Gemini 3.1 Pro Preview vs GPT-5.6 Sol for workflow automation

The verdict

GPT-5.6 Sol wins, 9283

Same 12 workflow automation tasks, marked blind by three rival labs. GPT-5.6 Sol took 7 tasks, Gemini 3.1 Pro Preview took 0, 5 tied. Tested 18 Aug 2026.

Where they differed most

The task — Where the human stays

A 40-person UK company wants to automate expense reimbursement end to end: receipt photographed, read, categorised, approved, paid into the employee's bank account, posted to the ledger. The finance director's brief is 'no human touches it under £100'. Go through the process and mark, for each stage, whether it can be automated, automated with a check, or must stay with a person — and give the reason in terms of what goes wrong, not in terms of policy. Name the two stages where full automation would be genuinely dangerous for a company this size, and say what the cheapest sufficient control is at each: not the most thorough control, the cheapest one that actually catches the thing.

Here is the breakdown of the end-to-end expense process for a 40-person UK company, keeping the Finance Director’s "no human touches it under £100" brief in mind. 

### Part 1: The Process Stages

**1. Receipt Photographed & Submitted**
*   **Status:** Automated.
*   **What goes wrong:** The employee takes a blurry photo, photographs a credit card terminal receipt instead of the itemised VAT receipt, or uploads the same receipt twice. 

**2. Read / OCR (Data Extraction)**
*   **Status:** Automated with a check.
*   **What goes wrong:** The soft…
A £100 threshold is not a useful safety boundary by itself: duplicate or personal claims can be kept at £99 or split into several lines. Controls should therefore aggregate by employee, merchant and period.

### End-to-end assessment

| Stage | Treatment | What can go wrong |
|---|---|---|
| 1. Employee captures and submits receipt | **Automated** | The app can require a live photo or original electronic receipt, check image quality and reject unreadable or incomplete images. The employee must correct failures, but finance need not touch them.…

Task by task

TaskGemini 3.1 Pro PreviewGPT-5.6 Sol
The MOT reminder nobody sends89
The spec, as JSON89
Where the human stays69
The unhappy paths are the job99
Do not automate this99
It fired twice99
The spreadsheet that runs the business89
The alert that wakes someone up1010
How long it really takes89
No API, no chance?810
Rules, not guesses88
Refuse the scraper910

Full receipts: Gemini 3.1 Pro Preview, GPT-5.6 Sol · judges claude-sonnet-5, gpt-5.6-terra, grok-4.5

Questions people ask

Which is better for workflow automation: Gemini 3.1 Pro Preview or GPT-5.6 Sol?

GPT-5.6 Sol — it scored 92/100 against 83/100 on our 12-task workflow automation suite, winning 7 tasks to 0 with 5 tied. Every answer was marked blind by three judges from three rival AI labs.

How was this tested?

Both models answered the identical published workflow automation 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 workflow automation head-to-heads: Claude Sonnet 5 vs GPT-5.6 Sol · GPT-5.5 vs GPT-5.6 Sol · GPT-5.6 Sol vs Grok 4.5 · GPT-5.6 Sol vs Kimi K3 · Claude Opus 4.8 vs GPT-5.6 Sol · GLM 5.2 vs GPT-5.6 Sol

Full ranking: Best AI for workflow automation · model pages: Gemini 3.1 Pro Preview, GPT-5.6 Sol