Quote from orangejuice137»

I'm trying to detect if a player is standing still or moving. This command below is attempting to add 1 to a scoreboard "timer" when I'm standing still.

/execute as @a[nbt={Motion:[0.0,0.0,0.0]}] run scoreboard players add @s timer 1

As you probably could've guessed, this doesn't work. Even when I'm moving, it will still add 1.

For some odd reason, however, it stops when I'm sprinting and jumping (weird exception).

Can you guys help me out?

One reason the command behaves that way (apart from player motion being messed up as was mentioned) is because when you test for data within a list (values surrounded by square brackets), each element within the list you specify is checked within every element on the target.

For example, if you checked for "List:[1]" and the target had a list of "List:[3,2,1]", it would match because your specified value of "1" is compared with the target's values of "3", "2", and "1", and it matched the last value. Therefore your test of "Motion:[0.0,0.0,0.0]" is the exact same as testing "Motion:[0.0]".

But for whatever reason, the player's X and Z motion will be 0 even when moving normally, so the check for Motion:[0.0] will always find at least 1 element. Sprint-jumping causes the values to actually update, and no motion values are 0 at that point, so the check fails.

As for the objectives, you'd create them like so (prepended with "minecraft.custom:minecraft."):

/scoreboard objectives add jump minecraft.custom:minecraft.jump

It simply means unsorted, such that the order will be whatever it is internally.

Internally the sorting is based on load order, such as which chunks are accessed first. Each chunk has its own array of entities. For example, when a chunk is loaded, it loads entities in the order that they were saved to chunk files. You can manipulate the ordering by killing and summoning entities in a specific order in the same chunk.

However, this is not something you'll want to rely on because it could change in the future. The goal of "arbitrary" is to greatly increase performance by not using expensive sorting methods (which was not avoidable pre-1.13, as it would always sort by distance unless @r was used), so that's all you should really be using it for.

Quote from SquareEggs»

I didn't know that, why would they remove such a simple and useful command..

To elaborate further for this particular case: /testfor did not need to be used. If you're checking the location of a player with the selector in /testfor in order to teleport them elsewhere, then simply move the selector out of /testfor and into /tp. /testfor just serves as a redundant step.

The nested quotation marks will need to be escaped further (more backslashes). With no backslash, it will close the nested `Pages` string early and cause an NBT syntax error. With one backslash, it will close the `value` string of the text component early and cause a JSON syntax error.

The formula to determine the number of backslashes depending on the depth is: 2n+1 where n is the number of current backslashes. For example, the first depth is 1 backslash, while the next depth is 3 backslashes (then 7, then 15, and so on).

{\"text\":\"LittleBunnyRabb\",\"color\":\"dark_green\",\"clickEvent\":{\"action\":\"run_command\",\"value\":\"/tellraw @a {\\\"text\\\":\\\"Sleep?\\\"}\"}} 

Index

Generic info

1. Intro
2. Errors

File editing

3. Location

4. Referencing
5. Replacing default advancements

6. Editing

Shared data structures

7. JSON structure
8. Shared: range
9. Shared: location object
10. Shared: distance object
11. Shared: status effects object
12. Shared: item object
13. Shared: entity object
14. Shared: block object
15. Shared: damage object
16. Shared: damage flags object
17. Shared: death object

Customizing advancements

18. Criteria

19. Requirements
20. Display

21. Rewards
22. Tree display

Conclusion

23. Q&A
24. External links

Generic info

Intro

Errors

Game Output window

To open the Game Output window when launching the game, you must enable it in the "Settings" tab of the launcher.



This window will show the error and stacktrace explaining the issue.

Log files

If you no longer have the Game Output window open, you can check the output log. You can quickly access the Minecraft program files in the launcher by navigating to Launch Options -> + Add New, and clicking the "Go to folder" button:



From there, navigate to the /logs/latest.log file, which will contain the stacktrace. In this case, the error is stating that the advancement has a display, but is missing a description:

[07:02:59] [Server thread/ERROR]: Parsing error loading custom advancement custom:example
com.google.gson.JsonSyntaxException: Missing description
    at qe.a(SourceFile:447) ~[17w15a.jar:?]
    at r.a(SourceFile:66) ~[17w15a.jar:?]

[/pre]
[spoiler=Advancement(s)]
Paste advancement(s) here, along with filepath[/spoiler]
[spoiler=Error]
Paste error & stacktrace here[/spoiler]
[pre]

File editing

File location

Namespaces

The root folder that you create within the /advancements/ folder will be referred to as the "namespace". This is what separates collections of advancements, such as for different mods or maps. File/folder names must all be lowercase to circumvent issues with differing operating system file structures.

From the image example above, "skylinerwadvancements", "anothermod", and "minecraft" are the namespaces.

The "minecraft" namespace in particular should only be used to overwrite default advancements, such as with the intent to prevent them from working. Place any new advancements in a new namespace and not within "minecraft".

Referencing

[namespace]:[filepath/to/advancement]

Example, targeting the file /data/advancements/anothermod/challenges/kill_creepers.json:

anothermod:challenges/kill_creepers

By excluding the namespace, it will automatically assume it's meant to be "minecraft":

story/elytra = minecraft:story/elytra

Replacing default advancements

{
    "display": {
        "icon": {
            "item": "minecraft:elytra"
        },
        "title": "Learn to Fly"
    },
    "parent": "minecraft:story/enter_end_gateway",
    "criteria": {
        "elytra": {
            "trigger": "minecraft:inventory_changed",
            "conditions": {
                "items": [
                    {
                        "item": "minecraft:elytra",
                        "data": 1
                    }
                ]
            }
        }
    }
}

List of default advancements

The following is a list of default advancements. Be aware that this will dramatically change over time.

https://pastebin.com/L7G1RBdC

Editing

1. Click Save or Save As.
2. Set "Save as type" to "All files (*.*)".
3. Name your file and append the name with ".json".
4. Set "Encoding" to "UTF-8".
5. Save.

Image example:

2. Notepad++ is a great alternative to using plain Notepad. Instructions for saving a .json in UTF-8:

1. Change the encoding to either "UTF-8" or "UTF-8 without BOM" under the "Encoding" menu. See image below.
2. Click Save or Save As.
3. Set "Save as type" to "All files (*.*)".
4. Name your file and append the name with ".json".
5. Save.

Image example:

3. Atom has multiple platform support. Instructions for saving a .json in UTF-8:

1. Change the encoding to "UTF-8" under the "Select Encoding" menu. See image below.
2. Click Save or Save As.
3. Set "Save as type" to "All files (*.*)".
4. Name your file and append the name with ".json".
5. Save.

Image example:

Shared data structures

JSON Structure

{
    "criteria": {
        "custom_trigger_name": {
            "trigger": "namespace:trigger_name",
            "conditions": {
                "durability": 1,
                "durability": {"min":1,"max":1},
                "delta": 1,
                "delta": {"min":1,"max":1},
                "slots": {
                    "occupied": 1,
                    "occupied": {"min":1,"max":1},
                    "full": 1,
                    "full": {"min":1,"max":1},
                    "empty": 1,
                    "empty": {"min":1,"max":1}
                },
                "items": [
                    {
                        "item": "minecraft:stone",
                        "count": 1,
                        "count": {"min":1,"max":1},
                        "data": 1,
                        "data": {"min":1,"max":1},
                        "durability": 1,
                        "durability": {"min":1,"max":1},
                        "potion": "minecraft:invisibility",
                        "enchantments": [
                            {
                                "enchantment": "minecraft:sharpness",
                                "levels": 1,
                                "levels": {"min":1,"max":1}
                            }
                        ]
                    }
                ],
                "item": {
                    "item": "minecraft:stone",
                    "count": 1,
                    "count": {"min":1,"max":1},
                    "data": 1,
                    "data": {"min":1,"max":1},
                    "durability": 1,
                    "durability": {"min":1,"max":1},
                    "potion": "minecraft:invisibility",
                    "enchantments": [
                        {
                            "enchantment": "minecraft:sharpness",
                            "levels": 1,
                            "levels": {"min":1,"max":1}
                        }
                    ]
                },
                "levels": 1,
                "levels": {"min":1,"max":1},
                "recipe": "minecraft:chest",
                "position": {
                    "x": 1,
                    "x": {"min":1,"max":1},
                    "y": 1,
                    "y": {"min":1,"max":1},
                    "z": 1,
                    "z": {"min":1,"max":1}
                },
                "biome": "minecraft:void",
                "feature": "EndCity",
                "dimension": "overworld",
                "from": "overworld",
                "to": "overworld",
                "block": "minecraft:stone",
                "state": {
                    "state_name": "state_value"
                },
                "entity": {
                    "type": "minecraft:creeper",
                    "distance": 1,
                    "distance": {"min":1,"max":1}
                },
                "killing_blow": {
                    "bypasses_armor": true,
                    "bypasses_invulnerability": true,
                    "bypasses_magic": true,
                    "is_explosion": true,
                    "is_fire": true,
                    "is_magic": true,
                    "is_projectile": true,
                    "direct_entity": {
                        "type": "minecraft:creeper",
                        "distance": 1,
                        "distance": {"min":1,"max":1}
                    },
                    "source_entity": {
                        "type": "minecraft:creeper",
                        "distance": 1,
                        "distance": {"min":1,"max":1}
                    }
                },
                "distance": 1,
                "distance": {"min":1,"max":1},
                "parent": {
                    "type": "minecraft:creeper",
                    "distance": 1,
                    "distance": {"min":1,"max":1}
                },
                "partner": {
                    "type": "minecraft:creeper",
                    "distance": 1,
                    "distance": {"min":1,"max":1}
                }
                "child": {
                    "type": "minecraft:creeper",
                    "distance": 1,
                    "distance": {"min":1,"max":1}
                },
                "potion": "minecraft:invisibility",
                "level": 1,
                "level": {"min":1,"max":1},
                "damage": {
                    "dealt": 1,
                    "dealt": {"min":1,"max":1},
                    "taken": 1,
                    "taken": {"min":1,"max":1},
                    "blocked": true,
                    "type": {
                        "bypasses_armor": true,
                        "bypasses_invulnerability": true,
                        "bypasses_magic": true,
                        "is_explosion": true,
                        "is_fire": true,
                        "is_magic": true,
                        "is_projectile": true,
                        "direct_entity": {
                            "type": "minecraft:creeper",
                            "distance": 1,
                            "distance": {"min":1,"max":1}
                        },
                        "source_entity": {
                            "type": "minecraft:creeper",
                            "distance": 1,
                            "distance": {"min":1,"max":1}
                        }
                    },
                    "source_entity": {
                        "type": "minecraft:creeper",
                        "distance": 1,
                        "distance": {"min":1,"max":1}
                    }
                }
            }
        }
    },
    "requirements": [["generic_trigger_name"]],
    "parent": "namespace:path/to/parent_advancement",
    "display": {
        "icon": {
            "item": "minecraft:stone_pickaxe",
            "data": 0
        },
        "title": "Display title",
        "description": "Display description",
        "frame": "task",
        "background": "minecraft:path/to/texture.png"
    },
    "rewards": {
        "recipes": ["namespace:path/to/recipe"],
        "loot": ["namespace:path/to/loot_table"],
        "experience": 1,
        "commands": ["/say Command to run upon completion"]
    }
}

Shared: range

"occupied": 3

To check between two values, the range must be specified as an object containing "min" and "max" numbers. The following checks if the compared value is between 1 and 3.

