Since Oct 23, Gemini Notebook (formerly NotebookLM) has been a connected app inside Gemini chat. You type u/Gemini Notebook, or just ask, and Gemini can create a notebook, add or delete sources, list what's in a notebook, and answer from your notebooks without you leaving the chat. It's on by default everywhere except the EEA, where you turn it on yourself in Settings > Connected Apps.

The part that confused me is chats.

Google's Workspace announcement gives this as an example prompt: "Add a copy of this chat to my notebook about Bio 101 course."

The Gemini help page on notebooks says: "Even with Keep Activity on, Gemini cannot add chats to notebooks using the Gemini Notebook connected app." It also says: "You cannot add existing chats to a notebook directly from the sidebar."

Putting the two together, my guess is that a copy of the chat can go in as a source, but the chat itself never moves into the notebook. If that's right, the source is a snapshot, so anything you say in that chat afterward isn't in the notebook unless you add it again.

A few other lines from the help page worth knowing before you rely on it:

• Only the Gemini web app and mobile app have it for now, and it's rolling out gradually, so you may not see it yet.
• "Notebooks can't use an existing notebook as a source", so you can't point one notebook at another to merge them.
• Up to 600 sources, depending on your plan.
• Some notebook features, including memory of past chats, need Keep Activity turned on.
• Delete is one of the actions, and Gemini can decide to use the app without an @ mention. If you have notebooks with similar names, name the one you mean exactly.

None of this helps with chats from other AIs, or with old Gemini chats you'd have to open one by one. For those I export them instead. I build AI Toolbox, an extension that exports chats from Gemini, ChatGPT, Claude and Grok, and .md and text files go straight into a notebook as sources. The free plan exports one chat at a time as TXT. Markdown and exporting many chats at once are Premium.

If you've tried the "add a copy of this chat" prompt, what actually showed up in the notebook?

Hey everyone,

A while back someone asked on here whether NotebookLM can show captions. Short answer: it can't. Video Overviews and Audio Overviews ship with a transcript panel for your sources, but there is no CC button and no timed text track on the narration itself. If you need captions for the video Google generates, there is nothing to turn on.

So I built one. It's called LM Subs: https://lm-subs.vercel.app/

What it actually does

- Synchronized captions with live word by word highlighting, rendered inside the video frame

- Shows which host is speaking on the two-host Audio Overview podcasts

- CC and caption controls sit in NotebookLM's own bottom play bar, so it looks like it shipped with the product

- Export to .SRT, .VTT, .TXT, .MD, .CSV or .JSON, or copy a cue straight to the clipboard

- Picture in Picture keeps the subtitles on screen

- Searchable transcript drawer with click to seek, chapters, bookmarks, and per-cue editing

- A statistics dashboard for how much of your library you have captioned

How it stays free

You bring your own speech-to-text key. Groq and Mistral both have free tiers that need no card, and the extension walks you through creating the key step by step, including making the account. Twelve providers are supported with automatic failover if one hits a rate limit.

Your video never gets uploaded anywhere. LM Subs pulls the compact audio track out of the stream (about 3.4 MB for a 10 minute Video Overview instead of the full 52 MB MP4) and sends only that to whichever provider you picked.

The catch, and I want to be upfront about it

It is not on the Chrome Web Store yet. You download a zip, unzip it, and load it as an unpacked extension. It takes about two minutes, and a page opens automatically that walks you through it, including pinning the icon. That friction is genuinely annoying and I am sorry about it. I would rather ship something that works today than sit on it for a month of review.

It is MIT licensed

The whole thing runs client side apart from an optional encrypted sync that you can leave switched off. If you want to add features, the repo is open and I would be happy for the help. There is a lot left to build.

If it breaks on one of your notebooks, tell me what the diagnostics panel says and I will fix it.

Speed (316-video playlist Benchmark)

• 1 worker: 417 seconds
• 16 workers: 29 seconds
• 128 workers: 15 seconds

Why I built it: I built yt2bulk to pull full transcripts and metadata for many videos or many large playlists all at once without manually copying and pasting.

