand" (case-insensitive)
find_elements_by_criteria: type="group", name_contains="hand"

Returns { count, truncated, matches: [{ uuid, name, type, parent }] }.

Select All of Type

# Replace selection with every cube in the project
select_all_of_type: type="cube"

# Add all meshes under "head" to the current selection
select_all_of_type: type="mesh", parent_group="head", add_to_selection=true

Filter by Material

Find every cube or mesh that references a specific texture. For cubes, the exact face keys are returned.

filter_by_material: texture="skin"
# → { texture, count, matches: [{ uuid, name, type: "cube", faces: ["north", "up"] }] }

Useful when refactoring textures: find all users before swapping or retiring a texture.

Common Patterns

Minecraft Character

# Create hierarchy
add_group: name="root", origin=[0, 0, 0]
add_group: name="body", parent="root", origin=[0, 24, 0]
add_group: name="head", parent="body", origin=[0, 24, 0]
add_group: name="arm_left", parent="body", origin=[5, 22, 0]
add_group: name="arm_right", parent="body", origin=[-5, 22, 0]
add_group: name="leg_left", parent="root", origin=[2, 12, 0]
add_group: name="leg_right", parent="root", origin=[-2, 12, 0]

# Add geometry
place_cube: elements=[{name: "head", from: [-4, 24, -4], to: [4, 32, 4]}], group="head"
place_cube: elements=[{name: "body", from: [-4, 12, -2], to: [4, 24, 2]}], group="body"
place_cube: elements=[{name: "arm", from: [-1, 0, -1], to: [1, 10, 1]}], group="arm_left"
place_cube: elements=[{name: "arm", from: [-1, 0, -1], to: [1, 10, 1]}], group="arm_right"
place_cube: elements=[{name: "leg", from: [-2, 0, -2], to: [2, 12, 2]}], group="leg_left"
place_cube: elements=[{name: "leg", from: [-2, 0, -2], to: [2, 12, 2]}], group="leg_right"

Smooth Organic Shape

create_sphere: elements=[{name: "base", position: [0, 8, 0], diameter: 16, sides: 16}]
subdivide_mesh: mesh_id="base", cuts=1
# Select and move vertices to shape
select_mesh_elements: mesh_id="base", mode="vertex"
move_mesh_vertices: offset=[0, 4, 0], vertices=["top_verts"]

Tips

• Use list_outline to see current model structure
• Use find_elements_by_criteria for targeted queries instead of filtering list_outline results client-side
• Set group origins at joint/pivot points for animation
• Use faces=true for auto UV mapping on cubes
• Create bone hierarchy before adding geometry
• Use duplicate_element with offset for symmetrical parts
• Mesh editing is more flexible but cubes are simpler for Minecraft-style models
• Before reworking a model, call save_checkpoint (history skill) so you can roll back with undo