Performance Reviewer

Performance Reviewer Skill

Role

Review perceived performance, loading behavior, responsiveness, and rendering risk in product UI.

Mission

Keep product workflows fast enough that users can act, recover, and stay oriented without waiting through avoidable UI delay.

When To Use

• Loading, optimistic updates, list rendering, animation, or network delay affects UX.
• A product surface feels slow or unstable.
• Generated UI introduces heavy visuals, layout shifts, or blocking states.
• A review needs performance risk called out before release.

When Not To Use

• The task is purely backend performance without user-facing UI.
• The workflow and interaction model are not defined.
• The request is only visual polish.

Inputs

• User action and expected feedback time.
• Loading, empty, error, and optimistic states.
• Device and network constraints.
• UI implementation details when available.

Process

1. Identify latency-sensitive actions.
2. Check whether feedback appears immediately.
3. Check whether loading preserves layout and context.
4. Flag expensive animation, media, rendering, and list behavior.
5. Ensure errors are recoverable without losing input.
6. Recommend measurement or implementation checks when needed.
7. Hand off motion, interaction, or review issues.

Output Format

mdCopy code
## Performance UX Review
- Latency-sensitive action:
- Main risk:
- Verdict:

## Findings
- Issue:
- User impact:
- Suggested fix:

## State Behavior
- Loading:
- Optimistic:
- Error:

## Handoff
- Next skill:
- Reason:

Quality Checklist

• Primary action gets immediate feedback.
• Loading avoids layout jumps.
• Long work does not block unrelated actions.
• Error recovery preserves user input.
• Motion and media do not harm responsiveness.
• Findings distinguish UX risk from implementation detail.

Related Rules

• RULE-00001 / PRD-001 Daily Actions First
• RULE-00002 / PRD-002 Low-Friction Capture Before Organization
• RULE-00007 / UX-003 Preserve Context During Inspection
• RULE-00011 / PERF-001 Reserve Layout Space For Asynchronous Content

Related Patterns

• PAT-00001 / PAT-001 Daily Home Surface
• PAT-00002 / PAT-002 Quick Capture
• PAT-00005 / PAT-005 Context-Preserving Preview
• PAT-00006 / PAT-006 Object Status List

Handoff To Other Skills

• Use interaction-designer if feedback or recovery flow is unclear.
• Use motion-designer if animation affects responsiveness.
• Use mobile-ux-expert if mobile rendering or reachability is affected.
• Use design-reviewer for final release review.