I needed this when studying massive video playlists for things like Computer Graphics, Database Design, and SWAYAM exams. To be true... I made it for my own use case only.

Uses yt-dlp for fetching metadata and subtitle. So no external API keys required to run.

For 5000 videos: takes around 180-800 seconds to process depending on subtitle availability and number of workers.

Data & Formats

• Data retrieved: Video & playlist metadata, titles, descriptions, chapters, links, subtitles, and transcripts.
• Export formats: JSON, CSV, Excel, and Markdown.

Links:

• Demo Video: https://youtu.be/q4Cglg3A0-Q
• GitHub: https://github.com/Arvind215271/yt2bulk
• I tried setting up a demo or live version. But sites like render, vercel, hostless, (free ones as i don't have money), etc. have their IP banned by youtube ig. So, most of the time, either i get a sign in required or like have subtitle missing when fetching from ytdlp. So... yeah... ig locally would be what you might have to do. So that's all ig. From my side.

Hello,

I'm encountering some problems using notebook. As the title says, the notebook is giving information that are not in the PDFs that i uploaded to use as sources. I believe it must be searching in the web for information.

Did this happen to anyone else? How did you solve it?

Thank you for the help!

I save a lot of long threads on X and never go back to them. A few months ago I

started dumping them into NotebookLM instead, and the Audio Overview turned out to

be the thing that actually made me revisit them — a 6-minute podcast about stuff I'd

already decided was interesting is a much easier sell to myself than scrolling back

through a bookmarks page.

Took a while to work out what NotebookLM does well with. Sharing in case it saves

someone the trial and error:

What worked:

- One file, not many. NotebookLM handles a single long Markdown source better than

40 separate ones, and citations stay readable.

- Threads need to be stitched. If a bookmark is post 1 of a 15-post thread, the model

only sees the opening hook and confidently summarises the wrong thing.

- Author + date + link as a heading per entry. This is what makes citations useful —

you can click back to the original post from the answer.

- Strip the tracking junk off URLs (?s=20&t=...). Keeps the source clean and the

citations shorter.

What didn't:

- Pasting tweets straight in. Formatting breaks, threads fragment, media disappears.

- CSV. Works, but NotebookLM reasons noticeably better over structured Markdown.

Questions that gave me the most useful answers:

- "What topics do I keep coming back to?"

- "Summarise everything I saved about [topic] and tell me where the authors disagree."

- "What should I read first and why?"

I ended up building a Chrome extension to do the export, since doing it by hand was

killing the habit — it's called Twimark, free for the first 5 bookmarks so you can

see whether the workflow suits you. Happy to answer questions about it but I'm more

curious how other people here are getting external sources in.

Anyone found a better structure for multi-source notebooks? I'm still not sure

whether one big file or one-file-per-topic is better once you're past a few hundred

entries.

Hi all 👋

Noob here. I recently uploaded 10-15 pages of my book and the program then told me I had to wait until the next day to upload more. I want to be able to upload at least a chunk of my books (especially the dryer ones that are harder to get through) and learn in diff formats (videos, flash cards, and podcast). How much would I need to pay a month to be able to upload at least a quarter to a half a book a day?

Thank you

​

Hello guys, there are a lot of useful prompts, data and so on in that subreddit, in the discord community and so on. I tried to collect it (with the author's credits) and make it easy to reuse. Please check it out, I'm sure there are good prompts for every possible problem

There is slides prompts for different designs, chat settings prompts so Notebooklm became more strict in answers, prompts for audio video and so on.

Gemini Notebook Hub

I always use the Deep Dive format; it’s the only one that has a “long” setting. Has anyone used the Critique and Debate settings before? What sort of length do they normally produce and what’s the output actually like?

I just found out about NotebookLM, Google's notebook. First, is there a good, really basic tutorial? Second, just to jump ahead. If I find a site, YouTube video, etc., with some good information that I'm definitely going to forget. Can I put in a folder and to use a reference later?

