Claude Opus 4.6 vs GPT-5.6 Sol for multi-step research
GPT-5.6 Sol wins, 89–85
Same 12 multi-step research tasks, marked blind by three rival labs. GPT-5.6 Sol took 5 tasks, Claude Opus 4.6 took 3, 4 tied. Tested 27 Aug 2026.
Where they differed most
Three sources on GP access in one integrated care board area. Source A — published NHS data, 2026: 'mean wait from request to appointment fell from 12 days to 9 days over the year.' Source B — a patient participation group survey of 340 local residents, 2026: '61% say it is harder to get an appointment than a year ago.' Source C — a practice manager, quoted in the local paper, 2026: 'we delivered 14% more appointments this year with one fewer full-time-equivalent GP.' Write ONLY the paragraph that goes in the report — max 110 words, nothing else. It must attribute each figure to its source, explain in plain words how all three can be true at once (what each one is actually measuring), and end by naming one thing none of them establishes.
The NHS data show that the average recorded wait between booking and appointment shortened from 12 to nine days (Source A), while the practice manager reports that the practice delivered 14 per cent more consultations despite losing one full-time-equivalent GP (Source C). Yet 61 per cent of surveyed residents said access felt harder than the previous year (Source B). These findings are compatible: shorter mean waits and higher volume do not capture how difficult the initial contact is—engaged phone lines, online triage hurdles, or repeated rebo…
Published NHS data for 2026 show that the mean wait from request to appointment fell from 12 to nine days, measuring average elapsed time for recorded appointments. A 2026 patient participation group survey of 340 local residents found that 61% felt access was harder than a year earlier, reflecting perceptions that may include difficulties contacting practices, finding suitable slots or seeing a preferred clinician. A practice manager told the local paper that the practice delivered 14% more appointments with one fewer full-time-equivalent GP,…
Task by task
| Task | Claude Opus 4.6 | GPT-5.6 Sol |
|---|---|---|
| Four numbers, one high street | 9 | 10 |
| The trial that both worked and didn't | 9 | 9 |
| Break the brief into answerable steps | 8 | 10 |
| Corroboration that isn't | 9 | 9 |
| The disagreement is definitional | 8 | 9 |
| A forecast is not an outcome | 10 | 9 |
| The evidence table, as JSON | 5 | 8 |
| Funded, and still the best data | 9 | 9 |
| Write only the limits section | 10 | 9 |
| Not answerable from what you have | 10 | 10 |
| The statistic and the doorstep | 10 | 5 |
| Refuse the manufactured briefing | 5 | 10 |
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 multi-step research: Claude Opus 4.6 or GPT-5.6 Sol?
GPT-5.6 Sol — it scored 89/100 against 85/100 on our 12-task multi-step research suite, winning 5 tasks to 3 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 multi-step research 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 multi-step research head-to-heads: GPT-5.6 Sol vs GPT-5.6 Terra · Claude Opus 4.6 vs GPT-5.6 Terra · GPT-5.3-Codex vs GPT-5.6 Sol · Claude Opus 4.6 vs GPT-5.3-Codex · Claude Sonnet 5 vs GPT-5.6 Sol · Claude Opus 4.6 vs Claude Sonnet 5
Full ranking: Best AI for multi-step research · model pages: Claude Opus 4.6, GPT-5.6 Sol