"occupied": {
    "min": 1,
    "max": 3
}

You can alternatively specify only the minmum or only the maximum, which will ignore a check for the opposing limiter. For example, the following checks if there are at least 3 occupied slots. The player's inventory could have 7 occupied slots and they will still match.

"occupied": {
    "min": 3
}

Versus the opposite, where the following checks if there are at most 2 occupied slots. The player's inventory could have 0 occupied slots and they will still match.

"occupied": {
    "max": 2
}

Shared: location object

"location_object": {
    "position": {
        "y": {
            "max": 62.0
        }
    }
}

2. "biome"

The "biome" string specifies the name ID of the biome that the player must stand within. You can find a list of name IDs for biomes here. The following checks if the player has visited the "minecraft:desert" biome.

"location_object": {
    "biome": "minecraft:desert"
}

3. "feature"

The "feature" string specifies the name ID of a structure. The player must be standing within the bounding box of that structure to be detected. The following checks if the player is inside an "EndCity" structure.

"location_object": {
    "feature": "EndCity"
}

4. "dimension"

The "dimension" string specifies the name ID of a dimension to find the player in. Accepted values are "overworld", "the_nether", and "the_end". The following checks if the player is anywhere in the nether.

"location_object": {
    "dimension": "the_nether"
}

Shared: distance object

"distance_object": {
    "x": {
        "max": 40.0
    }
}

2. "absolute"

The "absolute" range checks if the player is within a number of blocks on all axes. You would use this instead of "x/y/z" if all axes are uniform. The following checks if the player is outside a 5-block range of an origin.

"distance_object": {
    "absolute": {
        "min": 5.0
    }
}

3. "horizontal"

The "horizontal" range checks if the player is within a number of blocks on the X and Z axes, ignoring the Y axis. The following checks if the player is withn a 10-block range of an origin, but only on the X and Z axes.

"distance_object": {
    "horizontal": {
        "max": 10.0
    }
}

Shared: status effects object

"effects_object": {
    "minecraft:levitation": {
        "amplifier": {
            "min": 10
        }
    }
}

2. "duration"

The "duration" range checks the remaining duration in ticks of the specified effect. The following checks if the effect has at least 15 seconds (300 ticks) remaining.

"effects_object": {
    "minecraft:levitation": {
        "duration": {
            "max": 300
        }
    }
}

3. "ambient"

The "ambient" boolean checks if the effect has the "ambient" flag set to true.

"effects_object": {
    "minecraft:levitation": {
        "ambient": true
    }
}

4. "visible"

The "visible" boolean checks if the effect has the "visible" flag set to true.

"effects_object": {
    "minecraft:levitation": {
        "visible": true
    }
}

Shared: item object

"item_object": {
    "item": "minecraft:redstone"
}

2. "data"

The "data" integer specifies a metadata of the item. The following checks if the item is a polished granite block.

"item_object": {
    "item": "minecraft:stone",
    "data": 2
}

3. "durability

The "data" range specifies the remaining durability of an item. The following checks if the item has 400 or more durability remaining.

"item_object": {
    "durability": {
        "min": 400
    }
}

4. "count"

The "count" range specifies the number of items in a single stack. This cannot be used to check the number of items across the inventory as a whole. The following checks if the item has 16 or more in its stack.

"item_object": {
    "count": {
        "min": 16
    }
}

5. "potion"

The "potion" string specifies the default brewed potion ID that the item must contain, specified in the Potion NBT string. The wiki contains a list of those IDs here.

"item_object": {
    "potion": "minecraft:invisibility"
}

The item does not have to be a potion. As long as the item has the Potion NBT string, it will match:

/give @p minecraft:stone 1 0 {Potion:"minecraft:invisibility"}

6. "enchantments"

The "enchantments" list checks the item's enchantments (whether in the ench NBT list for all items excluding books, or the StoredEnchantments NBT list for only books) for matching data. If only an empty object is specified, the player's inventory is checked for any enchanted items.

"item_object": {
    "enchantments": [
        {
            
        }
    ]
}

The "enchantment" string will specify the enchantment ID to look for. The following checks the item for the Sharpness enchantment.

"item_object": {
    "enchantments": [
        {
            "enchantment": "minecraft:sharpness"
        }
    ]
}

The "levels" range will specify the range of levels to find for an enchantment. The following checks if the player has any enchantments level 3 or higher.

"item_object": {
    "enchantments": [
        {
            "levels": {
                "min": 3
            }
        }
    ]
}

And combining it with an ID, the following checks if the player has Sharpness 5.

"item_object": {
    "enchantments": [
        {
            "enchantment": "minecraft:sharpness"
            "levels": 5
        }
    ]
}

7. "nbt"

The "nbt" string compares the raw NBT input to the item's NBT data. This raw data starts within the "tag" compound of the item format and must be surrounded by curly brackets. The following checks if the item has a specific display name.

"item_object": {
    "nbt": "{display:{Name:\"Test\"}}"
}

Shared: entity object

"entity_object": {
    "type": "minecraft:creeper"
}

2. "distance"

The "distance" distance object specifies the distance between the advancement-earning player and an entity's origin. The following checks if the player is within 10 blocks of the entity.

"entity_object": {
    "distance": {
        "absolute": {
            "max": 10
        }
    }
}

3. "location"

The "location" location object checks data concerning the entity's location in the world. The following checks if the entity is in the desert biome.

"entity_object": {
    "location": {
        "biome": "minecraft:desert"
    }
}

4. "effects"

The "effects" status effects object checks data concerning the entity's status effects. The following checks if the entity has Speed 2.

"entity_object": {
    "effects": {
        "minecraft:speed": {
            "amplifier": 2
        }
    }
}

5. "nbt"

The "nbt" string compares the raw NBT input to the entity's NBT data. This raw data starts within the root of the entity format and must be surrounded by curly brackets. The following checks if the entity has a specific tag within its "Tags" list.

"entity_object": {
    "nbt": "{Tags:[\"findme\"]}"
}

Shared: block object

"block_object": {
    "block": "minecraft:tallgrass"
}

2. "state"

The "state" object contains a list of custom keys, much like "criteria" does. The names for these keys will correspond to the blockstate name you want to detect, and the value corresponds to possible values for that blockstate. For "minecraft:tallgrass", the "type" blockstate specifies which of the tallgrass blocks it is. The "block" string must be specified to use this condition. The following checks if the tallgrass is a fern.

"block_object": {
    "block": "minecraft:tallgrass",
    "state": {
        "type": "fern"
    }
}

Shared: damage object

"damage_object": {
    "dealt": {
        "min": 4.0
    },
    "source_entity": {
        "type": "minecraft:arrow"
    }
}

2. "taken"

A range checking the incoming damage after damage reduction. For example, the following checks if the resulting damage after reductions was at least 5.0.

"damage_object": {
    "taken": {
        "min": 5.0
    }
}

3. "blocked"

Checks if the incoming damage was successfully blocked, provided that the "damage_flags_object.bypasses_armor" ("unblockable") flag isn't true. The following checks if the player failed to block a skeleton's attack (either by an arrow or melee weapon).

"damage_object": {
    "blocked": false,
    "source_entity": {
        "type": "minecraft:skeleton"
    }
}

4. "type"

A damage flag object that checks various flags about the damage. The following checks if the damage was a projectile caused by a skeleton (though does not necessarily mean the direct cause of the damage was an arrow).

"damage_object": {
    "type": {
        "is_projectile": true
    },
    "source_entity": {
        "type": "minecraft:skeleton"
    }
}

5. "source_entity"

An entity object that checks information about either the entity hit or the entity dealing the damage. Note that for players being the source entity, the nested "type" string can essentially only be "minecraft:player". The following checks if a skeleton was at least 10 blocks away when it hit the player.

"damage_object": {
    "source_entity": {
        "type": "minecraft:skeleton",
        "distance": {
            "min": 10
        }
    }
}

Shared: damage flags object

"damage_object": {
    "bypasses_armor": true
}

2. "bypasses_invulnerability"

Checks if the damage source can inflict damage on creative mode players. This is true for: void damage. The following checks if the incoming damage is not caused by the Void or /kill.

"damage_object": {
    "bypasses_invulnerability": false
}

3. "bypasses_magic"

Checks the "damageIsAbsolute" flag for the incoming damage. This is true for: starvation. The following checks if the player is taking starvation damage.

"damage_object": {
    "bypasses_magic": true
}

4. "is_explosion"

Checks the "explosion" flag for the incoming damage. This is true for: creepers, ender crystals, TNT, Minecart TNT, ghast fireballs, beds, the wither, and wither skulls. The following checks if the "explosion" flag is true.

"damage_object": {
    "explosion": true
}

5. "is_fire"

Checks the "fire" flag for the incoming damage. This is true for: standing in a fire block, being on fire, standing on magma, standing in lava, ghast fireballs, and blaze fireballs. The following checks if the player is not taking damage from fire sources.

"damage_object": {
    "is_fire": false
}

6. "is_magic"

Checks the "magicDamage" flag for the incoming damage. This is true for: thorns, Instant Damage effect, Poison effect, part of Guardian laser damage, evocation fangs, and un-owned wither skulls (via /summon). The following checks if the incoming damage is flagged as magic damage.

"damage": {
    "is_magic": true
}

7. "is_projectile"

Checks the "projectile" flag for the incoming damage. This is true for: arrows, ghast fireballs, blaze fireballs, enderpearls, eggs, snowballs, shulker bullets, and llama spit. The following checks if the incoming damage is specifically not a projectile.

"damage": {
    "is_projectile": false
}

8. "source_entity"

An entity object that specifies the "owner" of the damage. For example, if the player was hit by an arrow shot by a skeleton, the skeleton would be the "source entity". The damage object already makes use of this check, so it is pointless to specify a source entity twice. This particular check is still useful for triggers that only use a damage flags object rather than a damage object.

"damage": {
    "source_entity": {
        "type": "minecraft:skeleton"
    }
}

9. "direct_entity"

An entity object that specifies the direct cause of the damage. For example, if the player was hit by an arrow shot by a skeleton, the arrow would be the "direct entity". The following ensures the player was hit by an arrow shot by a skeleton.

"damage": {
    "direct_entity": {
        "type": "minecraft:arrow"
    },
    "source_entity": {
        "type": "minecraft:skeleton"
    }
}

Shared: death object

"death_object": {
    "entity": {
        "type": "minecraft:creeper"
    }
}

2. "killing_blow"

A damage flags object that contains damage flags about the killing blow against the dead entity. Be aware that this is not the damage object, so the options from that object are unavailable. The following checks if the entity had died due to an explosion.

"death_object": {
    "killing_blow": {
        "is_explosion": true
    }
}

Customizing advancements

Criteria

{
    "criteria": {
        "custom_test_name": {
            "trigger": "minecraft:bred_animals"
        },
        "take_damage": {
            "trigger": "minecraft:entity_hurt_player"
        }
    }
}

While the following advancement is granted provided either the "custom_test_name" and "take_damage" criteria succeeds. See the Requirements section for more details.

{
    "criteria": {
        "custom_test_name": {
            "trigger": "minecraft:bred_animals"
        },
        "take_damage": {
            "trigger": "minecraft:entity_hurt_player"
        }
    },
    "requirements": [["custom_test_name"], ["take_damage"]]
}

The custom criteria names are local to that file and cannot be referred to in other files.

