Items & Equipment

Items are passed exactly as returned by the UESP public item API — no transformation needed. The library feeds them into the engine, which applies armor ratings, traits, enchantments and set bonuses with its own rules.

Fetching an item from the UESP API

const res = await fetch(
  'https://esolog.uesp.net/exportJson.php?table=minedItem&id=70&level=50&quality=5',
);
const data = await res.json();
const item = data.minedItem[0]; // pick the row matching your level/quality

The API returns every level/quality variant of an item — filter the minedItem[] array for the level/quality you want.

Equipping items

Map each item to an EquipSlot:

const stats = calculateBuild({
  character: { /* ... */ },
  items: {
    Chest: chestItem,
    Head: headItem,
    MainHand1: staffItem,
    Ring1: ringItem,
  },
});

Available slots:

Head | Shoulders | Chest | Hands | Legs | Waist | Feet
Neck | Ring1 | Ring2
MainHand1 | OffHand1 | MainHand2 | OffHand2
Poison1 | Poison2 | Food | Potion

MainHand1/OffHand1 is the first weapon bar, MainHand2/OffHand2 the second. Which bar is active (for enchants and set bonuses) is controlled by activeWeaponBar (default 1) — see Skills & Passives.

Set bonuses

Set bonuses are derived automatically from the items' setId/setBonus* fields — equipping 5 pieces of a set activates its bonuses as in the UESP editor. You never configure sets manually.

Enchantments

By default the item's own enchantDesc is used. To override an enchantment (e.g. simulating a different enchant choice), use enchantOverrides:

const stats = calculateBuild({
  character: { /* ... */ },
  items: { Head: headItem, Hands: handsItem },
  enchantOverrides: {
    Head:  { enchantDesc: 'Adds up to 868 Maximum Magicka.', enchantName: 'Maximum Magicka Enchantment' },
    Hands: { enchantDesc: 'Adds up to 868 Maximum Magicka.', enchantName: 'Maximum Magicka Enchantment' },
  },
});

The engine applies the correct scaling factor for small slots (Hands/Waist/Feet/Shoulders) itself.

Food & Potions

Use the Food slot with an abilityDesc describing the buff. The engine matches the text against its food rules:

items: {
  Food: {
    itemId: '23274',
    type: '4',
    abilityDesc: 'Increase Max Health by 3094 and Max Magicka by 2856. Magicka Recovery by 315.',
  },
}

The description must match the engine's patterns ("Max Health by N", "Magicka Recovery by N", ...). The safest source of a correct abilityDesc is the UESP item API response for the actual food item.