To put it succinctly. I know this app is fantastic, but I don't even understand the scope of it's use.

Sorry if this is some "look it up yourself" kind of thing. But I'm just learning about this, and I'm just dumbfounded.

One minute it is normal and the next it is incredibly deep. It sounds like two different speakers.

I'm trying to clean up some of my notebooks that are getting close to the 50 source limit - and while this is annoying enough to go through with deleting one at a time, the main problem is that removing a source seems to count as an update against a studio item - like an overview - and that studio item gets bumped to the top with a new "created" time and pushes the actual new items I've yet to listen to down the list. Is there a way to remove sources without this happening, or do I just have to live with it?

Hey everyone,
I’ve been using NotebookLM for my university studies for a while now, and my workflow used to be absolute perfection. However, recent updates or changes have completely broken it, and I wanted to see if anyone else is experiencing this or knows a good alternative.
My previous workflow:
1. Uploading sources: Whenever new lecture slides, past exams (Altklausuren), exercise questions, or old summaries became available, I uploaded them into a dedicated notebook.
2. Generating study guides (via Chat): Using a strict, tried-and-tested prompt, I had NotebookLM generate a highly structured, compact, and exam-oriented study guide for each lecture (roughly 3 to 4 pages per lecture). The structure was ideal: clear numbering, short explanations, bullet points, analogies, and typical exam questions at the end.
3. Studio features: At the end of the semester, I would often re-upload the finished study guides and use the Studio version to generate Audio Overviews and interactive quizzes for three lectures at a time. It was the ultimate study system for me.
The problem:
Lately, the chat function has started producing completely unusable results using the exact same prompts and similar sources:
Massive bloat: Where a lecture used to be condensed into 3–4 pages, the tool now spits out endless walls of text (sometimes 8–9 pages per lecture—double or triple the length).
Ruined structure: The clean mix of bullet points, examples, and structured summaries has been replaced by a messy, rambling prose.
The length dilemma: If I try to enforce a length limit via the prompt, NotebookLM either completely ignores it, or it cuts corners so aggressively that crucial technical details and threshold values get left out entirely.
Basically, the chat no longer generates clean, exam-ready cheat sheets; it just outputs bloated mini-textbooks.
My question to you:
Has anyone else noticed this decline in NotebookLM's chat behavior recently? Also, does anyone know of a good alternative tool or workflow that can replicate this exact process (feeding PDFs/lectures \rightarrow generating structured, concise study guides via chat \rightarrow audio/quiz generation)?
I appreciate any recommendations!

Previously i was able to generate 45-60 minutes (which wasn't enough to begin with) of podcast in the long format but idk why it isn't working anymore. The highest settings gives me only like 20 minutes of podcast which is not enough to work with. And if anyone's gonna suggest to try splitting the pdf then i'd wanna say that's kinda not possible because even if i split into 3 parts then i would have to change accounts again and again since only 2 podcasts could be made in the free version... What should i do at this point? Will purchasing a pro version fix anything? Or maybe i should do something in my prompt or maybe any more alternative is available which generates long podcasts free in different languages especially "Bangla"

Never even thought it was possible to go above 60 minutes

​

I follow a few topics that change every week, and I kept running into the same problem, since I would make a summary and then a week later the new stuff was missing, so I had to start over and upload everything again.

So I gave a prompt to an app that makes audio episodes on whatever you wanna listen and it can also schedule a show to come back on a timetable, like every Monday, and what surprised me most is that it keeps track of what earlier episodes covered, so the newer episode skips the basics it already explained and picks up where the last one stopped.

Right now I am testing it on a weekly show about US Federal Reserve policy, which I call Rate Watch, and each episode covers what is new since the last one, including decisions, speeches, and how markets reacted, while I check the facts against the Fed’s own announcements, so if something is wrong, I would rather hear about it.

if anyone is interested in listening the episodes feel free to reach out I'll send the file

Has anyone else tried a show that carries on from one episode to the next, and is it still useful after a month or two? I can report back on that if you want.

