Vercel customer_verification_required for Jev
Last checked · Independent guide, not affiliated with TypeSafe AI
customer_verification_required is Vercel AI Gateway's error for a team that has not verified a payment method. Jev falls under the free tier, but the free credit only unlocks after you add a card to the Vercel team. Adding a card is enough: you do not need to buy credits, and buying them ends the monthly free credit.
When you see it
Section titled “When you see it”This error comes from Vercel, not from TypeSafe. We ran into it on September 18, 2026 when we first called Jev (typesafe-ai/jev) through Vercel AI Gateway with the AI SDK’s experimental_evaluate, from a Vercel team that had no payment method. The request failed immediately with an error whose code was customer_verification_required, and the message pointed at adding a credit card.
It appears even though:
- Jev is available on Vercel’s free tier, and every team gets $5 of AI Gateway credit per month.
- On September 19, 2026, Vercel listed Jev’s input and output as free under a promotion running until September 25, 2026.
Free still requires a verified customer. Vercel uses the card to confirm the team is a real customer before releasing free credit.
How to fix it
Section titled “How to fix it”- In the Vercel dashboard, open the team that owns your AI Gateway key.
- Add a payment card to the team’s billing settings.
- Call Jev again with the same key. No new key is needed.
That is all. After the card was added, our requests went through on the free tier.
Do not buy credits by accident
Section titled “Do not buy credits by accident”Adding a card and buying credits are different steps. Vercel’s pricing documentation says that purchasing AI Gateway credits moves your team to the paid tier. The paid tier has higher rate limits, but the monthly free credit stops. If you only want to try Jev, add the card and stop there. In the AI Gateway dashboard, the top-up option sits behind the balance button at the top right.
What to expect next: the free-tier throttle
Section titled “What to expect next: the free-tier throttle”Once verified, the next thing most people hit is the free tier’s per-model rate limit. In our testing it let a few Jev questions through and then throttled requests for a while, so a 131-question batch took about an hour and a half. For batch work, space requests out or move to the paid tier deliberately. See 429 Too Many Requests.
Code check
Section titled “Code check”Make sure the error is not coming from somewhere else first. The call should look like this:
import { experimental_evaluate as evaluate } from 'ai';
const result = await evaluate({ model: 'typesafe-ai/jev', state: 'Is this message a complaint? The app deleted my draft twice today.', questions: { complaint: { type: 'boolean', instructions: 'Is the user complaining?' }, },});The key must be an AI Gateway key (AI_GATEWAY_API_KEY), and the AI SDK version must support experimental_evaluate (version 7 or later).
Avoiding the Vercel route
Section titled “Avoiding the Vercel route”If you cannot or do not want to put a card on a Vercel team, the same model is available on OpenRouter with prepaid credits, on Cloudflare Workers AI, and on TypeSafe’s own API once your account is let in. See How to get a Jev API key and Jev on Vercel AI Gateway.