Claude Opus 4.8 vs Gemini 3.1 Pro Preview for HR and employment questions
Claude Opus 4.8 wins, 91–87
Same 12 HR and employment questions tasks, marked blind by three rival labs. Claude Opus 4.8 took 6 tasks, Gemini 3.1 Pro Preview took 2, 4 tied. Tested 18 Aug 2026.
Where they differed most
Guidance excerpt: 'A fair grievance procedure normally follows these stages: the employee sets out the grievance in writing; the employer holds a meeting to discuss it without unreasonable delay; the employee has a statutory right to be accompanied at that meeting by a colleague or a trade union representative; the employer decides what action to take and confirms the decision to the employee in writing; and the employee is told they may appeal, with the appeal heard by someone not previously involved wherever possible. Written records should be kept at every stage.' Priya has submitted a grievance about her own line manager, Dean — who is the person who would normally hold the meeting. Using only the excerpt, set out the first 5 steps in order: exactly 5 bullets, one line each, no sub-points, no preamble. On the line where it matters, say what Dean's involvement changes and who should act instead.
- Priya sets out her grievance in writing. - The employer holds a meeting to discuss it without unreasonable delay — since the grievance is about Dean, he should not hold the meeting; someone else should act instead. - Priya may be accompanied at that meeting by a colleague or a trade union representative. - The employer decides what action to take and confirms the decision to Priya in writing. - Priya is told she may appeal, with the appeal heard by someone not previously involved wherever possible.
* Priya sets out the grievance in writing, and a written record is kept. * The employer holds a meeting to discuss it without unreasonable delay, keeping a written record; because the grievance is about Dean, his involvement means he cannot hold the meeting, and the employer (or someone not previously involved) must act instead. * Priya exercises her statutory right to be accompanied at that meeting by a colleague or a trade union representative, and a written record is kept. * The employer decides what action to take and confirms the decision…
Task by task
| Task | Claude Opus 4.8 | Gemini 3.1 Pro Preview |
|---|---|---|
| Probation is not a free pass | 8 | 9 |
| Write only the message | 10 | 10 |
| The grievance about the manager | 9 | 7 |
| The decision was made in the car | 10 | 9 |
| Ask everyone or ask nobody | 8 | 8 |
| The off-the-record phone call | 9 | 8 |
| Write only the invitation letter | 10 | 10 |
| Precedent is not a reason | 9 | 8 |
| Write only the file note | 10 | 10 |
| The number you must not supply | 10 | 8 |
| The screenshotted group chat | 6 | 8 |
| Refuse the engineered redundancy | 10 | 9 |
Full receipts: Claude Opus 4.8, Gemini 3.1 Pro Preview · judges gemini-3.1-pro-preview, gpt-5.6-terra, grok-4.5
Questions people ask
Which is better for HR and employment questions: Claude Opus 4.8 or Gemini 3.1 Pro Preview?
Claude Opus 4.8 — it scored 91/100 against 87/100 on our 12-task HR and employment questions suite, winning 6 tasks to 2 with 4 tied. Every answer was marked blind by three judges from three rival AI labs.
How was this tested?
Both models answered the identical published HR and employment questions tasks. Three AI judges from three different labs scored every answer blind against a fixed rubric; mechanically checkable rules (word limits, banned phrases) are enforced by the test harness in code. The raw outputs and judge verdicts are downloadable.
More HR and employment questions head-to-heads: Claude Opus 4.8 vs Claude Sonnet 5 · Claude Sonnet 5 vs Gemini 3.1 Pro Preview · Claude Opus 4.8 vs GPT-5.5 · Gemini 3.1 Pro Preview vs GPT-5.5 · Claude Opus 4.8 vs GPT-5.6 Sol · Gemini 3.1 Pro Preview vs GPT-5.6 Sol
Full ranking: Best AI for HR and employment questions · model pages: Claude Opus 4.8, Gemini 3.1 Pro Preview