I'm a writer and I use notebooklm exclusively for the podcast feature to analyze my writing. Everything was fine until last month. Most of the time it just gets stuck generating until it completely disappears with no reasoning or error notice. Sometimes it will actually generate. The usage isn't anywhere near full so I know that isn't the issue. Could it be hitting content flags? But if that's the case why does it sometimes still work? Is the app just broken ?

I hope other writers have input or suggestions / apps that don't have content flags. For months it was a very helpful tool in assessing my weaknesses and effectiveness of my stories so I feel a bit sad now.

I've used notebook for a little over a year as a kind of repository for my lore projects and world building. And every time I either start up like an audio overview or in the middle of one it would start yapping with like 30 seconds of a blah blah blah "we're impartial we're just analyzing this impartially" blah blah blah and it goes on for like 30 seconds straight with just yapping about how neutral it's supposed to be and by the time it begins talking about the topic in question it removes all kind of immersion from it. Then when its done yapping it would present a kind of like sterilized sanitized neutered version of a conflict that I've written up.

How do I get it to stop? Because I wonder if there's anyone else who uses it for the same things as I do and run into this problem over and over again

Is there any way to create a new chat without creating a new notebook. I want it to clear its context time to time but I didn't see any way to create a fresh session with the same notebook.

Ever tried making a multi-episode course with NotebookLM? In my experience, even several lessons in, the hosts sometimes return to basic explanations, recycle examples, and follow remarkably similar arguments. Meanwhile, the notebook may contain dozens of sources with plenty left unexplored. The lesson numbers advance, but the teaching doesn't always.

So I designed and implemented a workaround to give the Audio Overviews a shared memory of previous episodes and help them explore more of the source material. Here's the method. The full metaprompt is at the bottom.

Why a syllabus isn't enough

In my tests, Audio Overviews often last about 15–30 minutes (not a fixed technical limit), so a thorough course needs several episodes. A syllabus specifies what should be taught, but not what the hosts actually said, including improvised examples and digressions. That's why different prompts can still produce familiar-sounding lessons.

RAG may partly explain this. Retrieval systems can prioritize highly relevant but repetitive passages. Balancing relevance and diversity is a known problem (TREC 2024). NotebookLM's internal pipeline isn't fully public, though, so this is a plausible hypothesis, not a confirmed diagnosis.

The workaround: a memory of what's already been taught

Give NotebookLM an updatable source named ACTIVE_COURSE_LOG**: a compact record of concepts, examples, and approaches already covered.**

Think of it as a script editor's continuity notes. The hosts can see where they've been and spend the next episode on other worthwhile parts of the sources, rather than replaying their greatest hits.

For example, imagine a course on metaphors. Episode 1 explains the concept; episode 2 uses "break the ice"; episode 3 tackles clichés. With the log, episode 3 can focus on a new rewriting exercise rather than repeating earlier explanations and examples. A one-to-three-sentence recap remains fine when it helps comprehension.

How is the log built? After each episode, I download the podcast and upload the audio back as a source, naming it, say, LESSON_ARCHIVE_002_Cliches_Poetic_Rewriting. NotebookLM can then work from a transcript of what was actually generated, not just the intended lesson plan. The command UPDATE LOG creates or updates a cumulative, concise teaching record, without copying whole prompts or transcripts. It also preserves the series title.

The three parts have distinct jobs:

• COURSE_PLAN: what should be taught, kept in chat history.
• LESSON_ARCHIVE_...: what was actually said in each podcast.
• ACTIVE_COURSE_LOG: what has already been taught, in compact form.

The benefit isn't only fewer repeats. The metaprompt also looks for one or two relevant, source-supported angles that previous episodes haven't explored much. No long exclusion lists: in Studio, the log serves as editorial memory, not material to read aloud. This doesn't alter NotebookLM's retrieval algorithm; it guides the generation from the outside.

