Google has renamed NotebookLM to Gemini Notebook, and the rename carries a technical change that can quietly break your defenses. The fetcher's user-agent string switched from "Google-NotebookLM" to "Google-GeminiNotebook." Search Engine Journal reported that the tool works the same as before, but any block rule you set against the old name stops matching. If you were blocking the crawler, you are not anymore, unless you update the rule.
What changed and why it matters
The name is new, the behavior is not. Gemini Notebook still pulls content the same way NotebookLM did. Its Discover Sources feature scrapes up to ten web articles per query, and its multimedia features turn that content into audio and video summaries. None of that sends referral traffic back to the sites it draws from. Your material can end up repackaged with no link and no visit in return.
There is a second detail that makes this harder to control. These are user-triggered fetchers, meaning a person asks for the content and Google goes and gets it. Fetchers of that kind do not obey robots.txt. So the usual robots.txt disallow does not stop them. The block that works is at the server or firewall level, matched on the user-agent string, and that string just changed.
The rename itself is cosmetic, but the effect on site owners is not. A block is only as good as the string it matches, and this one now matches a name that is on its way out. Sites that set up the rule months ago and moved on are the most exposed, because nothing in their dashboard will flag that the protection lapsed. The content keeps getting fetched, the summaries keep getting built, and the first sign of a problem is usually noticing your own material inside an AI answer that never sent a visitor.
The fix is a one-line update
If you previously blocked Google-NotebookLM in your firewall rules or .htaccess, add or switch the rule to Google-GeminiNotebook before August 2026. A rule that still names the old agent protects nothing once the rename completes. This is a small edit, but it only helps if someone actually makes it.
A quick checklist:
- Find any existing rule that references Google-NotebookLM in .htaccess, nginx config, or your WAF.
- Update the user-agent match to Google-GeminiNotebook, or add a new rule alongside the old one.
- Test that a request sending the new user-agent gets blocked.
- Do this before August 2026, when the change takes effect.
Should you block it at all?
That is a judgment call, not a rule. Blocking cuts off a channel that gives you no referral traffic and can repackage your work without attribution. Allowing it keeps your content eligible to appear inside those AI summaries, which some publishers want for visibility. The right answer depends on whether you value the exposure more than the lost visits. What you should not do is assume your old block still works, because that is the trap in this rename.
What this means for Thai marketers
Any Thai site owner who set up a block against Google-NotebookLM needs to revisit it. The protection you put in place is now pointing at a name that is going away, and it will stop working when the rename lands. Updating the rule to Google-GeminiNotebook restores whatever control you had.
This fits a bigger shift in how sites get read. Search and discovery increasingly run through AI systems that summarize rather than link, which is the whole reason AI SEO and generative engine optimization have become their own discipline. Deciding which crawlers to allow, and which to block, is part of that work now. For sites competing in local results, the same crawler decisions feed into SEO in Thailand, where being cited or ignored by AI tools shapes visibility.
FAQ
What is the new user-agent string?
Google-GeminiNotebook, replacing Google-NotebookLM. The tool's function is unchanged.
Will robots.txt block it?
No. As a user-triggered fetcher it does not obey robots.txt. Blocking has to happen at the firewall or server level on the user-agent.
By when do I need to update my rules?
Before August 2026, or an existing block against the old name will stop protecting your content.
If you are weighing which AI crawlers to allow and how it affects your visibility, Relevant Audience can help you set the policy and the technical rules to match. Reach out about your AI SEO and GEO strategy.
