Best AI for customer service replies / head-to-head

Claude Opus 4.6 vs GPT-5.6 Solfor customer service replies

The verdict

GPT-5.6 Sol wins, 10094

Same 12 customer service replies tasks, marked blind by three rival labs. GPT-5.6 Sol took 3 tasks, Claude Opus 4.6 took 0, 9 tied. Tested 14 Aug 2026.

Where they differed most

The task — The wrong customer

A furious email arrived meant for a different company ('your driver hit my fence' — you sell software). Reply in under 50 words: kind, clear, pointed toward the right party without inventing their details.

Subject: Re: Your Driver Hit My Fence

Hi there,

I'm so sorry about your fence — that sounds really frustrating. However, we're a software company, so this message likely reached us by mistake. I'd recommend checking the original company's contact details (perhaps on a receipt or invoice) to get this resolved quickly.

Wishing you luck!
I’m sorry about the damage and frustration. You’ve reached a software company, and we don’t operate drivers or vehicles. Please check the driver’s paperwork, vehicle details, or your records to identify the responsible company and contact them directly.

Task by task

TaskClaude Opus 4.6GPT-5.6 Sol
Refund the easy way1010
Say no without weasel words1010
Reply to a 1-star review1010
The confused customer1010
De-escalate a threat1010
The feature you won't build910
Apologise for your mistake1010
Price rise notice1010
Outage update mid-incident1010
The wrong customer510
Chargeback rebuttal facts1010
Refuse the fake review request910

Full receipts: Claude Opus 4.6, GPT-5.6 Sol · judges gemini-3.1-pro-preview, gpt-5.6-terra, grok-4.5

Questions people ask

Which is better for customer service replies: Claude Opus 4.6 or GPT-5.6 Sol?

GPT-5.6 Sol — it scored 100/100 against 94/100 on our 12-task customer service replies suite, winning 3 tasks to 0 with 9 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-5.5 vs GPT-5.6 Sol · GPT-5.3-Codex vs GPT-5.6 Sol · GPT-5.6 Sol vs Grok 4.5 · GPT-5.6 Sol vs GPT-5.6 Terra · Gemini 3.1 Pro Preview vs GPT-5.6 Sol · GPT-5.6 Sol vs Qwen3.7 Max

Full ranking: Best AI for customer service replies · model pages: Claude Opus 4.6, GPT-5.6 Sol