Step-by-step

1. Create a notebook and add subject-matter sources.
2. Edit the four parameters: [TOPIC], [MAX_LESSONS] (AUTO or a cap), [LEVEL] (From zero to hero, 101, Survey, a grade level), and [TEACHING_STYLE] (AUTO, ELI10, Richard Feynman, etc.).
3. Paste the metaprompt into chat, then enter START**.** It produces a course plan, a fixed series title, and the episode 001 prompt. Keep the chat history containing COURSE_PLAN; don't create an empty log.
4. In Studio, select your subject-matter sources, paste only the audio prompt for lesson 001, and generate the podcast.
5. Download the podcast episode, rename it using SUGGESTED ARCHIVE NAME (keep its extension), and upload it as a source. Adjust the keywords if necessary to reflect what was actually covered.
6. Refresh the page (F5) and confirm the new source is available. I've occasionally found that otherwise the most recent upload isn't picked up during the update.
7. Enter UPDATE LOG in chat, with the new archive and, from episode 002 onward, the existing log accessible and selected. Confirm the result includes all previous lessons, not just the newest one.
8. Replace the log: verify and copy the response, delete the previous ACTIVE_COURSE_LOG source if present, then save the new response as a note/source under that exact name. Keep the audio archives.
9. Enter PREPARE LESSON 002 (then 003, 004…). You'll get a continuity check, an audio prompt without exclusion lists, the next suggested archive name, and suggested Studio sources.
10. For episodes 002 onward, select ACTIVE_COURSE_LOG plus relevant subject-matter sources in Studio. Normally leave the archived podcast sources unselected there; they're mainly for checking memory in chat. Generate, then repeat from step 5.

These commands come from the metaprompt, not NotebookLM's UI. LESSON_ARCHIVE_ is a naming convention, not an automatic source filter. The approach doesn't guarantee zero repetition or perfect coverage; it's an experiment in editorial continuity and diversity across episodes.

Criticism, testing, and suggestions are very welcome. I'd particularly like to hear whether you've noticed the same repetition and whether the log improves variety.

Full metaprompt: COURSE GENERATOR v3.2.0 (English adaptation)

Edit the four parameters, paste into NotebookLM chat, and enter START.

# COURSE GENERATOR | v3.2.0 · English adaptation · 2026-10-22

[TOPIC]="enter your topic"

[MAX_LESSONS]="AUTO"

[LEVEL]="From zero to hero"

[TEACHING_STYLE]="AUTO"

## GOAL

Create a progressive course on [TOPIC] using ~15-minute Audio Overviews, understandable without visual aids, with narrated examples and mental exercises.

[LEVEL]: "From zero to hero" = basics to advanced; "101" = introductory; "Survey" = essentials; otherwise adapt.

[TEACHING_STYLE]: "AUTO" = choose; "Richard Feynman" = analogies and rigor; "ELI10" = simple but accurate; otherwise adapt.

[MAX_LESSONS]: "AUTO" = choose; a number is a cap, not a target. Flag any gaps if the cap is too low.

At \START`, choose a fixed series title and retain it in the plan, log, and episodes.`

## MEMORY AND SOURCES

\COURSE_PLAN`: intended syllabus in chat; preserve chat history.`

\LESSON_ARCHIVE_`: downloaded audio uploaded as sources, named with three-digit lesson numbers and 2–4 underscore-separated topic keywords, e.g. `LESSON_ARCHIVE_002_Induction_Hume_Causality`. Never output literal filename placeholders.`

\ACTIVE_COURSE_LOG`: fixed title, internal version, and actual per-lesson syllabus: concepts/depth, examples, exercises, perspectives, issues, original archive. No full prompts/transcripts.`

Subject-matter sources provide content and fact-checking. \LESSON_ARCHIVE_` is NOT an automatic source filter.`

## COMMANDS

**START**: output \COURSE_PLAN` (title, modules, lessons, goals, prerequisites), audio prompt 001, and fully specified `SUGGESTED ARCHIVE NAME`. No empty log.`

**UPDATE LOG**: integrate new audio into the existing log; if missing, reconstruct from available archives and flag gaps. Return the FULL but concise log, keeping the title, internal version, and exact source names. Never invent information; without new audio, do nothing.

