GPT-5 and Claude 4 are now available

Choosing GPT-5 or Claude 4 from the Biel.ai model dropdown

Update, July 2026: newer models have shipped since this post. See GPT-5.6 Luna and Terra and Claude Sonnet 5 for the current lineup.

GPT-5 and Claude 4 are now available to power your chatbot, on Business plans.

Both are strong at following instructions and reasoning over technical docs, so you can pick the one that fits your content and your budget.

A few ways this plays out:

You run Claude 4 for long, structured reference docs where it tends to stay grounded
You switch to GPT-5 for a snappier feel on shorter, conversational content
You A/B one against the other on your real questions before committing

To switch, open Settings > Chatbot > Model and choose the model. The models docs list what each one is good at.

One tip: change the model, then re-run five or ten of your actual user questions and compare the answers side by side. The right pick depends on your docs, not on the benchmark leaderboard.

Not sure which model fits your docs? Hit reply and we'll help you choose.