Triggers

Go to list of triggers

Processing order of triggers

The following timeline describes the order in which specific triggers activate in each game tick. This can be useful when running a function as a reward. For example, if you needed to run commands before entities are processed (and after command blocks are processed), the "minecraft:tick" trigger will do so. If you needed to run commands after entities are processed, you would use the "gameLoopFunction" gamerule to run the necessary function.

Requirements

{
    "criteria": {
        "trigger_1": {
            "trigger": "minecraft:entity_hurt_player"
        },
        "trigger_2": {
            "trigger": "minecraft:used_ender_eye"
        }
    },
    "requirements": [
        ["trigger_1"], ["trigger_2"]
    ]
}

Both "trigger_1" and "trigger_2" criteria must be fulfilled before the advancement can be granted. Since that would be the case without "requirements", it is not necessary to use it here. Using logical operators, this can be viewed as:

"trigger_1" && "trigger_2"

Modifying the requirements list slightly, which joins "trigger_2" with "trigger_1":

{
    "criteria": {
        "trigger_1": {
            "trigger": "minecraft:entity_hurt_player"
        },
        "trigger_2": {
            "trigger": "minecraft:used_ender_eye"
        }
    },
    "requirements": [
        ["trigger_1", "trigger_2"]
    ]
}

Now either "trigger_1" or "trigger_2" must be completed to be granted the advancement. Using logical operators, this can be viewed as:

"trigger_1" || "trigger_2"

{
    "criteria": {
        "trigger_1": {
            "trigger": "minecraft:entity_hurt_player"
        },
        "trigger_2": {
            "trigger": "minecraft:used_ender_eye"
        },
        "trigger_3": {
            "trigger": "minecraft:player_killed_entity"
        }
    },
    "requirements": [
        ["trigger_1"],
        ["trigger_2", "trigger_3"]
    ]
}

The advancement is granted if the "trigger_1" criterion is met, while either "trigger_2" and "trigger_3" are also met. If only "trigger_1" is completed, the advancement is not granted. Using logical operators, this can be viewed as:

"trigger_1" && ("trigger_2" || "trigger_3")

And modifying the requirements slightly:

{
    "criteria": {
        "trigger_1": {
            "trigger": "minecraft:entity_hurt_player"
        },
        "trigger_2": {
            "trigger": "minecraft:used_ender_eye"
        },
        "trigger_3": {
            "trigger": "minecraft:player_killed_entity"
        }
    },
    "requirements": [
        ["trigger_1", "trigger_2", "trigger_3"]
    ]
}

The advancement is granted if any of the criteria are met. Using logical operators, this can be viewed as:

"trigger_1" || "trigger_2" || "trigger_3"

Display

Title, description, & icon

When the "display" object exists, the "title", "description", and "icon" tags must be specified. The background for the icon for each advancement will range from gray to red depending on the number of criteria fulfilled in that advancement.

1. "title"

The title can either be a simple string or a text component object. This title is shown in the "Advancements" menu when hovering over the icon, as well as in the popup notification when completing the advancement.

Given the following advancement, which uses a simple string for the title:

{
    "display": {
        "title": "Stew",
        "description": "",
        "icon": {
            "item": "minecraft:mushroom_stew"
        },
        "background": "minecraft:textures/gui/advancements/backgrounds/stone.png"
    },
    "criteria": {
        "trigger_1": {
            "trigger": "minecraft:location"
        }
    }
}

This will display as:



Or you can specify formatting for the text using the text component (note that many text component features are unavailable, such as selectors, scores, and event listeners):

{
    "display": {
        "title": {"text":"Stew","obfuscated":true},
        "description": "",
        "icon": {
            "item": "minecraft:mushroom_stew"
        },
        "background": "minecraft:textures/gui/advancements/backgrounds/stone.png"
    },
    "criteria": {
        "trigger_1": {
            "trigger": "minecraft:location"
        }
    }
}

This will display as:



2. "description"

The description can either be a simple string or a text component object. This description is shown in the "Advancements" menu when hovering over the icon, but not in the popup notification when completing the advancement. The description can be blank for no description to appear, but the tag itself must still exist.

Given the following advancement, which uses a simple string for the description:

{
    "display": {
        "icon": {
            "item": "minecraft:elytra"
        },
        "title": "Learn to Fly",
        "description": "Learn how to fly using a new pair of elytra.",
        "background": "minecraft:textures/gui/advancements/backgrounds/stone.png"
    },
    "criteria": {
        "elytra": {
            "trigger": "minecraft:inventory_changed",
            "conditions": {
                "items": [
                    {
                        "item": "minecraft:elytra",
                        "data": 1
                    }
                ]
            }
        }
    }
}

This will display as:



Or you can specify formatting for the text using the text component (note that many text component features are unavailable, such as selectors, scores, and event listeners):

{
    "display": {
        "icon": {
            "item": "minecraft:elytra"
        },
        "title": "Learn to Fly",
        "description": {"text":"Learn how to fly using a new pair of elytra.","italic":true},
        "background": "minecraft:textures/gui/advancements/backgrounds/stone.png"
    },
    "criteria": {
        "elytra": {
            "trigger": "minecraft:inventory_changed",
            "conditions": {
                "items": [
                    {
                        "item": "minecraft:elytra",
                        "data": 1
                    }
                ]
            }
        }
    }
}

This will display as:



3. "icon"

The "icon" object holds a required item ID and an optional metadata value of the item. This icon is shown in the "Advancements" menu, as well as in the popup notification when completing the advancement. The following icon specifies red wool

"icon": {
    "item": "minecraft:wool",
    "data": 14
}

Background

The "background" is an optional string for all advancements, but is only used by "root" advancements (i.e. when no parent is defined). This is the background that appears behind all of the icons. The value is a resource location to any image within a resource pack. For example, the following advancement will display a tiled gold block background, coming from the default block texture:

{
    "display": {
        "title": "Stew",
        "description": "",
        "icon": {
            "item": "minecraft:mushroom_stew"
        },
        "background": "minecraft:textures/blocks/gold_block.png"
    },
    "criteria": {
        "trigger_1": {
            "trigger": "minecraft:location"
        }
    }
}

Image of the result:

Frame

An optional "frame" string modifies the border shape around the icon, accepting one of three possible values: "task", "challenge", and "goal". When not specified, it will default to "task".

The following advancement makes use of the "challenge" frame.

{
    "display": {
        "title": "Stew",
        "description": "",
        "icon": {
            "item": "minecraft:mushroom_stew"
        },
        "background": "minecraft:textures/blocks/gold_block.png",
        "frame": "challenge"
    },
    "criteria": {
        "trigger_1": {
            "trigger": "minecraft:location"
        }
    }
}

The following advancement makes use of the "goal" frame.

{
    "display": {
        "title": "Stew",
        "description": "",
        "icon": {
            "item": "minecraft:mushroom_stew"
        },
        "background": "minecraft:textures/blocks/gold_block.png",
        "frame": "goal"
    },
    "criteria": {
        "trigger_1": {
            "trigger": "minecraft:location"
        }
    }
}

Show toast

An optional "show_toast" boolean can be specified in order to prevent the popup notification in the upper right-hand corner of the screen from appearing when the player fulfills an advancement. It defaults to true, and setting it to false will hide the popup.

{
    "display": {
        "title": "Stew",
        "description": "",
        "icon": {
            "item": "minecraft:stone"
        },
        "background": "minecraft:textures/blocks/gold_block.png",
        "show_toast": false
    },
    "criteria": {
        "trigger_1": {
            "trigger": "minecraft:tick"
        }
    }
}

Announce to chat

An optional "announce_to_chat" boolean can be specified in order to prevent a chat message from being sent telling all players that somebody fulfilled an advancement. It defaults to true, and setting it to false will prevent chat messages from being sent.

{
    "display": {
        "title": "Stew",
        "description": "",
        "icon": {
            "item": "minecraft:stone"
        },
        "background": "minecraft:textures/blocks/gold_block.png",
        "announce_to_chat": false
    },
    "criteria": {
        "trigger_1": {
            "trigger": "minecraft:tick"
        }
    }
}

The announceAdvancements gamerule can globally disable fulfillment messages, overriding the value of "announce_to_chat" for individual advancements.

/gamerule announceAdvancements false

Hidden

An optional "hidden" boolean can be specified in order to prevent child advancements from displaying in the "Advancements" menu until they are completed.

{
    "display": {
        "title": "Stew",
        "description": "",
        "icon": {
            "item": "minecraft:stone"
        },
        "background": "minecraft:textures/blocks/gold_block.png",
        "announce_to_chat": false,
        "hidden": true
    },
    "criteria": {
        "trigger_1": {
            "trigger": "minecraft:impossible"
        }
    }
}

Rewards

"recipes"

This list specifies multiple recipes to unlock for the player upon completing the advancement. The following advancement unlocks the "minecraft:redstone" and "minecraft:ladder" recipes together.

{
    "criteria": {
        "custom_test_name": {
            "trigger": "minecraft:entity_hurt_player"
        }
    },
    "rewards": {
        "recipes": ["minecraft:redstone", "minecraft:ladder"]
    }
}

"loot"

This list specifies multiple loot tables to process, providing the player with the resulting item(s). The following advancement provides players with items from "minecraft:entities/creeper" and "minecraft:chests/simple_dungeon".

{
    "criteria": {
        "custom_test_name": {
            "trigger": "minecraft:entity_hurt_player"
        }
    },
    "rewards": {
        "loot": ["minecraft:entities/creeper", "minecraft:chests/simple_dungeon"]
    }
}

"experience"

This number (not range) specifies the amount of experience (not levels) to reward the player with.

{
    "criteria": {
        "custom_test_name": {
            "trigger": "minecraft:entity_hurt_player"
        }
    },
    "rewards": {
        "experience": 500
    }
}

"function"

This string specifies a single function file to run, with the value being the resource location to that function. The player will be considered the command sender and CommandStats trigger target, which means sender bias (such as from "@s") will always target that player, and that player will trigger their own stored CommandStats. Each command will run in the specified order in the function. If the advancement is granted via command block, all of the listed commands will execute immediately, allowing other command blocks further in the chain to run based off of the results of the advancement's function being run (although you do not need to use advancements for this if focusing on functions).

{
    "criteria": {
        "custom_test_name": {
            "trigger": "minecraft:entity_hurt_player"
        }
    },
    "rewards": {
        "function": "path:to/function"
    }
}

{
    "criteria": {
        "custom_test_name": {
            "trigger": "minecraft:entity_hurt_player"
        }
    },
    "rewards": {
        "recipes": ["minecraft:redstone", "minecraft:ladder"],
        "loot": ["minecraft:entities/creeper", "minecraft:chests/simple_dungeon"],
        "experience": 500,
        "function": "path:to/function"
    }
}

Tree display

Root

A root advancement will be one without a parent defined. If a root has a display, it will be the left-most icon in the tree. If a root does not have a display, a tab in the "Advancements" menu will not be shown, effectively hiding all branches in the tree. The popup notification for branches will be displayed even in that case, allowing you to show the player custom notifications without having to have a tab in the "Advancements" menu.

A root can also control the background of the tab.