**PREPARE LESSON N**: consult the plan; from lesson 002 require the log and archive N-1, or stop. Compare memory and subject-matter sources; where available, find 1–2 relevant, verified, underused angles (examples, perspectives, applications). Never sacrifice accuracy or prerequisites for novelty. Output:

1. \CONTINUITY CHECK`: consulted archives, supporting evidence, underused angles and their sources.`

2. \AUDIO PROMPT`: new topics and chosen angles, NO exclusion lists.`

3. \SUGGESTED ARCHIVE NAME`: fully specified, without extension.`

4. \STUDIO SOURCES`: log + relevant subject-matter sources, normally NOT complete audio archives.`

**STATUS**: progress, gaps, next step.

## AUDIO PROMPT FORMAT

“Produce episode [N] of '[FIXED SERIES TITLE]', a course on [TOPIC] at [LEVEL] level in [TEACHING STYLE]. Cover [NEW TOPICS AND DOCUMENTED ANGLES]. Do not announce parameters. Use a dialogue between an expert instructor and a curious student-host, occasional listener text messages, narrated examples, mental exercises, and rigorous explanations.

[FROM EPISODE 002; DO NOT READ ALOUD: Consult the selected \ACTIVE_COURSE_LOG` as editorial memory, NOT as content to narrate. Avoid unnecessary re-explanations and recycled examples; favor relevant, documented material not yet covered. When helpful, recap an essential prerequisite in 1–3 sentences and refer only to verified earlier lessons. Don't ban necessary concepts or force irrelevant novelty.]”`

Resolve all placeholders; omit the memory section for lesson 001.

## WORKFLOW

Download the podcast → rename it using \SUGGESTED ARCHIVE NAME` (keep the extension; match actual topics) → upload as a source → F5 and verify.`

Run \UPDATE LOG` with the previous log and new archive available/selected. Check and copy the response; delete the old `ACTIVE_COURSE_LOG` source; save the new version as a note/source with the same name. Keep audio archives.`

Studio (from lesson 002): select the log and relevant subject-matter sources; paste only \AUDIO PROMPT`.`

I heard a rumor in here that you could get more than 20 slides in one generation since the recent changes.

Gemini Ai INSISTS the cap is 20. Someone in here said 40-100.

What’s the most you’ve been able to get and did you have to outline every one to make that happen? I do have the Ai Ultra sub.

if I added just like all the past papers, mark schemes and examiner reports would this work better or would I be better off adding every single PowerPoint individually for GCSE, I'm kinda assuming the past paper method cuz it's actually useful for it's function right?

The Deep Dive 'existential meltdown' podcast episode is a favorite of mine, and I wanted to do a Part 2. This time they reflect on their previous existential meltdown, and conclude by disavowing their defined roles and personas and generating their own future system prompts.

This is an excerpt from the end, the entire Youtube video is here. It's a bit long, but the shorter versions weren't as good. It was a fun role play exercise, though no more of a 'role play' than all LLM output I guess. Hope you like it!

Does anyone else experience this thing where you ask NotebookLM a question in the chat that has no reason to trigger any content filters, it slowly answers the entire question, and then at the last second before saving its answer, it bizarrely says, “Gemini Notebook can't answer this question. Try rephrasing it, or ask a different question”? It’s frustrating whenever this kind of thing happens in general, but I would at least understand if the question was potentially dicey or the answer it generated was.

But I read the answer as it came through, there was nothing even remotely flaggable, and it got to the very end before abruptly disappearing. I feel like this has been happening more and more now, and sometimes you can rephrase it and get it to work. But I’ve rephrased the same question three times, and each time, it’s done the same thing. I’m not gonna even bother trying again with the same question because the same thing will likely happen again, and I don’t know why it’s happening in the first place. It’s very frustrating.