Google has updated its list of fetchers triggered by Google users to reflect the Google Notebook name change. Users who hardcoded the old user agent for robots.txt or other reasons have a grace period of a few weeks before the old user agent stops working in August 2026.
Reasons to Block Gemini Notebook
Gemini Notebook’s Discover Sources feature will remove online articles without the site owner’s permission. This feature retrieves up to ten sources for the user-defined query or topic, provides an AI summary, and generates no referrals.
Gemini Notebook’s audio and video presentation allows you to reuse online content and turn it into an audio podcast or explainer video. This result, if used online, can then compete with the original source material.
All of these ways of using online content to generate other forms of content are intended functions of Gemini Notebook. It automates the process of scraping and creating something else from unique online content without attribution to the original source.
Site owners who want to block Gemini Notebook will need to update their firewalls and .htaccess files to continue working.
NotebookLM is now Gemini Notebook
NotebookLM has been renamed Gemini Notebook. Gemini Notebook is exactly the same. There is no change to how it works or what it does.
Gemini Notebook is a research assistant that allows users to upload documents that can serve as ground truth and enable better answers, research, and learning using the uploaded material. Gemini Notebook is multimodal, which means it can work with YouTube and download audio files.
Gemini Notebook’s multimodality also works the other way around. It can turn downloaded materials into an audio or video podcast episode, which can be useful for learning more about a topic.
Why the Gemini Notebook User Agent is Important
What is important for SEOs and website owners is that Gemini Notebook can scrape web pages and use them for user searches. This works either by user-pasting URLs or by using the Discover Sources feature, which can automate the process of finding articles and web pages to add as research sources.
The scrapers or robots used by Gemini Notebook are classified as user-initiated scrapers, and since they are initiated by users, they do not obey the robots.txt file.
However, a site owner can configure a firewall rule to block user-triggered grabbers or create an .htaccess rule to do the same.
Here is an example of how to do this:
RewriteEngine On
# Block Google-GeminiNotebook
RewriteCond %{HTTP_USER_AGENT} Google-GeminiNotebook (NC)
RewriteRule ^ - (F,L)
The Mariner project disappears completely
Project Mariner was retired in May 2026 and Google’s documentation was updated to reflect this.
THE old documentation it read like this:
“Google-Agent related products are used by agents hosted on Google infrastructure to browse the web and perform actions at the user’s request (e.g. Project Mariner). It uses IP ranges from user-triggered-agents.json. “”
The above section of the User Triggered Collector documentation is otherwise the same except for the removal of this part: (for example, Project Mariner).
Mention of NotebookLM removed
The other consequential change is the complete removal of Google NotebookLM from the documentation.
This is deleted:
“Google NotebookLM
User-Agent in Google-NotebookLM HTTP requests
Related Products The Google-NotebookLM retrieval tool requests individual URLs that NotebookLM users have provided as sources for their projects.
The deleted section has been replaced with new documentation that reflects the name change to Gemini Notebook.
This is the new documentation:
« Gemini notebook
User agent in Mobile Agent HTTP requests
Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/138.0.0.0 Mobile Safari/537.36 (compatible; Google-GeminiNotebook; +https://developers.google.com/crawling/docs/crawlers-fetchers/google-gemininotebook)
Office AgentMozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/137.0.0.0 Safari/537.36 (compatible; Google-GeminiNotebook; +https://developers.google.com/crawling/docs/crawlers-fetchers/google-gemininotebook)
Former agent (supported until August 2026) Google-NotebookLM
Related Products The Gemini Notebook Retrieval Tool requests individual URLs that Gemini Notebook users have provided as sources for their projects.
As mentioned earlier, the Google-NotebookLM user agent will continue to work until August 2026.
The changelog explains:
“If you have hardcoded the old value in your code, update the string to avoid potential bugs. We will continue to support the old value to allow for a smooth transition.”
Takeaways
Google’s name change from NotebookLM to Gemini Notebook comes with an update to its documentation. The new documentation removes the old user agent (Google-NotebookLM) and replaces it with documentation specific to the new user agent (Google-GeminiNotebook).
Site owners who use the legacy user agent to track or block Gemini Notebook crawler and scraper activity only have a few weeks to update their firewalls or .htaccess files.
User-triggered grabbers still don’t obey the robots.txt file. Robots.txt is not a directive. A directive is something that a robot must obey. So there is no need for the Gemini Notebook crawler to obey it. But site owners can still control access to content using a firewall or .htaccess file.
Featured image by Shutterstock/Drawlab19