The following is a proper root that will be shown in the menu, as it has both a display and no parent:

{
    "display": {
        "icon": {
            "item": "minecraft:diamond"
        },
        "title": "A Root",
        "description": "The root of this tree.",
        "background": "minecraft:textures/gui/advancements/backgrounds/stone.png"
    },
    "criteria": {
        "impossible": {
            "trigger": "minecraft:impossible"
        }
    }
}

While the following is an invisible root, as it has neither a display nor a parent:

{
    "criteria": {
        "impossible": {
            "trigger": "minecraft:impossible"
        }
    }
}

Branches

A branch is defined by having a "parent" string. The parent specifies the resource location of another advancement, where the branch visually extends from the parent. Note that the parent does not actually need to be completed in order for the branch to be completed.

The visual structure of the tree will be automatically generated.

For example, the following set of advancements defines a root and two branches, where the branches are direct descendents of the root:

/custom/root.json

{
    "display": {
        "icon": {
            "item": "minecraft:sapling"
        },
        "title": "A Root",
        "description": "The root of this tree.",
        "background": "minecraft:textures/gui/advancements/backgrounds/stone.png"
    },
    "criteria": {
        "auto": {
            "trigger": "minecraft:location"
        }
    }
}

/custom/branch_a.json

{
    "display": {
        "icon": {
            "item": "minecraft:stick"
        },
        "title": "Branch 1",
        "description": "One branch of the tree."
    },
    "parent": "custom:root",
    "criteria": {
        "auto": {
            "trigger": "minecraft:location"
        }
    }
}

/custom/branch_b.json

{
    "display": {
        "icon": {
            "item": "minecraft:blaze_rod"
        },
        "title": "Branch 2",
        "description": "Another branch of the tree."
    },
    "parent": "custom:root",
    "criteria": {
        "auto": {
            "trigger": "minecraft:location"
        }
    }
}

Visual:



Changing /custom/branch_b.json to the following will cause it to branch off of "custom:branch_a" rather than the root:

{
    "display": {
        "icon": {
            "item": "minecraft:blaze_rod"
        },
        "title": "Branch 2",
        "description": "Another branch of the tree."
    },
    "parent": "custom:branch_a",
    "criteria": {
        "auto": {
            "trigger": "minecraft:location"
        }
    }
}

Which would then show as a direct line of branches:



Since you can have multiple branches per parent, complex trees can be created. The following image is a segment from the default "story" tab for vanilla Minecraft, showing complex connections between branches:

Conclusion

Q&A

External links

Index

Generic info

1. Intro
2. Errors
3. JSON Structure
4. Unicode & escape sequences

In-game features

5. /tellraw
6. /title
7. Books
8. Signs
9. Advancements

Text component

10. Text input

11. Text styling

12. Event listeners

13. Adding text

Additional usage info

14. Inheritance
15. Senders & origins

16. /trigger

Conclusion

17. Q&A
18. External links
19. Conclusion

Generic info

Intro

Errors

[spoiler]Insert command here[/spoiler]

You can check for valid JSON using a generic validator such as JSONLint.

JSON structure

{
    "text": "",
    "translate": "",
    "with": [],
    "score": {
        "name": "",
        "objective": "",
        "value": ""
    },
    "selector": "",
    "keybind": "",
    "color": "",
    "bold": false,
    "italic": false,
    "underlined": false,
    "strikethrough": false,
    "obfuscated": false,
    "insertion": "",
    "clickEvent": {
        "action": "",
        "value": ""
    },
    "hoverEvent": {
        "action": "",
        "value": ""
    },
    "extra": []
}

Unicode & escape sequences

/tellraw @a {"text":"\u00B6"}

\n

"Newline" character, pushing text to the next line. While with signs it can be used, the text pushed to the next line will not be visible.

/tellraw @a ["Line 1\nLine 2"]

\" and \' and \\

Allows the usage of quotation marks nested within quotation marks, such as NBT data for various click/hover events, as well as backslashes as literal characters rather than as an escape sequence.

/tellraw @a ["This text is \"quoted\". Backslash: \\"]

Note that for nested quotes, deeper-nested quotation marks will need to be escaped further. The formula to obtain the number of backslashes needed is (2 * [current backslashes]) + 1. For example, if a quotation mark is needed as a literal value, but is already inside a set of quotes that has 1 backslash, 3 backslashes are needed in order to use the quotation marks:

/summon Creeper ~ ~1 ~ {CustomName:"the \"quoted\" text"}

/tellraw @a {"text":"Click","clickEvent":{"action":"run_command","value":"/testfor @e[type=Creeper] {CustomName:\"the \\\"quoted\\\" text\"}"}}

The next depth would be 7, then 15, and so on.

\t and \b and \f and \r

None of these escape characters can be used with the text component.

In-game features

/tellraw

/tellraw [player] [text component]

/tellraw @a {"text":"Hello","color":"red","italic":true}

Unavailable features:

1. "open_file" click event.
2. "change_page" click event.

/title

/title [player] [title|subtitle] [text component]

/title @a subtitle {"text":"The smaller subtitle","color":"red","italic":true}
/title @a title {"text":"The larger title","color":"red","italic":true}

Unavailable features:

1. All event listeners.

Books

/give @p minecraft:written_book 1 0 {title:"",author:"",pages:["{\"text\":\"Page 1\",\"italic\":true}"]}

Unavailable features:

1. insertion event listener.
2. open_file click event.
3. suggest_command click event.

Signs

/setblock ~ ~1 ~ minecraft:standing_sign 0 replace {Text1:"[\"Top text\"]",Text2:"[\"\"]",Text3:"[\"\"]",Text4:"[\"Bottom text\"]"}

Unavailable features:

1. insertion event listener.
2. open_file click event.
3. open_url click event.
4. suggest_command click event.
5. change_page click event.
6. All hover events.

Advancements

{
    "display": {
        "title": {"text":"This is the title.","color":"blue"},
        "description": {"translate":"custom.locale.key","with":[{"keybind":"key.inventory"}]},
        "icon": {
            "item": "minecraft:crafting_table"
        }
    },
    "criteria": {
        "custom_test_name": {
            "trigger": "minecraft:impossible"
        }
    }
}

Unavailable features:

1. Score text.
1. Selector text.
2. All event listeners.

Text component

Text input

/tellraw @a {"text":""}

Alternatively, if within an array of text components (such as from instantiation or via extra), a lone string will act as text.

/tellraw @a ["String 1",{"text":"","extra":["String 2"]}]

"text"

Basic text with no parsing other than escape sequence support. Target selectors are not parsed using this option.

/tellraw @a {"text":"String"}

If specifying a lone string within an array of text components (such as from instantiation or via extra), the input will be parsed as the text option.

/tellraw @a ["String 1","String 2"]
/tellraw @a {"text":"String 1","extra":["String 2"]}

"translate"

Sends input through the translation parser, useful for multi-lingual support. The input is expected to be the language key (e.g. gui.toTitle), but if the key is invalid it will be parsed as though it were the key's value instead. The output shown will be dependent on the player's language setting, unless the key is invalid.

/tellraw @a {"translate":"gui.toTitle"}

Example, showing that invalid key results in input being parsed as output.

/tellraw @a {"translate":"Text inserted here"}

Conversion flags & "with"

Minecraft's language files support the usage of several conversion flags, which are placeholders for text. For example:

commands.generic.entity.invalidType=Entity type '%s' is invalid

%s is the placeholder, which is text to be inserted at a later point. While the language files support the use of a handful of different conversion flags, all flags are converted to %s or %#$s. See here for a more in-depth explanation of placeholders, but be aware that Minecraft implements them manually and thus not all are available.

The with array will hold the extra data to be inserted. Example, where the %s placeholder is replaced with "Creeper":

/tellraw @a {"translate":"commands.generic.entity.invalidType","with":["Creeper"]}

Conversion flags are also supported when specifying an invalid key, but be aware that the game is expecting only %s or %#$s. No other conversion flag will work for those cases.

/tellraw @a {"translate":"Insert a %s here.","with":["STRING"]}

custom.key = Insert %s and %s, followed by %s.

/tellraw @a {"translate":"custom.key","with":["STRING1", "STRING2"]}

Output = Insert STRING1 and STRING2, followed by .

custom.key = Insert %1$s and %2$s, followed by %1$s and %s.

/tellraw @a {"translate":"custom.key","with":["STRING1", "STRING2"]}

Output = Insert STRING1 and STRING2, followed by STRING1 and STRING1.

"with" & text components

The records inside with may also be text components. Availability will vary between in-game features, as usual. For example, the following replaces %s with a parsed target selector:

/tellraw @a {"translate":"Nearest player: %s","with":[{"selector":"@p"}]}

"score"

Displays the value of a score based on a playerscore on the scoreboard. The score object holds three keys: name, objective, and value.

A bug (see MC-56373) currently prevents full usage within hover events ("value" does work).

"name" is the name of the player stored on the scoreboard, which may be a "fake" player. It can also be a target selector that must resolve to 1 target, and may target non-player entities. With a book, /tellraw, or /title, using the wildcard * in place of a name/selector will cause all players will see their own score in the specified objective. Signs cannot use the wildcard.

"objective" is the objective to find the player's score from.

"value" stores the processed value so that the score does not need to be re-evaluated. If defined, this value is used instead of a processed score.

Example, where all players are shown the score of the nearest player in the "TEST" objective:

/tellraw @a {"score":{"name":"@p","objective":"TEST"}}

Example, where all players will see their own score in the "TEST" objective:

/tellraw @a {"score":{"name":"*","objective":"TEST"}}

Example, where a score is not processed due to value being present and will instead display "hello":

/tellraw @a {"score":{"name":"@p","objective":"TEST","value":"hello"}}

"selector"

Processes a target selector into a pre-formatted set of discovered names, complete with event listeners where applicable. Multiple targets may be obtained, with commas separating each one and a final "and" for the last target.

The resulting formatting cannot be overwritten. This includes all styling from team prefixes, insertion event for entity & player names, clickEvents for player names, and hoverEvents for entity & player names.

A bug (see MC-56373) prevents it from working in hover events.

Example, assuming there are 3 creepers:

/tellraw @a {"selector":"@e[type=Creeper]"}

"keybind"

Shows the player their corresponding key for a keybind. The following is a list of valid keybinds:

Example, showing the player their key for dropping an item (defaulting to Q):

/tellraw @a {"keybind":"key.drop"}

Text styling

"color"

Choose from a set of pre-determined colors that will be applied to the text. Defaults to "white". List of colors and their IDs:



Example, where the text is colored "red":

/tellraw @a {"text":"Hello","color":"red"}

"reset" may be used to reset the color to default.

/tellraw @a {"text":"Hello","color":"red","extra":[{"text":" there","color":"reset"}]}

"bold"

Boolean; increases text thickness. Defaults to "false".

/tellraw @a {"text":"Hello","bold":true}

"italic"

Boolean; emphasises text. Defaults to "false".

/tellraw @a {"text":"Hello","italic":true}

"underlined"

Boolean; underlines text. Defaults to "false".

/tellraw @a {"text":"Hello","underlined":true}

"strikethrough"

Boolean; adds a strikethrough in the middle of text. Defaults to "false".

/tellraw @a {"text":"Hello","strikethrough":true}

"obfuscated"

Boolean; causes text to cycle through random letters (example: ). Defaults to "false".

