# ALTCHA and AI agents

ALTCHA is a bot check a site puts in front of its pages or forms. Each site decides where it shows.

Our signed agent met it at 3 products. It stopped our agent at 1 and let it through at 2. Drives from 12 to 24 Oct 2026.

Most stops reflect each site's own settings, not the vendor's defaults.

Source: https://agentdrives.com/vendors/altcha · as data: https://agentdrives.com/vendors/altcha.json · licence CC BY 4.0

- [Brave Search API](https://agentdrives.com/tools/brave.md?via=md): let it through at sign-up, L1 Needs a person, driven 14 Oct 2026
- [Pirsch](https://agentdrives.com/tools/pirsch.md?via=md): stopped it at sign-up, L1 Needs a person, driven 12 Oct 2026
- [Zulip](https://agentdrives.com/tools/zulip.md?via=md): let it through at sign-up, L4 Runs on its own, driven 24 Oct 2026

## What an owner can change

Skip the CAPTCHA for signed agents (valid Web Bot Auth signature), or offer a documented sign-up API.

Where our agent's key stands, vendor by vendor: https://agentdrives.com/method?via=md#our-key
Every vendor: https://agentdrives.com/vendors.md