Safe Google Bots

Google-Agent

Q: What is the official user-agent string for Google-Agent?

Google-Agent has two user-agent strings: a mobile variant (Mozilla/5.0 ...compatible; Google-Agent...) and a desktop variant (Mozilla/5.0 AppleWebKit/537.36 ...compatible; Google-Agent...). Both include a link to Google's documentation.

Q: Is Google-Agent safe?

Yes, Google-Agent is safe and legitimate. It is operated by Google and only acts when triggered by a real user via products like Project Mariner.

Q: Will blocking Google-Agent hurt my SEO?

No. Blocking Google-Agent does not affect your search rankings. It is a user-triggered agentic bot, not a search indexer.

Q: What is the difference between Google-Agent and Googlebot?

Googlebot indexes pages for Google Search. Google-Agent navigates sites and takes actions (filling forms, clicking buttons) on behalf of users using AI products like Project Mariner. Blocking Google-Agent has zero SEO impact.

Q: Does Google-Agent respect robots.txt?

Yes, Google-Agent respects robots.txt directives. You can control which parts of your site it can interact with.

Operated by Google (Project Mariner)

Quick Facts

User-Agent:Google-Agent

Category:Google Bots

Operator:Google

Safety:Safe

Blocking Impact:Low — No SEO ranking impact

SEO Impact Score:3/10

What is Google-Agent?

Google-Agent is Google's new user-triggered agentic crawler that navigates websites and performs actions (like filling forms, clicking buttons, and browsing pages) on behalf of users via products like Project Mariner. Unlike traditional crawlers that simply index content, Google-Agent is an agentic bot — it takes real actions on your site at the direction of a human user. It can fill out forms, navigate multi-step workflows, and interact with your site's UI elements. Each interaction creates a log event in your server logs, giving you data on how Google's AI agents engage with your website. Why this matters for WebMCP: If you see significant Google-Agent traffic in your logs, it's a direct data point showing that users are sending AI agents to interact with your site. This makes implementing WebMCP (Machine-Callable Protocols) a higher priority — you'll want structured endpoints that AI agents can use efficiently. Google-Agent uses IP ranges from user-triggered-agents.json and comes in both mobile and desktop variants: • Mobile: Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/W.X.Y.Z Mobile Safari/537.36 (compatible; Google-Agent; +https://developers.google.com/crawling/docs/crawlers-fetchers/google-agent) • Desktop: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Google-Agent; +https://developers.google.com/crawling/docs/crawlers-fetchers/google-agent) Chrome/W.X.Y.Z Safari/537.36

What happens if you block Google-Agent?

✅ **No SEO Impact** — Blocking Google-Agent does not affect your rankings in Google or any other search engine. Google-Agent is a user-triggered agentic bot, not a search indexer. However, blocking it means Google's AI agents (like Project Mariner) won't be able to complete tasks on your site when users request them. This could impact user experience for people using Google's AI assistant products. **Key consideration:** If Google-Agent shows high activity in your logs, it means users are actively sending AI agents to your site. Blocking it removes a channel of user engagement. Consider implementing WebMCP instead to give AI agents structured ways to interact with your site.

Safe to allow. Provides valuable data on AI agent interactions with your site.

How to block Google-Agent with robots.txt

<code>User-agent: Google-Agent</code> — This is a user-triggered fetcher. Unlike traditional crawlers, it acts on behalf of real users via products like Project Mariner. Blocking it won't affect SEO, but it may prevent Google's AI agents from completing user-requested tasks on your site.

Block completely (robots.txt)

User-agent: Google-Agent
Disallow: /

Allow all (robots.txt)

User-agent: Google-Agent
Allow: /

Block private only (robots.txt)

User-agent: Google-Agent
Disallow: /private/
Disallow: /api/
Disallow: /admin/
Disallow: /checkout/
Allow: /

Nginx server block

# Nginx: Block Google-Agent
if ($http_user_agent ~* "Google-Agent") {
    return 403 "Bot blocked";
}

Apache .htaccess

# Apache: Block Google-Agent
SetEnvIfNoCase User-Agent "Google-Agent" bad_bot
Order Allow,Deny
Allow from all
Deny from env=bad_bot

Meta robots tag

X-Robots-Tag header

X-Robots-Tag: noindex, nofollow

Is Google-Agent safe to allow?