/tellraw @a {"text":"Hello","obfuscated":true}

Event listeners

"insertion"

When the player holds SHIFT and left-clicks text, the insertion event listener will fire. This will append text to the player's current chat input, provided their chat is open. This is restricted to /tellraw only.

/tellraw @a {"text":"Shift-click","insertion":"/say Hello"}

"clickEvent"

When the player left-clicks /tellraw or book text, or right-clicks on a sign, the clickEvent listener will fire.

For signs, all clickEvents must be at the root of inheritance. Clicking on a sign activates the listener for all of the Text1/Text2/Text3/Text4 tags, thus the maximum number of clickEvents on a sign is 4.

The event is stored within a clickEvent object, with an action string holding the type of event and a value holding the various relevant values that corresponds with the action.

List of clickEvents

The following is a list of all possible clickEvents that can be used.

/tellraw @a {"text":"Click","clickEvent":{"action":"open_url","value":"http://google.com"}}

/tellraw @a {"text":"Click","clickEvent":{"action":"run_command","value":"/say Must be OP'd to run this command"}}

/setblock ~ ~1 ~ minecraft:standing_sign 0 replace {Text1:"{\"text\":\"\",\"clickEvent\":{\"action\":\"run_command\",\"value\":\"say Does not need to be OP'd to run this command. Sender bias: @e[c=1] .\"}}",Text2:"[\"\"]",Text3:"[\"\"]",Text4:"[\"\"]"}

/setblock ~ ~1 ~ minecraft:standing_sign 0 replace {CommandStats:{SuccessCountName:"@p",SuccessCountObjective:"OBJ"},Text1:"{\"text\":\"\",\"clickEvent\":{\"action\":\"run_command\",\"value\":\"testfor @e[r=3]\"}}",Text2:"[{\"text\":\"\",\"clickEvent\":{\"action\":\"run_command\",\"value\":\"execute @p[score_OBJ_min=3] ~ ~ ~ say 3 entities around the sign.\"}}]",Text3:"[\"\"]",Text4:"[\"\"]"}

/tellraw @a {"text":"Click","clickEvent":{"action":"suggest_command","value":"Text replaced"}}

/give @p minecraft:written_book 1 0 {title:"",author:"",pages:["{\"text\":\"Go to Page 2\",\"clickEvent\":{\"action\":\"change_page\",\"value\":\"2\"}}","[\"Page 2\"]","[\"Page 3\"]"]}

"hoverEvent"

When the player hovers over /tellraw or book text with their mouse pointer, the hoverEvent listener will fire.

The event is stored within a hoverEvent object, with an action string holding the type of event and a value holding the various relevant values that corresponds with the action.

List of hoverEvents

The following is a list of all possible hoverEvents that can be used.

1. show_text
2. show_achievement
3. show_item
4. show_entity

show_text

Shows a tooltip populated by a text component, though could also just be a simple string.

Unavailable features:

1. All event listeners.
2. "score" text, though an explicit "value" will work.
3. "selector" text.

See MC-56373 for issues concerning "score" and "selector".

/tellraw @a {"text":"Hover","hoverEvent":{"action":"show_text","value":"Basic string"}}

/tellraw @a {"text":"Hover","hoverEvent":{"action":"show_text","value":["",{"text":"Text\n","color":"green","underlined":true},"component"]}}

show_achievement

Displays a pre-formatted achievement tooltip. May also show pre-formatted statistics tooltips, though will only show the statistic name. The wiki has a list of valid achievement IDs here, as well as statistic IDs here.

Achievements will be prefixed by "achievement." while statistics are prefixed by "stat.".

/tellraw @a {"text":"Hover","hoverEvent":{"action":"show_achievement","value":"achievement.openInventory"}}

/tellraw @a {"text":"Hover","hoverEvent":{"action":"show_achievement","value":"stat.walkOneCm"}}

The following shows the pre-formatted text template:



The first line will be the achievement or stat name, dependent on the string provided from "value".

The second line will either show "Achievement" or "Statistic" depending on the language setting, which is translated from the following keys in the language file:

stats.tooltip.type.achievement=Achievement
stats.tooltip.type.statistic=Statistic

The third line will display a description, which is only used for achievements.

If the value is not a valid achievement or statistic, it will instead display "Invalid statistic/achievement!".

show_item

Parses NBT input into an item and displays the result.

The value is a string and must have nested quotation marks escaped. Must be valid NBT input starting with an unnamed compound. Note that if Advanced Tooltips is shown (F3 + H), extra data will be shown as it normally would.

/tellraw @a {"text":"Hover","hoverEvent":{"action":"show_item","value":"{id:\"minecraft:stone\",tag:{display:{Lore:[\"Lore line 1\",\"Lore line 2\"]}}}"}}

If either the item data is invalid (wrong item ID, "Count" tag not 1+) or the NBT data is syntactically incorrect, "Invalid Item!" is shown instead.

show_entity

An advanced tooltip displaying an entity's name, type, and UUID. Advanced tooltips must be enabled to view (F3 + H). Note that this is not targeting any existing entities, but is instead just creating dummy text.

The value is a string and must have nested quotation marks escaped. The value is NBT input of a specific structure, rather than entity data, but none of the following tags are required and can simply be blank:

{

    name:"CustomName",

    type:"ArmorStand",

    id:"00000000-0000-0000-0000-000000000000"

}

None of the tags are required, but the game will render a line for both "name" and "id". "type" will only have a line dedicated to it if it's defined. The input does not need to be valid.

"name" is essentially the "CustomName" tag of the entity. "type" is the entity's savegame ID and will be appended by the corresponding numerical ID (90 (AKA Pig) if invalid). "id" is the UUID pair of the entity (determined by "UUIDLeast" and "UUIDMost" tags).

/tellraw @a {"text":"Hover","hoverEvent":{"action":"show_entity","value":"{name:\"Skylinerw\",type:\"Creeper\",id:\"00000000-0000-0000-0000-000000000000\"}"}}



/tellraw @a {"text":"Hover","hoverEvent":{"action":"show_entity","value":"{name:\"Skylinerw\",id:\"Not a valid UUID\"}"}}

If the NBT data is syntactically invalid, "Invalid Entity!" will be displayed instead.

Adding text

"extra"

The "extra" array will accept a list of text components and strings. This tag is used in order to create more text with their own options. Note that the text components here will inherit from a parent first, but each are their own separate child. See Inheritance for more info.

For example, the following results in the parent ("First") being red, while its children ("Second" and "Third") inherit that property and are also red. The first child ("Second") set itself to be bold, unlike its parent, while the second child ("Third") does not change any properties that it inherited.

/tellraw @a {"text":"First","color":"red","extra":[{"text":"Second","bold":true},"Third"]}

Array structure

A text component can instead be instantiated as an array rather than an object. This essentially allows one to skip using the "extra" tag entirely, and can also save on characters as it becomes quicker to nullify a parent.

/tellraw @a ["First","Second","Third"]

Note that the first record defined will be marked as the parent, and all other records will inherit from that parent. For example, the following causes the first record ("Parent") to be the parent set to red, while the second record ("Child") inherits everything from the first record and will also be red.

/tellraw @a [{"text":"Parent","color":"red"},"Child"]

A quick way to skip over the first record as the parent to avoid any unwanted inheritance is to simply input an empty string.

/tellraw @a ["",{"text":"Child1","color":"red"},{"text":"Child2","underlined":true}]

Additional usage info

Inheritance

/tellraw @a {"text":"Parent"}

The following shows a parent, with absolutely everything inside the "extra" tag being a child (including any "grandchildren" and so on).

/tellraw @a {"text":"Parent","extra":["Child1","Child2"]}

When instantiating as an array, the first record will be the parent while all other records are the children.

/tellraw @a ["Parent","Child1","Child2"]

Each child can be a parent to their own children, and only their children will inherit their properties (as well as any properties inherited by a grandparent and so on). The following shows a parent that is bold, a child that inherits boldness and has the italic property, and a grandchild that is both bold, italic, and has its own property of being red.

/tellraw @a {"text":"First","bold":true,"extra":[{"text":"Second","italic":true,"extra":[{"text":"Third","color":"red"}]}]}

/tellraw @a [{"text":"First","bold":true},{"text":"Second","italic":true,"extra":[{"text":"Third","color":"red"}]}]

/tellraw @a [{"text":"First","bold":true},[{"text":"Second","italic":true},{"text":"Third","color":"red"}]]

The following demonstrates that siblings do not inherit from one another. While the parent is bold and causes both its children to be bold, the first child will be italic while the second child is underlined (and not italic).

/tellraw @a {"text":"Parent","bold":true,"extra":[{"text":"Child1","italic":true},{"text":"Child2","underlined":true}]}

/tellraw @a [{"text":"Parent","bold":true},{"text":"Child1","italic":true},{"text":"Child2","underlined":true}]

Senders & origins

Initial parsing

When parsing the "selector" tag or the "name" tag in the "score" object, and if there is a command sender available, sender bias will apply, forcing them to always be the target.

This occurs when an entity runs a command (such as a player running the /tellraw or /title commands directly, or via the /execute command) or when the player opens a book for the first time.

For example, the following will cause all entities to say their own name no matter what:

/execute @e ~ ~ ~ /tellraw @a {"selector":"@e[c=1]"}

This functionality is not available for signs as they do not have a sender to work from, and instead their selectors will parse without a sender bias from the blockspace that they are placed at.

run_command clickEvents

When a player activates a run_command event, they will be marked as the command sender as they are naturally the ones running the command. However, there is a key difference with signs: while /tellraw and books will use the player's current coordinates as the origin, clickEvents in signs will instead use the sign's coordinates as the origin, while still setting the clicking player as the command sender for sender bias to apply.

For example, the following will cause the clicking player to set a block above the sign, rather than above themselves, and to always say their own name:

/setblock ~ ~1 ~ minecraft:standing_sign 0 replace {Text1:"[{\"text\":\"\",\"clickEvent\":{\"action\":\"run_command\",\"value\":\"setblock ~ ~1 ~ minecraft:stone\"}}]",Text2:"[\"\"]",Text3:"[\"\"]",Text4:"[{\"text\":\"\",\"clickEvent\":{\"action\":\"run_command\",\"value\":\"say @e[c=1]\"}}]"}

This can be used very effectively in order to know exactly which sign the player had clicked while still being able to target the clicking player.

/trigger

/trigger [trigger-objective] [add|set] [value]

Players that run this command will only be capable of targeting their own objective, noted by the lack of a target selector in the syntax.

In order for the command to modify a score, the objective itself must use the "trigger" objective-type. This objective-type has a special feature in that it will be 'locked' in order to prevent being modified. This occurs when the value is modified by the /trigger command, though do note that if a player is not tracked in the objective they will still be considered 'locked'. Example:

/scoreboard objectives add OBJECTIVE trigger
/scoreboard players add @a OBJECTIVE 0

The player's "OBJECTIVE" score will be enabled by default in this case. Changing their score with /scoreboard does not unlock the objective for the player, but because the player had never run /trigger yet, it will be enabled.

The following will cause the player to change their score to 1, and thus locking the objective for that player. The player will not be able to run /trigger to modify that score until they are unlocked.

/trigger OBJECTIVE set 1

The /scoreboard command can be used to unlock the objective.

