Custom Advancements JSON Examples: Root, Task, and Rewards

Complete working examples of Custom Advancements JSON files for Minecraft 1.18.2, from a simple root tab to a multi-condition advancement with rewards.

The three examples below are the actual files the mod copies into customadvancements/customadvancements/ the first time that folder is created. They form a small, self-contained advancement tree: a root tab, a simple task child, and a reward-bearing task that chains off the second. Together they demonstrate every common pattern you will encounter when writing your own advancements.

All three files belong to the customadvancements namespace. If you deleted them and want them back, remove the customadvancements/customadvancements/ folder and restart the game — the mod recreates it and copies the examples in again.

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1. Root Advancement — root.json

A root advancement defines an entirely new tab in the advancement screen. It has no parent field, and its display block must include a background — a root without one fails validation and is skipped. The minecraft:tick trigger fires every game tick, so the root completes silently the moment any player logs in.

root.json

{
  "display": {
    "icon": {
      "item": "minecraft:diamond_block"
    },
    "title": {
      "translate": "customadvancements.advancements.example_root.title"
    },
    "description": {
      "translate": "customadvancements.advancements.example_root.description"
    },
    "background": "customadvancements:textures/screenshot.png",
    "largeBackground": true,
    "shouldBgClip": true,
    "bgRatio": 1.7208029197,
    "show_toast": false,
    "announce_to_chat": false,
    "hidden": false
  },
  "criteria": {
    "requirement": {
      "trigger": "minecraft:tick"
    }
  }
}

Notable fields:

• background — Points at screenshot.png, one of the two example images the mod copies into customadvancements/data/textures/. A file in that folder is referenced as customadvancements:textures/<filename>. See Textures.
• largeBackground, shouldBgClip, bgRatio — The three mod-specific fields that make the image fill the whole panel at its correct proportions instead of tiling. The bgRatio value here is simply the example image’s width divided by its height. See Backgrounds.
• show_toast: false and announce_to_chat: false — Root advancements that complete on every login should never fire notifications; these two flags suppress both the toast overlay and the chat broadcast.
• hidden: false — The root is always visible in the tab, so there is no reason to hide it.
• minecraft:tick trigger — The simplest possible trigger. No conditions block is needed because the tick trigger always fires unconditionally.
• translate titles — The strings live in customadvancements/data/lang/en_us.json and three other locale files, also copied in by the mod. See Language Files.

---

2. Simple Task — example.json

A standard child advancement linked to the root above. It completes as soon as dirt appears anywhere in the player’s inventory, triggering a toast and a chat announcement.

example.json

{
  "display": {
    "icon": {
      "item": "minecraft:dirt"
    },
    "title": {
      "translate": "customadvancements.advancements.example_example.title"
    },
    "description": {
      "translate": "customadvancements.advancements.example_example.description"
    },
    "frame": "task",
    "show_toast": true,
    "announce_to_chat": true
  },
  "parent": "customadvancements:root",
  "criteria": {
    "requirement": {
      "trigger": "minecraft:inventory_changed",
      "conditions": {
        "items": [
          {
            "item": "minecraft:dirt"
          }
        ]
      }
    }
  }
}

Notable fields:

• parent: "customadvancements:root" — Links this advancement as a child of root.json. The resource location is the namespace (customadvancements) plus the file path without the .json extension (root).
• frame: "task" — Renders the standard square frame around the icon. Use "goal" for a rounded frame or "challenge" for the ornate frame on more difficult objectives.
• minecraft:inventory_changed trigger — Fires whenever the player’s inventory changes. The conditions.items array narrows it to fire only when at least one minecraft:dirt item is present. Note the singular "item" key — that is the Minecraft 1.18.2 item predicate format.
• No background — Child advancements never need one; the field would be ignored anyway.
• No requirements field — With only one criterion, omitting requirements means that single criterion must be satisfied, which is equivalent to [["requirement"]].

---

3. Task with Rewards — back_to_the_roots.json

This advancement chains off example.json and requires the player to kill an adult zombie while holding rotten flesh in their main hand. On completion it grants 50 experience points.

back_to_the_roots.json

{
  "parent": "customadvancements:example",
  "criteria": {
    "back_to_the_roots": {
      "conditions": {
        "entity": [
          {
            "condition": "minecraft:entity_properties",
            "entity": "this",
            "predicate": {
              "type": "minecraft:zombie",
              "flags": {
                "is_baby": false
              }
            }
          }
        ],
        "killing_blow": {
          "direct_entity": {
            "equipment": {
              "mainhand": {
                "items": [
                  "minecraft:rotten_flesh"
                ]
              }
            }
          }
        }
      },
      "trigger": "minecraft:player_killed_entity"
    }
  },
  "display": {
    "announce_to_chat": true,
    "description": {
      "translate": "customadvancements.advancements.back_to_the_roots.description"
    },
    "frame": "task",
    "hidden": false,
    "icon": {
      "item": "minecraft:rotten_flesh"
    },
    "show_toast": true,
    "title": {
      "translate": "customadvancements.advancements.back_to_the_roots.title"
    }
  },
  "requirements": [
    [
      "back_to_the_roots"
    ]
  ],
  "rewards": {
    "experience": 50
  }
}

Notable fields:

• minecraft:player_killed_entity trigger — Fires when the player lands the killing blow on any entity.
• conditions.entity — An array of condition objects the killed entity must match. The single entry uses minecraft:entity_properties to assert that the entity is a minecraft:zombie and is not a baby (is_baby: false).
• conditions.killing_blow — Inspects the damage source. The direct_entity.equipment.mainhand.items array requires the player to be holding minecraft:rotten_flesh in their main hand when the kill lands.
• requirements — Explicitly lists the single criterion. With only one criterion this is optional, but including it makes the intent obvious.
• rewards.experience: 50 — Awards 50 XP points directly to the player on completion. See Criteria for the other reward types.
• Field order — Note that parent and criteria come before display in this file. JSON object key order is irrelevant; the mod reads fields by name.

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Using Vanilla Advancements as Templates

Writing advancement JSON from scratch is tedious when you are not sure what a complex conditions block should look like. The /ca generate advancement all command exports every currently loaded advancement — vanilla and mod-added alike — as a ready-to-edit JSON file placed into customadvancements/<namespace>/.

/ca generate advancement all

This gives you accurate, working examples of every trigger type and condition structure Minecraft 1.18.2 uses, which you can copy and adapt for your own advancements. It also means those exported files now override the originals, so delete any you do not intend to change.

To export just one advancement instead of everything:

/ca generate advancement minecraft:story/mine_stone

See Commands for the full command reference.

Run /ca generate resource_locations first to dump every loaded advancement ID to customadvancements/resource_locations.txt. That makes it easy to find the exact ID of an advancement you want to inspect or override before running the generate command.

For the complete field reference used in these examples, see Structure, Display, and Criteria.