Block predicate

This feature is exclusive to Java Edition.

A block predicate is a test for the state of a block at a given position in the world. They are used by placement modifiers in placed features, numerous configured features, and enchantments.

JSON Format

Block predicated are defined using the following format:

[NBT Compound / JSON Object]: a block predicate
- [String] type: The type of the block predicate. See Block predicate § Types for options.
- additional fields depending on [String] type. See Block predicate § Types.

Types

The following block predicate types exist:

true

Always matches, independent of the block.

[NBT Compound / JSON Object]: a block predicate
- [String] type: true

all_of

Combined multiple block predicates. Matches if all specified block predicates match.

[NBT Compound / JSON Object]: a block predicate
- [String] type: all_of
- [NBT List / JSON Array] predicates: (Can be empty) The child predicates.
  - [NBT Compound / JSON Object]: A block predicate.

any_of

Combined multiple block predicates. Matches if at least one of the specified block predicates matches.

[NBT Compound / JSON Object]: a block predicate
- [String] type: any_of
- [NBT List / JSON Array] predicates: (Can be empty) The child predicates.
  - [NBT Compound / JSON Object]: A block predicate.

not

Inverts a given block predicate. Matches if the specified other block predicate does not match.

[NBT Compound / JSON Object]: a block predicate
- [String] type: not
- [NBT Compound / JSON Object] predicate: The block predicate to invert.

has_sturdy_face

Checks if the block at the specified offset has a full block supporting surface in the specified direction.

[NBT Compound / JSON Object]: a block predicate
- [String] type: has_sturdy_face
- [NBT List / JSON Array] offset: (optional, defaults to [0,0,0]) A list of 3 integers specifying an [X, Y, Z] block position offset to check.
  - [Int]: Value between -16 and 16 (inclusive).
- [String] direction: The direction of the block to check if it is sturdy.

inside_world_bounds

Checks if the positions y-level (with specified offset) is within the height limits of the world.

[NBT Compound / JSON Object]: a block predicate
- [String] type: inside_world_bounds
- [NBT List / JSON Array] offset: (optional, defaults to [0,0,0]) A list of 3 integers specifying an [X, Y, Z] block position offset to check.
  - [Int]: Value between -16 and 16 (inclusive).

matching_block_tag

Checks if the block at the specified offset is in the given block tag.

[NBT Compound / JSON Object]: a block predicate
- [String] type: matching_block_tag
- [NBT List / JSON Array] offset: (optional, defaults to [0,0,0]) A list of 3 integers specifying an [X, Y, Z] block position offset to check.
- [String] tag: The block tag without # to check for.

matching_blocks

Checks if the block at the specified offset is one of the specified blocks.

[NBT Compound / JSON Object]: a block predicate
- [String] type: matching_blocks
- [NBT List / JSON Array] offset: (optional, defaults to [0,0,0]) A list of 3 integers specifying an [X, Y, Z] block position offset to check.
- [String][NBT List / JSON Array] blocks: Any number of block(s) (an [String] ID, or a [String] tag with #, or an [NBT List / JSON Array] array containing [String] IDs) that will match.

matching_fluids

Checks if the fluid at the specified offset is one of the specified fluid.

[NBT Compound / JSON Object]: a block predicate
- [String] type: matching_fluids
- [NBT List / JSON Array] offset: (optional, defaults to [0,0,0]) A list of 3 integers specifying an [X, Y, Z] block position offset to check.
- [String][NBT List / JSON Array] fluids: Any number of fluid(s) (an [String] ID, or a [String] tag with #, or an [NBT List / JSON Array] array containing [String] IDs) that will match.

replaceable

Checks if the block at the specified offset can be replaced by placing blocks.

[NBT Compound / JSON Object]: a block predicate
- [String] type: replaceable
- [NBT List / JSON Array] offset: (optional, defaults to [0,0,0]) A list of 3 integers specifying an [X, Y, Z] block position offset to check.
  - [Int]: Value between -16 and 16 (inclusive).

solid

Checks if the block at the specified offset is solid.

[NBT Compound / JSON Object]: a block predicate
- [String] type: solid
- [NBT List / JSON Array] offset: (optional, defaults to [0,0,0]) A list of 3 integers specifying an [X, Y, Z] block position offset to check.
  - [Int]: Value between -16 and 16 (inclusive).

would_survive

Checks if a specified block state is a valid placement at the given offset.

[NBT Compound / JSON Object]: a block predicate
- [String] type: would_survive
- [NBT List / JSON Array] offset: (optional, defaults to [0,0,0]) A list of 3 integers specifying an [X, Y, Z] block position offset to check.
  - [Int]: Value between -16 and 16 (inclusive).
- [NBT Compound / JSON Object] state: The blockstate to test.
  - Block state see Template:Nbt inherit/block state/template