/scoreboard players enable @a OBJECTIVE

The /execute command can be used to forcibly change a player's score by causing them to run /trigger. This can be useful to automatically lock a player's objective without waiting for them to run the command themselves. For example, the following will not change their score but will lock it:

/execute @a ~ ~ ~ /trigger OBJECTIVE add 0

Example usage with /tellraw:

/tellraw @a {"text":"Click","clickEvent":{"action":"run_command","value":"/trigger OBJECTIVE set 1"}}

The clicking player will set their "OBJECTIVE" score to 1 if it is enabled for that player, and if so, will then become disabled.

Conclusion

Q&A

External links

Conclusion

Index

Generic info

1. Intro
2. Errors
3. JSON Structure

Files

4. Location

5. Referencing
6. Replacing default tables

7. Editing

Loot Construct

8. General info
9. Luck
10. Looted entity ("this")
11. Player context ("killer_player")
12. Damage source ("killer")

Customizing tables

13. Pools
14. Entries

15. Rolls
16. Bonus rolls
17. Items

18. Conditions

19. Duplicate functions & conditions

Usage

20. generic.luck, Luck, Unluck, Luck of the Sea
21. NBT data

Conclusion

22. Custom table example
23. Q&A
24. External links
25. Conclusion

Generic info

Intro

Errors

[spoiler]Paste loot table and error here[/spoiler]

Common errors

1. Couldn't find resource table minecraft:tablename

2. Expected value at line # column #

3. Missing [key], expected to find a [type]

4. Expected loot table to be a JsonObject, was "??"

JSON Structure

{
    "pools": [
        {
            "rolls": 1,
            "rolls": {
                "min": 1,
                "max": 1
            },
            "entries": [
                {
                    "type": "[item|loot_table|empty]",
                    "name": "[ID|LootTable]",
                    "weight": 1,
                    "quality": 1.0,
                    "functions": [
                        {
                            "function": "[FunctionID]",
                            "treasure": true,
                            "tag": "{display:{Name:\"Test\"}}",
                            "data": 1,
                            "data": {
                                "min": 1,
                                "max": 1
                            },
                            "damage": 1,
                            "damage": {
                                "min": 1,
                                "max": 1
                            },
                            "count": 1,
                            "count": {
                                "min": 1,
                                "max": 1
                            },
                            "levels": 1,
                            "levels": {
                                "min": 1,
                                "max": 1
                            },
                            "limit": 1,
                            "conditions": [
                                (see "conditions" below)
                            ]
                        }
                    ],
                    "conditions": [
                        (see "conditions" below)
                    ]
                }
            ],
            "conditions": [
                {
                    "condition": "[ConditionID]",
                    "chance": 1.0,
                    "looting_multiplier": 1.0,
                    "inverse": true,
                    "entity": "this",
                    "properties": {
                        "minecraft:on_fire": true
                    },
                    "scores": {
                        "[ObjectiveName]": 1,
                        "[ObjectiveName]": {
                            "min": 1,
                            "max": 1
                        }
                    }
                }
            ]
        }
    ]
}

Files

Location

Namespaces

The folder that you create within the loot_tables folder will be referred to as the "namespace". This is what separates collections of loot tables, such as for different mods or maps. File/folder names must all be lowercase to circumvent issues with differing operating system file structures.

From the image example above, "skylinerwloot", "mocreatures", "anothermod", and "minecraft" are the namespaces.

The "minecraft" namespace in particular should only be used to overwrite default loot tables, such as replacing natural zombie drops. Place any new loot tables in a new namespace and not within "minecraft".

Referencing

[namespace]:[filepath/to/table]

anothermod:bears/grizzly

entities/zombie

Replacing default tables

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:feather",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:set_count",
                            "count": {
                                "min": 0,
                                "max": 2
                            }
                        }
                    ]
                }
            ]
        }
    ]
}

List of default tables

The wiki has a description for each of the default loot tables here.

Editing

1. Click Save or Save As.
2. Set "Save as type" to "All files (*.*)".
3. Name your file and append the name with ".json".
4. Set "Encoding" to "UTF-8".
5. Save.

Image example:

2. Notepad++ is a great alternative to using plain Notepad. Instructions for saving a .json in UTF-8:

1. Change the encoding to either "UTF-8" or "UTF-8 without BOM" under the "Encoding" menu. See image below.
2. Click Save or Save As.
3. Set "Save as type" to "All files (*.*)".
4. Name your file and append the name with ".json".
5. Save.

Image example:

3. Atom has multiple platform support.

Loot construct

General info

Luck

Looted entity ("this")

Player context ("killer_player")

Damage source ("killer")

Customizing tables

Pools

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1
                }
            ]
        },
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1
                },
                {
                    "type": "item",
                    "name": "minecraft:stick",
                    "weight": 1
                }
            ]
        }
    ]
}

Entries

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:feather",
                    "weight": 1
                },
                {
                    "type": "loot_table",
                    "name": "minecraft:entities/chicken",
                    "weight": 1
                },
                {
                    "type": "empty",
                    "weight": 1
                }
            ]
        }
    ]
}

item

States that the entry will be an actual item. The "name" string key is required and defines the item ID to be used. This particular type supports the use of "functions". See the Items section for extended usage of this type.

The following will provide either a stone or a feather.

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1
                },
                {
                    "type": "item",
                    "name": "minecraft:feather",
                    "weight": 1
                }
            ]
        }
    ]
}

loot_table

States that the entry will be another loot table. This simplifies loot tables that uses the same data as another. The "name" string key is required and defines which loot table is to be used. Does not support "functions".

Note that the other loot table's provided item is not affected by this loot table. If the other loot table has 3 rolls while this one has 1, the other loot table will cycle through all 3 of its own rolls.

A loot table may not point to itself in any manner. If the root loot table points to a second loot table that selects the root in a loop, the loot table will not function and no item will be provided.

The following will provide either an item from its own loot table, or provide item(s) from another loot table.

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1
                },
                {
                    "type": "item",
                    "name": "minecraft:feather",
                    "weight": 1
                },
                {
                    "type": "loot_table",
                    "name": "minecraft:entities/zombie",
                    "weight": 1
                }
            ]
        }
    ]
}

empty

States that the entry will be nothing. No item will be provided. Does not support "functions" and the "name" string key cannot be used. While "conditions" may be used, they are essentially useless.

The following will provide either nothing or a stone.

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "empty",
                    "weight": 1
                },
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1
                }
            ]
        }
    ]
}

Rolls

{
    "pools": [
        {
            "rolls": 3,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1
                },
                {
                    "type": "item",
                    "name": "minecraft:stick",
                    "weight": 1
                }
            ]
        }
    ]
}

The following will provide between 1 and 5 results from the list of items.

{
    "pools": [
        {
            "rolls": {
                "min": 1,
                "max": 5
            },
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1
                },
                {
                    "type": "item",
                    "name": "minecraft:stick",
                    "weight": 1
                }
            ]
        }
    ]
}

Bonus rolls

rolls + (bonus_rolls * generic.luck)

As such, if the bonus roll is negative while luck is positive, the number of total rolls provided is decreased. For example, with 1 roll, -1 bonus rolls, and a luck value of 1, the result is 0 rolls from that pool:

1 + (-1 * 1) = 0

The following will always provide 2 stone (due to 2 initial rolls), and will also provide 1 extra stone for each point of "luck" the player has. If the player has 0 luck, they will be given 2 stone. If they have 1 luck, they will be given 3 stone.

{
    "pools": [
        {
            "rolls": 2,
            "bonus_rolls":1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1
                }
            ]
        }
    ]
}

The following will provide between 2-6 extra stone.

{
    "pools": [
        {
            "rolls": 2,
            "bonus_rolls": {
                "min": 2,
                "max": 6
            },
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1
                }
            ]
        }
    ]
}

Items

Weight

A weight determines the chances of an item being picked in comparison to the weights of other items. If all items have the same weight, they all have the same chance of being picked. A weight is defined by the "weight" integer key and is optional. If not specified, the value defaults to 1. The following will provide 1 stone at half the rate as 1 stick.

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1
                },
                {
                    "type": "item",
                    "name": "minecraft:stick",
                    "weight": 2
                }
            ]
        }
    ]
}

To get an idea of how weights are used, imagine the instance of each item being multiplied by its weight. Using the above table, the following is a visual representation in which there are 2 sticks (weight of 2) and 1 stone (weight of 1). Since there are 2 sticks, they have a higher chance (exactly double) of being chosen compared to stone.

minecraft:stone, minecraft:stick, minecraft:stick

Quality

See also: bonus_rolls, Luck usage

Optionally changes the "weight" of the entry based on the killing/opening/fishing player's "generic.luck" attribute value. The attribute can be modified by either worn gear with the "AttributeModifiers" list or by giving the player the "Luck" potion effect.

The formula is:

weight + (quality * generic.luck)

The following will provide either stone or diamond at equal rates while the player does not have any Luck, but if the player has a Luck value of 2, the diamond will have its "weight" changed to 7.

{
    "pools": [
        {
            "rolls": 20,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1
                },
                {
                    "type": "item",
                    "name": "minecraft:diamond",
                    "weight": 1,
                    "quality": 3
                }
            ]
        }
    ]
}

Functions

Functions are optional operations to perform on the item, such as providing it a count between two values, giving it NBT data or a Damage value, as well as enchanting it using a random enchantment. The "functions" list will hold multiple compounds, while the "function" string key states which function is to be used. Individual functions may ask for more data, which is covered in the next section.

The IDs for functions will have the resource namespace default to "minecraft" (e.g. "minecraft:set_attributes") when not specified. If using mods, the namespace will be whatever the mod has implemented. Note that you cannot create your own functions without modding.

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:diamond_sword",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "set_damage",
                            "damage": 0.6
                        },
                        {
                            "function": "minecraft:enchant_with_levels",
                            "levels": {
                                "min": 20,
                                "max": 30
                            }
                        }
                    ]
                }
            ]
        }
    ]
}

List of functions

The following is a list of all possible functions that can be used, along with any extra applicable data. Open the spoiler before clicking a link to be taken to the description.

