SKILL.md
Physics Reference
Detailed physics tables for the crafting skill. Loaded on-demand.
The Complete Physics Table
| Effect | Sync | Timing | Confirmation | Easing | Spring |
|---|---|---|---|---|---|
| Financial | Pessimistic | 800ms | Required | ease-out | 200/30 |
| Destructive | Pessimistic | 600ms | Required | ease-out | 200/30 |
| Soft Delete | Optimistic | 200ms | Toast+Undo | spring | 500/30 |
| Standard | Optimistic | 200ms | None | spring | 500/30 |
| Navigation | Immediate | 150ms | None | ease | — |
| Local State | Immediate | 100ms | None | spring | 700/35 |
Timing Rationale
800ms (Financial)
Time needed for users to:
- Read and verify the amount
- Mentally commit to the action
- Feel the weight of irreversibility
Faster = anxiety. Slower = sluggish. 800ms is calibrated.
600ms (Destructive)
Permanent deletion needs deliberation but less than money. Warning color + timing = sufficient gravity.
200ms (Standard)
Research shows 200ms is perceived as "instant" while allowing visual feedback.
- <100ms: Users miss the confirmation
- >300ms: Feels laggy
100ms (Local)
No network latency to hide. Users expect immediate response. Any delay feels broken.
Sync Strategy Details
Pessimistic
User clicks → Loading state → Server confirms → UI updates- Never show success before server confirms
- Cancel button always visible during loading
- Error state has clear recovery path
Optimistic
User clicks → UI updates immediately → Server confirms (or rollback)- Requires
onMutatefor immediate update - Requires
onErrorfor rollback - User sees instant feedback
Immediate
User clicks → UI updates → No server call- Pure client state (theme, toggles)
- useState or context only
- Zero loading states