# MagicItemReaction

> Kinbarrow modding reference — content tree `4a103dcdb658a75a`, version `0.2.0+main.e011511f4`.

[Effects and mechanisms](https://kinbarrow.com/modding/latest/mechanisms.md)

Used by [MagicItem](https://kinbarrow.com/modding/latest/magic-item.md#magic-item-reaction).

This is a nested shape inside a content file. The catalog explains context validation and links real RON examples.

Reusable, explicitly chosen Reaction projected by one active item source.

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `charge_cost` | `uint8` | required | Charges paid by the concrete source item only after acceptance. Zero is valid for reactions whose limiter is only the creature's Reaction. |
| `effect` | `MagicItemReactionEffect` | required | Authored effect. |
| `requires` | `ItemModeRequirement` | required | Custody/equipment state required at both offer and acceptance. |
| `requires_free_hand` | `boolean` | required | The bearer must have a free hand both when this Reaction is offered and when it is accepted. |
| `trigger` | `MagicItemReactionTrigger` | required | Authored trigger. |


## Supporting shapes

- [ItemModeRequirement](https://kinbarrow.com/modding/latest/mechanisms/magic-item/item-mode-requirement.md)
- [MagicItemReactionEffect](https://kinbarrow.com/modding/latest/mechanisms/magic-item/magic-item-reaction-effect.md)
- [MagicItemReactionTrigger](https://kinbarrow.com/modding/latest/mechanisms/magic-item/magic-item-reaction-trigger.md)