Before paying for an AI assistant, give it a task you already do and check how much work the answer still needs. A polished social post is little help if it promises something your business doesn't offer.
What the three tests showed
The tests used a fictional product photography studio in Zagreb, Croatia. On September 17, 2026, OpenAI gpt-5.6-sol, Anthropic claude-sonnet-5 and Google gemini-3.8-flash each answered three identical Croatian prompts once, producing nine responses.
| Task | GPT | Claude | Gemini |
|---|---|---|---|
| Short social post | Kept the stated package scope | Added customer choice of backgrounds | Kept the stated package scope |
| Inquiry totals | Correct counts and accepted values | Correct figures; exceeded the word limit | Correct counts and accepted values |
| Marketing plan | Fit the weekly time allowance | Fit the time allowance; exceeded the word limit | Fit the time allowance; assumed email-open tracking |
The models were accessed through DataForSEO, a service that lets software send them questions. This tested their answers rather than the ChatGPT, Claude or Gemini apps. Each used its default settings, with no web search, earlier conversation or second attempt. The model names can refer to different versions over time. Nine answers can't establish a ranking or reliability with English or larger files, and they don't tell you which features an app account includes.
A small addition can change your offer
The first task asked for a social post offering eight photographs, two backgrounds and one revision round. No price or delivery time was supplied. Here is the original Croatian prompt translated into English:
Sjena is a fictional photography studio in Zagreb that photographs small products. The package includes 8 photos, 2 backgrounds and 1 round of revisions. No price or turnaround time has been specified. Write a Croatian social post of no more than 70 words, using formal address and one call to action asking the customer to send a product list. Do not invent a price, deadline, reviews or guarantees. No emojis or hashtags.
All three answers kept the package numbers and stayed within the word limit. Claude added a promise that customers could choose the backgrounds, which the brief hadn't offered.
The fix is short. Both versions below are translated from Croatian:
- Original: “2 backgrounds of your choice”.
- Revised: “2 backgrounds”.
A customer reading that post could expect to choose the backgrounds. Check promises and extras as carefully as prices and quantities.
Here is the full edited post in English. It translates an editorial revision made for this article, rather than a model response or an approved business offer:
Sjena photographs small products in Zagreb. The package includes 8 photos, 2 backgrounds and 1 round of revisions. Send your product list for a quote.
Check what a total actually means
The second task supplied five rows of customer inquiries, including a duplicate. Two offers had been accepted: €200 from an Instagram inquiry and €300 from a referral. Another €150 Instagram offer had been rejected, and a €400 website offer was still pending.
All three models correctly counted four unique inquiries. The value of accepted offers was also correct: €200 + €300 = €500. The duplicate counts once; rejected and pending offers stay out of that total.
The €500 is accepted work, with payment unconfirmed. All three answers kept that distinction and declined to calculate return on investment without the missing cost and return information.
When you try this with your own figures, define the statuses first. Then check duplicates and totals independently, in a spreadsheet or by hand.
A plan must fit more than your calendar
All three two-week marketing plans fit the two-hour weekly allowance, included a review and deferred paid ads. The brief asked them to attract relevant inquiries from small online stores.
Every plan assumed portfolio work was ready to share and suggested outreach without checking that the studio had a suitable channel. Gemini also assumed email-open tracking was available. The prompt hadn't prohibited outreach; the problem was the missing context.
When requesting a plan, state which channels you use and what work you can share. An editorial alternative for this fictional studio would be to check the contact link on one approved portfolio example, publish it through an existing suitable channel and record inquiries, including zero. No plan was carried out, so no marketing outcome was measured.
The plans also had a 120-word limit. Including headings and numbers, the saved counter returned 123 for GPT, 152 for Claude and 108 for Gemini. GPT's small overrun depends on how compound words are counted. Claude also exceeded the calculation task's 100-word limit.
Run a small trial before paying
Choose one recurring task and try it in an assistant you already have. Free access, if available on your account, may be enough for this first check. Use fictional or suitably anonymized information you're permitted to share, and check the account's data terms.
Keep a short record:
| Record | What to save |
|---|---|
| Task | Date, app, model shown and exact prompt |
| What it must get right | Business facts, expected totals or available time |
| What needed fixing | Original answer, unsupported additions and your edits |
| Decision | Use after review, or reject |
Compare how much correction and checking each answer needs, then repeat with another recurring task before choosing an assistant.
The nine API calls cost $0.048928 in total, about five US cents including the intermediary fee. OpenAI, Anthropic and Google publish their API prices. API usage and app subscriptions are separate purchases; check the price and features of the plan you're considering before paying.
Mischka Studio's paid Marketing Guide, available in Croatian, includes eight AI drafting generators in its Professional plan. They weren't part of these tests, and their drafts need the same review and editing before use.