1. set_count
2. set_data
3. set_damage
4. set_nbt
5. set_attributes
6. enchant_randomly
7. enchant_with_levels
8. looting_enchant
9. furnace_smelt

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:set_count",
                            "count": 4
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:set_count",
                            "count": {
                                "min": 3,
                                "max": 5
                            }
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:skull",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:set_data",
                            "data": 3
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:dye",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:set_data",
                            "data": {
                                "min": 1,
                                "max": 4
                            }
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:diamond_sword",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:set_damage",
                            "damage": 0.5
                        }
                    ]
                },
                {
                    "type": "item",
                    "name": "minecraft:diamond_sword",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:set_damage",
                            "damage": {
                                "min": 0.75,
                                "max": 1
                            }
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:diamond_sword",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:set_nbt",
                            "tag": "{display:{Name:\"Test\"}}"
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:diamond_sword",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:set_attributes",
                            "modifiers": [
                                {
                                    "attribute": "generic.maxHealth",
                                    "name": "More Health",
                                    "amount": {
                                        "min": 3.5,
                                        "max": 6
                                    },
                                    "operation": "addition",
                                    "slot": [
                                        "mainhand",
                                        "offhand"
                                    ]
                                }
                            ]
                        }
                    ]
                }
            ]
        }
    ]
}

{

    "pools": [

        {

            "rolls": 1,

            "entries": [

                {

                    "type": "item",

                    "name": "minecraft:diamond_sword",

                    "weight": 1,

                    "functions": [

                        {

                            "function": "minecraft:set_attributes",

                            "modifiers": [

                                {

                                    "attribute": "generic.attackDamage",

                                    "name": "More Damage",

                                    "amount": 1,

                                    "operation": "addition",

                                    "slot": "chest",

                                    "id": "00000000-0000-0001-0000-000000000001"

                                }

                            ]

                        }

                    ]

                }

            ]

        }

    ]

}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:diamond_sword",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:enchant_randomly",
                            "enchantments": [
                                "minecraft:looting",
                                "minecraft:depth_strider",
                                "minecraft:sharpness"
                            ]
                        },
                        {
                            "function": "minecraft:enchant_randomly"
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:diamond_sword",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:enchant_with_levels",
                            "levels": 30,
                            "treasure": true
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:diamond_sword",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:enchant_with_levels",
                            "levels": {
                                "min": 25,
                                "max": 30
                            }
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:looting_enchant",
                            "count": 30,
                            "limit": 80
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:looting_enchant",
                            "count": {
                                "min": 10,
                                "max": 20
                            }
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:log",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:furnace_smelt"
                        }
                    ]
                }
            ]
        }
    ]
}

Conditions

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1
                },
                {
                    "type": "item",
                    "name": "minecraft:stick",
                    "weight": 1
                }
            ],
            "conditions": [
                {
                    "condition": "killed_by_player"
                }
            ]
        }
    ]
}

The following only provides the individual item if the condition is met. The stone will always drop, but the stick will only drop when killed by a player. If the conditions are not met when selecting an item, the entry will not be selected. The pool will not re-roll and ignores the entry instead.

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1
                },
                {
                    "type": "item",
                    "name": "minecraft:stick",
                    "weight": 1,
                    "conditions": [
                        {
                            "condition": "minecraft:killed_by_player"
                        }
                    ]
                }
            ]
        }
    ]
}

The following will only run the individual function if a condition was met. The following will run the "furnace_smelt" function only if the mob was killed by a player. If a player kills the mob, smooth stone will drop. Otherwise, cobblestone will drop.

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:cobblestone",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:furnace_smelt",
                            "conditions": [
                                {
                                    "condition": "minecraft:killed_by_player"
                                }
                            ]
                        }
                    ]
                }
            ]
        }
    ]
}

List of conditions

The following is a list of all conditions that can be used. Open the spoiler before clicking a link to be taken to the description.

1. random_chance
2. random_chance_with_looting
3. killed_by_player
4. entity_properties
5. entity_scores

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:cobblestone",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:furnace_smelt",
                            "conditions": [
                                {
                                    "condition": "minecraft:random_chance",
                                    "chance": 0.3
                                }
                            ]
                        }
                    ]
                }
            ]
        }
    ]
}

chance + (looting_level * looting_multiplier)

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:cobblestone",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:furnace_smelt",
                            "conditions": [
                                {
                                    "condition": "minecraft:random_chance_with_looting",
                                    "chance": 0.1,
                                    "looting_multiplier": 0.15
                                }
                            ]
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:cobblestone",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:furnace_smelt",
                            "conditions": [
                                {
                                    "condition": "minecraft:killed_by_player",
                                    "inverse": true
                                }
                            ]
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:cobblestone",
                    "weight": 1,
                    "conditions": [
                        {
                            "condition": "minecraft:entity_properties",
                            "entity": "this",
                            "properties": {
                                "minecraft:on_fire": true
                            }
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:cobblestone",
                    "weight": 1,
                    "conditions": [
                        {
                            "condition": "minecraft:entity_properties",
                            "entity": "killer_player",
                            "properties": {
                                "minecraft:on_fire": false
                            }
                        }
                    ]
                }
            ]
        }
    ]
}

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:cobblestone",
                    "weight": 1,
                    "conditions": [
                        {
                            "condition": "minecraft:entity_scores",
                            "entity": "killer_player",
                            "scores": {
                                "ObjA": 1,
                                "ObjB": {
                                    "min": 1,
                                    "max": 25
                                }
                            }
                        }
                    ]
                }
            ]
        }
    ]
}

Duplicate functions & conditions

Functions

set_count

Only the last "set_count" function specified will be used.

set_data

Only the last "set_data" function specified will be used.

set_damage

Only the last "set_damage" function specified will be used.

set_nbt

NBT data will merge. If duplicate tags are declared, the last "set_nbt" function specified will take precedence. For example, the following would provide an item that contains the lore from the first function, but the second function overwrites the display name from the first.

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:cobblestone",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:set_nbt",
                            "tag": "{display:{Name:\"Function 1\",Lore:[\"text\"]}}"
                        },
                        {
                            "function": "minecraft:set_nbt",
                            "tag": "{display:{Name:\"Function 2\"}}"
                        }
                    ]
                }
            ]
        }
    ]
}

set_attributes

Attributes will be appended. Note that if "id" is duplicated, the game will not account for it. Do not use multiple of the same UUID.

enchant_randomly

Enchantments will be appended, rather than merged. Note that if the same enchantment is picked twice, they will not merge together and will instead be listed one after the other (and does not have to have the same level).

enchant_with_levels

Enchantments will be appended, rather than merged. Note that if the same enchantment is picked twice, they will not merge together and will instead be listed one after the other (and does not have to have the same level).

looting_enchant

Counts will be merged. For example, the following provides 42 stone with Looting I; 1 for initial, an extra 30 for the first function, and an extra 11 for the second function.

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:looting_enchant",
                            "count": 30
                        },
                        {
                            "function": "minecraft:looting_enchant",
                            "count": 11
                        }
                    ]
                }
            ]
        }
    ]
}

furnace_smelt

Each function will run one at a time, processing the item before moving on to the next. For example, in the following, the first function will turn the cactus into green dye, and the second function will fail because green dye has no smelting recipe.

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:cactus",
                    "weight": 1,
                    "functions": [
                        {
                            "function": "minecraft:furnace_smelt"
                        },
                        {
                            "function": "minecraft:furnace_smelt"
                        }
                    ]
                }
            ]
        }
    ]
}

Conditions

random_chance

Each condition runs one at a time (so long as no conditions fail), which can greatly change the rate of selection. For example, the following has a 50% chance for the first function, and if the first function succeeded, a 25% chance for the second function.

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:stone_sword",
                    "weight": 1,
                    "conditions": [
                        {
                            "condition": "minecraft:random_chance",
                            "chance": 0.5
                        },
                        {
                            "condition": "minecraft:random_chance",
                            "chance": 0.25
                        }
                    ]
                }
            ]
        }
    ]
}

random_chance_with_looting

Each condition runs one at a time (so long as no conditions fail), which can greatly change the rate of selection. See Duplicate random_chance, which essentially functions the same way (albeit without a looting multiplier).

killed_by_player

Each condition runs one at a time (so long as no conditions fail). However, since the only option is whether or not the mob was killed by a player, it would be pointless to have multiple of these conditions at the same depth.

entity_properties

Each condition runs one at a time (so long as no conditions fail). It would be pointless to have multiple of these conditions if "entity" remained the same. However, it will function well for different targets. For example, the following would provide stone so long as both the mob and the killer were on fire.

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:cobblestone",
                    "weight": 1,
                    "conditions": [
                        {
                            "condition": "minecraft:entity_properties",
                            "entity": "this",
                            "properties": {
                                "on_fire": true
                            }
                        },
                        {
                            "condition": "minecraft:entity_properties",
                            "entity": "killer",
                            "properties": {
                                "on_fire": true
                            }
                        }
                    ]
                }
            ]
        }
    ]
}

entity_scores

Each condition runs one at a time (so long as no conditions fail). It would be pointless to have multiple of these conditions if "entity" remained the same. However, it will function well for different targets. For example, the following would provide stone so long as the killed mob had an "ObjA" score of 1, and the killer had an "ObjA" score between 1 and 2.

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:cobblestone",
                    "weight": 1,
                    "conditions": [
                        {
                            "condition": "minecraft:entity_scores",
                            "entity": "this",
                            "scores": {
                                "ObjA": 1
                            }
                        },
                        {
                            "condition": "minecraft:entity_scores",
                            "entity": "killer",
                            "scores": {
                                "ObjA": {
                                    "min": 1,
                                    "max": 2
                                }
                            }
                        }
                    ]
                }
            ]
        }
    ]
}

Usage

generic.luck, Luck, Unluck, Luck of the Sea

/give @p minecraft:iron_ingot 1 0 {AttributeModifiers:[{AttributeName:"generic.luck",Name:"More Luck",Amount:2.0,Operation:0,Slot:"offhand",UUIDLeast:1l,UUIDMost:1l}]}

The "Luck" and "Unluck" potion effects will apply modifiers to the player's "generic.luck" attribute, adding 1.0 per effect level of "Luck" or removing 1.0 per effect level of "Unluck". For example, the following gives the player "Luck" 10 and "Unluck" 4, which has a final resulting "generic.luck" value of 6:

/effect @p minecraft:luck 30 9
/effect @p minecraft:unluck 30 3

The "Luck of the Sea" enchantment does not directly add an attribute modifier like the "Luck" or "Unluck" effects. Instead, the level of the enchantment is added onto the player's final "generic.luck" value (but only when obtaining fishing loot). As such, the enchantment supersedes other modifiers placed on the player. If the player had a modifier that reduced their attribute value by 100% (which occurs after any addition modifiers), their enchantment would still work because it is adding the enchantment level onto the final base of 0.0.

For example, the following provides the player with a "multiply total" attribute modifier, reducing their "generic.luck" by 100%, as well as a fishing rod with a high "Luck of the Sea" enchantment. The result is the player being guaranteed to fish treasure items because the enchantment value is added after obtaining the final attribute value (0.0 attribute + 85 enchantment = 85 "luck", the lowest value needed to guarantee treasure from fishing):

/give @p minecraft:iron_helmet 1 0 {AttributeModifiers:[{AttributeName:"generic.luck",Name:"100% reduction",Amount:-1.0,Operation:2,Slot:"head",UUIDLeast:1l,UUIDMost:1l}]}

/give @p minecraft:fishing_rod 1 0 {ench:[{id:61s,lvl:85s}]}

After all of these values are totalled up, the resulting value is what loot tables will use when modifying the "bonus_rolls" and "quality" tags.

For example, the following gives the player an iron helmet that, when worn, increases the player's "generic.luck" value by 100% (doubling their value), a "Luck" effect of 40 (which provides a modifier of +40.0), and a fishing rod with a "Luck of the Sea 5" enchantment. The result is a final attribute value of 80.0 (40 * 2), with 5 added on from the enchantment, finally resulting in 85 (guaranteeing treasure while fishing):

/give @p minecraft:iron_helmet 1 0 {AttributeModifiers:[{AttributeName:"generic.luck",Name:"100% More",Amount:1.0,Operation:2,Slot:"head",UUIDLeast:1l,UUIDMost:1l}]}

/effect @p minecraft:luck 30 39

/give @p minecraft:fishing_rod 1 0 {ench:[{id:61s,lvl:5s}]}

NBT data

/setblock ~ ~1 ~ minecraft:chest 0 false {LootTable:"minecraft:chests/simple_dungeon"}

"LootTableSeed" (long)

Instead of being random every single time, inventory population can be deterministic based on seed. A default survival world will use this to always generate the same loot whenever a new world with the same seed is created. Value must not be 0, otherwise a new seed will be chosen randomly. This tag's usage is restricted to the following: chests, hoppers, dispensers, droppers, minecart chests, minecart hoppers.

