Nexxtool AI

Nexxtool AI checks every AI reply against the rules you set and returns pass or block with the reason. It is one API call, and it works with any AI that writes text.

What it does

You make one call: POST /v1/validate. Send the reply your AI wrote and the rules it has to follow. You get back a pass or block verdict, a 0–1 score, and the specific reasons (one entry per problem found). Every result is logged so you can review it in the dashboard.

Rules you can set:

• Banned words and phrases — must_not_contain.
• Required words and phrases — must_contain.
• Length — min_length and max_length.
• Patterns — must_match regular expressions.
• Structure — for example valid JSON with the fields you require.
• Leftover AI text — like ‘Here’s a more polished version…’ accidentally sent to a customer.

See the Rule Sets reference for every option.

Keys and limits

You authenticate with an API key from the dashboard. Each plan has a monthly check cap and a per-second rate limit per key. The Free plan is permanent: 1,000 checks a month and 10 requests per second. Paid plans raise both. See Pricing for the full table and Errors & rate limits for how limits are reported.

Get started

1. Sign in to the dashboard with your Nexxtool AI account.
2. Create an API key.
3. Follow the Quickstart to send your first check.