Change a Crafting Recipe

Items carry a top-level "Recipe" object that sets craft time, knowledge gate, inputs, and bench. You can tune one field, fully redesign the ingredient list, or bolt on a single extra ingredient. The trick is knowing when arrays replace and when they append.

Goal

Make the iron sword faster and cheaper to craft. First version: drop the time and strip the recipe down to a few iron bars. Second version: keep the stock recipe but add one more ingredient.

The Asset

Server/Item/Items/Weapon/Sword/Weapon_Sword_Iron.json

{
  "Parent": "Template_Weapon_Sword",
  "TranslationProperties": {
    "Name": "server.items.Weapon_Sword_Iron.name"
  },
  "Model": "Items/Weapons/Sword/Iron.blockymodel",
  "Texture": "Items/Weapons/Sword/Iron_Texture.png",
  "Quality": "Uncommon",
  "Icon": "Icons/ItemsGenerated/Weapon_Sword_Iron.png",
  "ItemLevel": 20,
  "Recipe": { // you only want to tweak fields inside this block
    "TimeSeconds": 3.5,
    "KnowledgeRequired": false,
    "Input": [
      {
        "ItemId": "Ingredient_Bar_Iron",
        "Quantity": 6
      },
      {
        "ItemId": "Ingredient_Leather_Light",
        "Quantity": 3
      },
      {
        "ItemId": "Ingredient_Fabric_Scrap_Linen",
        "Quantity": 3
      }
    ],
    "BenchRequirement": [
      {
        "Type": "Crafting",
        "Categories": [
          "Weapon_Sword"
        ],
        "Id": "Weapon_Bench"
      }
    ]
  },
  "InteractionVars": {
    "Swing_Left_Damage": {
      "Interactions": [
        {
          "Parent": "Weapon_Sword_Primary_Swing_Left_Damage",
          "DamageCalculator": {
            "BaseDamage": {
              "Physical": 10
            }
          },
          "DamageEffects": {
            "WorldSoundEventId": "SFX_Sword_T2_Impact",
            "LocalSoundEventId": "SFX_Sword_T2_Impact"
          }
        }
      ]
    },
    "Swing_Right_Damage": {
      "Interactions": [
        {
          "Parent": "Weapon_Sword_Primary_Swing_Right_Damage",
          "DamageCalculator": {
            "BaseDamage": {
              "Physical": 10
            }
          },
          "DamageEffects": {
            "WorldSoundEventId": "SFX_Sword_T2_Impact",
            "LocalSoundEventId": "SFX_Sword_T2_Impact"
          }
        }
      ]
    },
    "Swing_Down_Damage": {
      "Interactions": [
        {
          "Parent": "Weapon_Sword_Primary_Swing_Down_Damage",
          "DamageCalculator": {
            "BaseDamage": {
              "Physical": 18
            }
          },
          "DamageEffects": {
            "WorldSoundEventId": "SFX_Sword_T2_Impact",
            "LocalSoundEventId": "SFX_Sword_T2_Impact"
          }
        }
      ]
    },
    "Thrust_Damage": {
      "Interactions": [
        {
          "Parent": "Weapon_Sword_Primary_Thrust_Damage",
          "DamageCalculator": {
            "BaseDamage": {
              "Physical": 26
            }
          },
          "EntityStatsOnHit": [
            {
              "EntityStatId": "SignatureEnergy",
              "Amount": 3
            }
          ],
          "DamageEffects": {
            "WorldSoundEventId": "SFX_Sword_T2_Impact",
            "LocalSoundEventId": "SFX_Sword_T2_Impact"
          }
        }
      ]
    },
    "Vortexstrike_Spin_Damage": {
      "Interactions": [
        {
          "Parent": "Weapon_Sword_Signature_Vortexstrike_Spin_Damage",
          "DamageCalculator": {
            "BaseDamage": {
              "Physical": 19
            }
          },
          "EntityStatsOnHit": [],
          "DamageEffects": {
            "WorldSoundEventId": "SFX_Sword_T2_Impact",
            "LocalSoundEventId": "SFX_Sword_T2_Impact"
          }
        }
      ]
    },
    "Vortexstrike_Stab_Damage": {
      "Interactions": [
        {
          "Parent": "Weapon_Sword_Signature_Vortexstrike_Stab_Damage",
          "DamageCalculator": {
            "BaseDamage": {
              "Physical": 56
            }
          },
          "EntityStatsOnHit": [],
          "DamageEffects": {
            "WorldSoundEventId": "SFX_Sword_T2_Impact",
            "LocalSoundEventId": "SFX_Sword_T2_Impact"
          }
        }
      ]
    },
    "Guard_Wield": {
      "Interactions": [
        {
          "Parent": "Weapon_Sword_Secondary_Guard_Wield",
          "StaminaCost": {
            "Value": 10,
            "CostType": "Damage"
          }
        }
      ]
    }
  },
  "MaxDurability": 120,
  "DurabilityLossOnHit": 0.21
}

Recipe is an object. Recipe.Input and Recipe.BenchRequirement are arrays.

The patch

Server/Item/Items/Weapon/Sword/Weapon_Sword_Iron.patch:

{
  "Recipe": {
    "TimeSeconds": 2.0,
    "Input": [
      { "ItemId": "Ingredient_Bar_Iron", "Quantity": 3 }
    ]
  }
}

After

• Recipe.TimeSeconds becomes 2.0. The Recipe object merges, so the scalar is overwritten in place.
• Recipe.Input is REPLACED with the single new entry. The recipe now costs 3 iron bars and nothing else. The leather and fabric are gone, because restating an array drops everything you did not write.
• Recipe.KnowledgeRequired and Recipe.BenchRequirement survive untouched. You did not name them, so the merge leaves them alone.

{
  "Recipe": {
    "TimeSeconds": 2.0,
    "KnowledgeRequired": false,
    "Input": [
      { "ItemId": "Ingredient_Bar_Iron", "Quantity": 3 }
    ],
    "BenchRequirement": [
      { "Type": "Crafting", "Categories": [ "Weapon_Sword" ], "Id": "Weapon_Bench" }
    ]
  }
}

Add one ingredient, keep the originals

If you only want to bolt on an extra input without rewriting the list, suffix the key with + to append:

{
  "Recipe": {
    "Input+": [
      { "ItemId": "Ingredient_Bar_Iron", "Quantity": 2 }
    ]
  }
}

After this, all three stock inputs survive and the extra 2 iron bars are appended to the end. The recipe now has four input entries.

Notes

• The core rule is the array rule. Restating Input REPLACES the whole ingredient list. Use that to fully redesign a recipe. Input+ APPENDS to it. Use that to add one ingredient on top of the originals.
• The same applies to BenchRequirement. Restating it swaps the bench; + adds a second bench requirement.
• Object fields like TimeSeconds and KnowledgeRequired merge in place, so you can change one and leave the rest. Only the keys you name are touched.
• To make the item uncraftable instead, delete the whole Recipe with null. See Removing-Values.
• If more than one mod edits the same recipe, $Priority decides last-wins. See the syntax reference and the Pack Developers guide.