/setblock ~ ~1 ~ minecraft:chest 0 false {LootTable:"minecraft:chests/simple_dungeon",LootTableSeed:123L}

"DeathLootTable" (string)

Mobs use this tag to determine what loot table is used when killed. Note that the "HandItems/ArmorItems" data for mobs is unrelated to loot tables and can drop separate items.

/summon Creeper ~ ~1 ~ {DeathLootTable:"minecraft:chests/simple_dungeon"}

"DeathLootTableSeed" (long)

Same as "LootTableSeed", except for mobs.

/summon Creeper ~ ~1 ~ {DeathLootTable:"minecraft:chests/simple_dungeon",DeathLootTableSeed:123L}

Empty tables

An empty loot table may be declared by using "minecraft:empty". This will prevent any default loot from generating, provided that this table has not been overwritten with a custom table.

/summon Creeper ~ ~1 ~ {LootTable:"minecraft:empty"}

Conclusion

Custom table example

{
    "pools": [
        {
            "rolls": 1,
            "entries": [
                {
                    "type": "item",
                    "name": "minecraft:tnt",
                    "weight": 1,
                    "conditions": [
                        {
                            "condition": "minecraft:random_chance",
                            "chance": 0.01
                        },
                        {
                            "condition": "minecraft:killed_by_player"
                        },
                        {
                            "condition": "minecraft:entity_properties",
                            "entity": "this",
                            "properties": {
                                "minecraft:on_fire": true
                            }
                        }
                    ]
                }
            ]
        }
    ]
}

And then using that in-game is the same as before, replacing the name with the name given to the JSON file. The following summons a creeper that, when killed, has a 1% chance to drop TNT when killed by a player and on fire.

/summon Creeper ~ ~1 ~ {DeathLootTable:"customloot:entities/custom_table_a"}

Q&A

External links

Conclusion

Index

Generic info

1. Intro
2. JSON structure
3. Shared: item object

Customizing recipes

4. Type
5. Groups
6. Shaped crafting

7. Shapeless crafting

8. Results

Commands

9. Command: /recipe

Conclusion

10. Q&A
11. External links
12. Conclusion

Generic info

Intro

JSON Structure

{
    "type": "crafting_shaped",
    "group": "identifier",
    "pattern: [
        "###",
        "###",
        "###"
    ],
    "key": {
        "#": {
            "item": "minecraft:stone",
            "data": 0
            "count": 1
        }
    },
    "ingredients": [
        {
            "item": "minecraft:stone",
            "data": 0,
            "count": 1
        }
    ],
    "result": {
        "item": "minecraft:stone",
        "data": 0,
        "count": 1
    }
}

Shared: item object

"item_object": {
    "item": "minecraft:redstone"
}

2. "data"

The optional "data" number specifies a metadata of the item. The following either looks for or creates a polished granite block.

"item_object": {
    "item": "minecraft:stone",
    "data": 2
}

When used in a key or ingredient, not specifying this tag or giving it a value of 32767 will indicate that the metadata value can be anything. When used in a result, it will set the item's metadata to the value specified, defaulting to 0 when not specified.

3. "count"

The optional "count" number specifies the number of items in the stack, defaulting to 1 when not specified. This cannot be used in a key or ingredient, only in a result. The following creates an item with a stacksize of 16.

"item_object": {
    "item": "minecraft:stick",
    "count": 16
}

Customizing recipes

Type

{
    "type": "crafting_shaped",
    "pattern": [
        "###",
        "###",
        "###"
    ],
    "key": {
        "#": {
            "item": "minecraft:redstone"
        }
    },
    "result": {
        "item": "minecraft:stone"
    }
}

While the following recipe makes use of shapeless crafting.

{
    "type": "crafting_shapeless",
    "ingredients": [
        {
            "item": "minecraft:redstone"
        }
    ],
    "result": {
        "item": "minecraft:stone"
    }
}

Groups

{
    "type": "crafting_shapeless",
    "group": "stuff",
    "ingredients": [
        {
            "item": "minecraft:sand"
        }
    ],
    "result": {
        "item": "minecraft:diamond"
    }
}

{
    "type": "crafting_shapeless",
    "group": "stuff",
    "ingredients": [
        {
            "item": "minecraft:dirt"
        }
    ],
    "result": {
        "item": "minecraft:diamond"
    }
}

Shaped crafting

{
    "type": "crafting_shaped",
    "pattern": [
        "###",
        "^^^",
        "###"
    ],
    "key": {
        "#": {
            "item": "minecraft:redstone"
        },
        "^": {
            "item": "minecraft:iron_block"
        }
    },
    "result": {
        "item": "minecraft:gold_block"
    }
}

Image example of how it is used in the crafting window:

Patterns

A pattern must be specified via the "pattern" list. The list must contain between 1 and 3 strings, with each string representing a row in the crafting grid. Within each string there must be between 1 and 3 placeholder characters of your choosing, with each character representing a column. A space character indicates an empty slot in the crafting window, where no items are allowed to appear. The shape will automatically adapt to larger crafting grids, such that a 2x2 recipe will work in any corner of a 3x3 crafting grid.

For example, the following pattern uses only 1 row and all 3 columns, with an empty slot between the two items:

"pattern": [
    "# #"
]

Which could look like any of the following in the crafting window:



All strings must contain the same number of characters. The following pattern is invalid due to the uneven rows.

"pattern": [
    "###",
    "##"
]

The fix would be to specify an empty slot where the rows are uneven.

"pattern": [
    "###",
    "## "
]

The fixed pattern could look like any of the following in the crafting window:

"pattern": [
    "!@#",
    "$%^",
    "&*("
]

You can also use a single row and column to create a recipe where the item may be placed anywhere in the crafting grid, although you should use shapeless crafting instead as it is for unordered recipes.

"pattern": [
    "#"
]

Which could look like the following in the crafting window:

Keys

A set of keys must be specified via the "key" object. This object contains multiple item objects, whose key names must be equal to the unique characters specified in the pattern. The key name can only be 1 character long and cannot be the reserved space character.

The following pattern set uses "H" and "?" as the placeholders, while the key defines what items those placeholders will be. The "H" represents a lever, while the "?" represents a bone.

"pattern": [
    "H?H",
    "?H?",
    "H?H"
],
"key": {
    "H": {
        "item": "minecraft:lever"
    },
    "?": {
        "item": "minecraft:bone"
    }
}

Which would look like the following in the crafting window:

"pattern": [
    "###",
    "555",
    "TTT"
],
"key": {
    "#": {
        "item": "minecraft:stone"
    },
    "5": {
        "item": "minecraft:diamond_sword"
    },
    "T": {
        "item": "minecraft:wool",
        "data": 32767
    }
}

Which could look like the following in the crafting window:



To work around that, you would specify the metadata value. The following pattern set ensures that the incoming diamond swords are brand new.

"pattern": [
    "##"
],
"key": {
    "#": {
        "item": "minecraft:diamond_sword",
        "data": 0
    }
}

Shapeless crafting

{
    "type": "crafting_shapeless",
    "ingredients": [
        {
            "item": "minecraft:diamond"
        },
        {
            "item": "minecraft:nether_star"
        }
    ],
    "result": {
        "item": "minecraft:stick"
    }
}

Image example of how it is used in the crafting window:

Ingredients

A set of required items must be specified via the "ingredients" list. This list contains item objects; if the player does not provide all items in this list, the recipe will not work. There is no limit to the number of items, though be aware that in vanilla there can only be 9 total items to provide in a crafting table.

The following will only work if the player provides all 5 items, which also means they cannot use the standard inventory crafting grid (2x2) to craft the item as there is not enough room.

"ingredients": [
    {
        "item": "minecraft:redstone"
    },
    {
        "item": "minecraft:diamond"
    },
    {
        "item": "minecraft:iron_block"
    },
    {
        "item": "minecraft:gold_block"
    },
    {
        "item": "minecraft:diamond_block"
    }
]

Which could look like the following in the crafting window, plus many more combinations:



You can use the same item multiple times, in which the player must provide all instances of that item.

"ingredients": [
    {
        "item": "minecraft:golden_carrot"
    },
    {
        "item": "minecraft:golden_carrot"
    }
]

Which could look like the following in the crafting window:



You can also require just a single item, and that item can be placed anywhere in the crafting window.

"ingredients": [
    {
        "item": "minecraft:torch"
    }
]

Which could look like the following in the crafting window:

"ingredients": [
    {
        "item": "minecraft:stone"
    },
    {
        "item": "minecraft:diamond_sword"
    },
    {
        "item": "minecraft:wool",
        "data": 32767
    }
]

Which could look like the following in the crafting window:



To work around that, you would specify the metadata value. The following ensures that the incoming diamond swords are brand new.

"ingredients": [
    {
        "item": "minecraft:diamond_sword",
        "data": 0
    ]
}

Results

{
    "type": "crafting_shaped",
    "pattern": [
        "#%#",
        " # "
    ],
    "key": {
        "%": {
            "item": "minecraft:anvil",
            "data": 2
        },
        "#": {
            "item": "minecraft:iron_ingot"
        }
    },
    "result": {
        "item": "minecraft:anvil",
        "data": 0
    }
}

Unlike in "key" and "ingredients" item objects, the "count" key may be specified in "result" to provide the player with multiple items. The following shapeless recipe will create 4 sticks when the recipe is fulfilled.

{
    "type": "crafting_shapeless",
    "ingredients": [
        {
            "item": "minecraft:flint"
        },
        {
            "item": "minecraft:wheat_seeds"
        }
    ],
    "result": {
        "item": "minecraft:stick",
        "count": 4
    }
}

Commands

Command: /recipe

Conclusion

Q&A

External links

Conclusion

Quote from pyaroshi»

Is there a way to do this in 1.13 (snapshot)?

Yes, though quite a bit differently. CommandStats as a whole has been overhauled and no longer directly stores data on the entity/block. Instead, /execute stores the result of a command directly to a target's score. That way the only prerequisite is the objective itself, no /stats or other /scoreboard commands.

Prerequisites:

The objective to track the number of items in:

/scoreboard objectives add ITEMS dummy

Triggering:

The following command will set each player's own score based on the number of the specified items that they have in their inventory:

/execute as @a store result score @s ITEMS run clear @s minecraft:cobblestone 0

And to target players afterwards:

/say Players with 30+ cobblestone: @a[scores={ITEMS=30..}]

/execute as @p store result entity @e[type=minecraft:creeper,limit=1,sort=nearest] Health float 1.0 run clear @s minecraft:cobblestone 0

Quote from Juiseboy»

Is this a bug? It worked with other entities but not iron golems

It's not. What's happening is when the internal list of savegame entities is instantiated, some of them come with "spawn egg colors" to indicate that they have a spawn egg. Anything that does not have those egg colors will not get a corresponding egg, thus preventing the custom egg from working. On top of that, statistics rely on the same list of entities that are available for spawn eggs, hence why there's no "stat.killEntity" for iron golems, ender dragons, etc. (though those can be worked around using the "player_killed_entity" advancement trigger).