state-safety-action-creator-guard

name	state-safety-action-creator-guard
description	enforce state immutability and valid transitions. Trigger when modifying the reducer, creating actions, or debugging state bugs.

State Safety & Action Creator Guard

Ensure global state remains consistent, immutable, and valid.

Workflow

1. Use Action Creators

   • Rule: Never dispatch raw objects (dispatch({ type: 'FOO' })).
   • Fix: Import from src/context/actionCreators.ts.
   • Cross-check: Verify reducer handling in src/context/gameReducer.ts.
   • Why: Centralizes logic and ensures payload shape.

2. Enforce Invariants

   • Money: Must be >= 0.
   • Harmony: Must be > 0 (or triggers Game Over).
   • Inventory: Items must be unique IDs.

3. Check Reducer Logic

   • Immutability: Use spread syntax ...state or immer (if available).
   • Clamping: Math.max(0, newState.money).

Example

Input: "Deduct 50 money for the venue fee."

Bad:

dispatch({ type: 'DEDUCT_MONEY', amount: 50 })

Good:

import { createUpdatePlayerAction } from 'src/context/actionCreators'

if (player.money >= 50) {
  // Use createUpdatePlayerAction with object payload
  dispatch(createUpdatePlayerAction({ money: Math.max(0, player.money - 50) }))
} else {
  console.error('Insufficient funds')
}

Reducer Check:

case 'UPDATE_PLAYER':
  return {
    ...state,
    player: {
      ...state.player,
      ...action.payload
    }
  };

Output: "Updated dispatch to use createUpdatePlayerAction with validation check player.money >= 50."

Skill sync: compatible with React 19.2.6 / Vite 8.0.10 / Tailwind 4.2.4 baseline as of 2026-05-20.