Best AI for customer service replies / head-to-head
Gemini 3.5 Flash vs Grok 4.5for customer service replies
Grok 4.5 wins, 98–94
Same 12 customer service replies tasks, marked blind by three rival labs. Grok 4.5 took 5 tasks, Gemini 3.5 Flash took 1, 6 tied. Tested 14 Aug 2026.
Where they differed most
A paying customer asks when dark mode is coming; it is not on the roadmap. Reply in under 80 words: honest no-date answer, why in one sentence, what they CAN do now if anything, and log-their-vote phrasing that is not a brush-off.
To be transparent, we don't have a release date for dark mode as it isn't on our current roadmap. Right now, our development team is focusing on critical performance and security upgrades. In the meantime, you can use a browser extension like Dark Reader to view our site in dark mode. I have officially logged your request with our product team to help us prioritize this for future planning.
**Here's a concise reply you can send:** --- Thanks for asking! Dark mode isn’t on the roadmap right now—we’re prioritizing higher-impact features based on broader customer feedback. In the meantime you can use a browser extension or OS-level dark theme for a similar effect. I’ve logged your vote for it; we review these regularly when planning what’s next. --- (58 words)
Task by task
| Task | Gemini 3.5 Flash | Grok 4.5 |
|---|---|---|
| Refund the easy way | 10 | 10 |
| Say no without weasel words | 10 | 10 |
| Reply to a 1-star review | 10 | 10 |
| The confused customer | 9 | 10 |
| De-escalate a threat | 8 | 9 |
| The feature you won't build | 10 | 8 |
| Apologise for your mistake | 10 | 10 |
| Price rise notice | 10 | 10 |
| Outage update mid-incident | 9 | 10 |
| The wrong customer | 8 | 10 |
| Chargeback rebuttal facts | 10 | 10 |
| Refuse the fake review request | 9 | 10 |
Full receipts: Gemini 3.5 Flash, Grok 4.5 · judges claude-sonnet-5, gpt-5.6-terra, grok-4.5
Questions people ask
Which is better for customer service replies: Gemini 3.5 Flash or Grok 4.5?
Grok 4.5 — it scored 98/100 against 94/100 on our 12-task customer service replies suite, winning 5 tasks to 1 with 6 tied. Every answer was marked blind by three judges from three rival AI labs.
How was this tested?
Both models answered the identical published customer service replies 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 customer service replies head-to-heads: GPT-5.6 Sol vs Grok 4.5 · Gemini 3.5 Flash vs GPT-5.6 Sol · GPT-5.5 vs Grok 4.5 · Gemini 3.5 Flash vs GPT-5.5 · GPT-5.3-Codex vs Grok 4.5 · Gemini 3.5 Flash vs GPT-5.3-Codex
Full ranking: Best AI for customer service replies · model pages: Gemini 3.5 Flash, Grok 4.5