# YandexAdditionalBot

> The second token Yandex publishes for the same AI-answers opt-out. Both names appear in Yandex's own robot list, so a robots.txt that names only one of them is half a policy.

| field | value |
|---|---|
| operator | Yandex |
| category | AI training crawlers |
| robots.txt token | `YandexAdditionalBot` |
| user-agent contains | `YandexAdditionalBot` |
| robots.txt | ignores the * group; obeys rules named for its own token |
| verify by | reverse DNS |
| published IP ranges | none published |
| prefixes mirrored | 0 IPv4 / 0 IPv6 |
| operator docs | https://yandex.com/support/webmaster/en/robot-workings/check-yandex-robots |
| last reviewed | 2026-09-01 |

## What blocking it costs you

Same as YandexAdditional: out of Yandex's AI answers, still in Yandex Search. Name both tokens or neither.

## Full user-agent string

```
Mozilla/5.0 (compatible; YandexAdditionalBot/1.0; +http://yandex.com/bots)
```

## Block it

```
User-agent: YandexAdditionalBot
Disallow: /
```

## Allow it

```
User-agent: YandexAdditionalBot
Allow: /
```

JSON: https://www.pathwren.workers.dev/crawler/yandexadditionalbot.json · index: https://www.pathwren.workers.dev/llms.txt