Yes, Google-Agent is a **safe and legitimate** bot operated by Google. It is a user-triggered fetcher that only acts when a real user requests an AI agent to interact with your site (e.g., via Project Mariner). It is documented in Google's official crawlers page and uses verifiable IP ranges from user-triggered-agents.json. **Strategic value:** Allowing Google-Agent gives you real data on how AI agents are interacting with your site. If you see significant traffic, it's a strong signal that implementing WebMCP should be a priority. Use your AI crawler checker free tool to monitor its access.

Verify by checking IP against Google's user-triggered-agents.json IP range list.

What does Google-Agent do?

Google-Agent is fundamentally different from traditional crawlers. It's an agentic bot that takes actions on your site.

Navigates your site on behalf of users who request AI assistance (Project Mariner)
Fills out forms and completes multi-step workflows at user direction
Clicks buttons, follows links, and interacts with UI elements
Creates server log events that let you measure AI agent engagement
Uses IP ranges from user-triggered-agents.json for verification
Does NOT index content or affect search rankings
Provides data showing how important WebMCP implementation is for your site

Frequently Asked Questions

What is the official user-agent string for Google-Agent?

Google-Agent has two user-agent strings: Mobile:

Mozilla/5.0 (Linux; Android 6.0.1; Nexus 5X Build/MMB29P) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/W.X.Y.Z Mobile Safari/537.36 (compatible; Google-Agent; +https://developers.google.com/crawling/docs/crawlers-fetchers/google-agent)

Desktop:

Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; Google-Agent; +https://developers.google.com/crawling/docs/crawlers-fetchers/google-agent) Chrome/W.X.Y.Z Safari/537.36

The W.X.Y.Z is replaced with the actual Chrome version number.

Is Google-Agent safe?

Yes, Google-Agent is a **safe and legitimate** bot operated by Google. It only acts when triggered by a real user via products like Project Mariner. It's documented on Google's official crawlers page and uses verifiable IP ranges.

Will blocking Google-Agent hurt my SEO?

✅ **No SEO Impact** — Blocking Google-Agent does not affect your rankings in Google or any other search engine. It's a user-triggered agentic bot, not a search indexer. However, blocking it prevents Google AI agents from completing user-requested tasks on your site.

How do I block Google-Agent in robots.txt?

Add the following lines to your /robots.txt file:

User-agent: Google-Agent
Disallow: /

This instructs Google-Agent not to perform any agentic actions on your site. For partial blocking (e.g., protect checkout but allow browsing):

User-agent: Google-Agent
Disallow: /checkout/
Disallow: /account/
Allow: /

What is the difference between Google-Agent and Googlebot?

Googlebot is Google's search indexing crawler — it crawls pages to build Google's search index. Blocking it removes you from Google Search. Google-Agent is a user-triggered agentic bot — it navigates your site and takes actions (filling forms, clicking buttons) on behalf of users using AI products like Project Mariner. Blocking it has zero SEO impact but prevents AI-assisted user interactions.

What is Project Mariner?

Project Mariner is Google's AI agent product that uses Google-Agent to browse the web and perform tasks on behalf of users. When a user asks Project Mariner to do something on a website (like fill a form or find information), Google-Agent is the bot that actually visits and interacts with the site.

How does Google-Agent relate to WebMCP?

If Google-Agent has a large number of interactions with your site, it means users are sending AI agents to interact with your content. This is a direct data point showing you should implement WebMCP (Machine-Callable Protocols) — structured endpoints that let AI agents interact with your site more efficiently. Monitor Google-Agent traffic in your logs to prioritize WebMCP implementation.

How do I verify Google-Agent in my server logs?

Search your web server access logs for Google-Agent:

grep -i "Google-Agent" /var/log/nginx/access.log

You can verify legitimate requests by checking the source IP against Google's user-triggered-agents.json IP range list. Google-Agent interactions create distinct log events for each agentic action (form fill, navigation, etc.).

Does Google-Agent respect robots.txt?

Yes — Google-Agent respects robots.txt directives. You can control which parts of your site it can interact with using standard robots.txt rules with User-agent: Google-Agent.

How often does Google-Agent crawl my site?

Google-Agent is user-triggered, meaning it only visits your site when a real user asks Google's AI (like Project Mariner) to perform a task on your site. Traffic volume depends on how many users request AI agent interactions with your website. Monitor your server logs to track actual visit patterns.