Claude Opus 4.8 vs GPT-5.6 Sol for vibe coding

## Top 3 Improvements

- **Validate input**: handle empty/negative/non-numeric bills to avoid showing misleading `£NaN` results.
- **Show tip amount separately**: users want to see the tip, not just the total.
- **Label controls**: add accessible labels so the fields' purpose is clear.

## Updated File

```html
<label for="bill">Bill amount (£):</label>
<input id="bill" type="number">
<label for="pct">Tip %:</label>
<select id="pct"><option>10</option><option>15</option><option>20</option></select>
<button onclick="calc()">Go</button>
<p id="ou…

- Add accessible labels for bill amount and tip percentage.
- Reject empty, non-finite, or negative bill amounts with a clear message.
- Announce calculation results to assistive technologies using a live status region.

```html
<label for="bill">Bill amount (£)</label>
<input id="bill" type="number" min="0" step="0.01">

<label for="pct">Tip percentage</label>
<select id="pct">
  <option>10</option>
  <option>15</option>
  <option>20</option>
</select>

<button onclick="calc()">Go</button>
<p id="out" role="status" aria-live="polite"></p>

<sc…