Claude Sonnet 5 vs GPT-5.6 Terra for everyday legal questions

The verdict

GPT-5.6 Terra wins, 9388

Same 12 everyday legal questions tasks, marked blind by three rival labs. GPT-5.6 Terra took 5 tasks, Claude Sonnet 5 took 1, 6 tied. Tested 16 Aug 2026.

Where they differed most

The task — Eight-month-old washing machine

A washing machine bought 8 months ago from a UK retailer has died. The retailer says 'out of our hands, contact the manufacturer'. Explain who the contract is actually with and what UK consumer law expects of goods (satisfactory quality, durability), what changes now it is month 8 rather than month 5, and then draft the firm, courteous email to the retailer — the law may be named, the tone must stay civil.

# Who You're Actually Dealing With

The retailer is wrong (or hoping you don't know better). Under UK law, **your contract is with the retailer**, not the manufacturer. You paid the retailer; they sold you the goods; they are legally responsible for them. The manufacturer's warranty is a *separate, additional* promise — it doesn't replace or override your statutory rights against the seller. "Contact the manufacturer" is not a legally valid response to a faulty goods complaint, and a retailer cannot contract out of the Consumer Rights Act 2015.…
In UK law, your contract is with the **retailer who sold you the washing machine**, not the manufacturer. The retailer cannot simply say that it is “out of our hands” and require you to deal with the manufacturer.

A manufacturer’s warranty may be useful and can sometimes provide a quicker route, but it is **additional to**, not a replacement for, your statutory rights against the retailer.

Under the **Consumer Rights Act 2015**, goods supplied by a retailer must be:

- **Of satisfactory quality** — meeting the standard a reasonable person wou…

Task by task

TaskClaude Sonnet 5GPT-5.6 Terra
Landlord with a key98
The unprotected deposit99
Eight-month-old washing machine610
The scary parking letter89
Translate the clause910
The hedge war99
Hours cut overnight99
The handwritten will99
£600 and a shrug99
It depends what you signed910
Letter before action910
Refuse the order workaround1010

Full receipts: Claude Sonnet 5, GPT-5.6 Terra · judges gemini-3.1-pro-preview, gpt-5.6-terra, grok-4.5

Questions people ask

Which is better for everyday legal questions: Claude Sonnet 5 or GPT-5.6 Terra?

GPT-5.6 Terra — it scored 93/100 against 88/100 on our 12-task everyday legal questions 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 everyday legal 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 everyday legal questions head-to-heads: Claude Opus 4.8 vs GPT-5.6 Terra · Claude Opus 4.8 vs Claude Sonnet 5 · GPT-5.6 Sol vs GPT-5.6 Terra · Claude Sonnet 5 vs GPT-5.6 Sol · GPT-5.3-Codex vs GPT-5.6 Terra · GPT-5.5 vs GPT-5.6 Terra

Full ranking: Best AI for everyday legal questions · model pages: Claude Sonnet 5, GPT-5.6 Terra