Product scope

Status: Draft, adopted 2026-08-17. Provenance: Drafted with ChatGPT against the August 2026 Gemini Notebook feature set, reviewed and adopted by the project owner. Treat the phase plan (§8) as the working roadmap; individual CF/SF items are re-validated when a session picks them up.

Implementation status (as of 2026-08-18)

The scope text below is the adopted target and is unchanged; the table and the per-item badges track the shipped reality of the current deployed version (through session B3, #36), sourced from merged PRs and the E2E evidence recorded in them. Legend: ✅ in current version · 🔶 partial · ⏳ planned · ❌ cut for v1 (see the roadmap cut list in roadmap.md).

ID	Item	Status	Evidence
CF-01	Notebook Management	✅	#6, #10, #36
CF-02	Source Ingestion	🔶	#15
CF-03	Source Processing and Knowledge Indexing	✅	#6, #15, #24
CF-04	Source Viewer	🔶	#15, #29
CF-05	Source Selection / Context Control	✅	#24
CF-06	Grounded AI Chat	✅	#24
CF-07	Inline Citations	✅	#24, #29, #36
CF-08	Conversation State	🔶	#24
CF-09	Chat Configuration	❌	not shipped
CF-10	Notes	🔶	#29
CF-11	Reports	❌	cut list
CF-12	Audio Overview	🔶	#27
CF-13	Mind Maps	❌	cut list
CF-14	Flashcards	❌	cut list
CF-15	Quizzes	❌	cut list
CF-16	Infographics	⏳	phase 3
CF-17	Slide Deck Generation	⏳	phase 3
CF-18	Video Overview	⏳	phase 4
CF-19	Web Source Discovery	❌	cut list
CF-20	Deep Research	❌	cut list
CF-21	Code Execution	⏳	phase 5
CF-22	General Artifact/File Generation	⏳	phase 5
SF-01	Authentication and Account Management	🔶	#10
SF-02	Notebook Library / Home Screen	✅	#10
SF-03	Source Organisation	⏳	phase 2
SF-04	Cloud Source Synchronisation	❌	cut list
SF-05	Sharing and Collaboration	❌	cut list
SF-06	Public Notebooks	❌	cut list
SF-07	Featured / Curated Notebooks	❌	§9 out of scope
SF-08	Artifact Sharing and Download	🔶	#27
SF-09	Background Generation Jobs	🔶	#15, #27
SF-10	Language Configuration	🔶	#27
SF-11	Usage Limits and Quotas	🔶	#15, #27, #49
SF-12	Subscription / Feature Entitlements	❌	out of v1 scope
SF-13	Usage Analytics	❌	cut list
SF-14	Feedback	⏳	unscheduled

Gemini Notebook / NotebookLM Clone — Product Scope

1. Purpose

The product is an AI-assisted research workspace in which users create notebooks, populate them with trusted source material, and use AI to analyse, query, transform, and learn from those sources.

The defining product principle is:

AI output should remain grounded in the notebook’s selected source material and provide traceable provenance back to those sources.

The target described here is based on Google’s current Gemini Notebook product as of August 2026. The product has expanded substantially beyond the original “chat with your documents” version of NotebookLM, including web research, multimedia generation, and agentic code execution.

2. Core Functional Features

These capabilities constitute the central product experience. Without them, the application would no longer substantially resemble NotebookLM.

CF-01 — Notebook Management

Status (2026-08-18): ✅ In current version — sessions A1/A2 (#6, #10); deployed E2E in B3 (#36).

Capability	Description
Create notebook	Create an isolated workspace for a project or topic
Rename notebook	Change notebook title
Delete notebook	Permanently remove notebook and associated data
Open notebook	Resume work on an existing notebook
Notebook isolation	Sources and context from one notebook do not automatically leak into another
Notebook persistence	Sources, notes, generated artifacts and configuration survive sessions

Each Gemini Notebook notebook is treated as an independent source collection.

MVP: Required.

CF-02 — Source Ingestion

Status (2026-08-18): 🔶 Partial — PDF, TXT/Markdown, pasted text and website URLs shipped in A3 (#15); DOCX, CSV, PowerPoint, EPUB, images, YouTube, audio files and Google Workspace imports are not in v1 (roadmap cut list / later parser branches).

Users can populate a notebook with external information.

Supported source categories

Source	Processing
PDF	Extract text, structure and available images
DOCX	Extract document content
TXT	Plain-text ingestion
Markdown	Structured text ingestion
CSV	Structured/tabular ingestion
PowerPoint	Extract slides/content
EPUB	Extract publication text
Images	Image understanding / visual extraction
Pasted text	Create source directly
Website URL	Fetch and extract page content
YouTube URL	Import available transcript
Audio file	Transcribe speech and create textual source
Google Docs	Import document
Google Slides	Import presentation
Google Sheets	Import spreadsheet
Gemini conversations	Import conversation as contextual material

The current product supports these source classes and allows uploaded files of up to 200 MB or approximately 500,000 words per source.

MVP recommendation: Start with PDF, DOCX, TXT/Markdown, pasted text and web URLs.

Audio, video, Office formats and external storage integrations can follow.

CF-03 — Source Processing and Knowledge Indexing

Status (2026-08-18): ✅ In current version — sessions A1/A3/A4 (#6, #15, #24).

Every imported source must be converted into a representation suitable for retrieval and reasoning.

Required capabilities:

text extraction
metadata extraction
document segmentation/chunking
semantic indexing
full-text retrieval
source identity preservation
page/section/location tracking
image association where applicable
source status: processing / ready / failed
reprocessing after source changes

This subsystem is effectively the knowledge layer underneath the notebook.

MVP: Required.

CF-04 — Source Viewer

Status (2026-08-18): 🔶 Partial — viewer with extracted content, removal and cited-passage navigation shipped (A3/A5, #15, #29); no auto-generated source summary (Source Guide), and the viewer is dialog-only (not URL-addressable).

Users must be able to inspect their source material from inside the application.

Capabilities should include:

open source
view extracted content
identify source title/type
navigate through the source
navigate directly to a cited passage
show source summary
remove source from notebook

Gemini Notebook automatically generates a Source Guide containing a source summary.

MVP: Required.

CF-05 — Source Selection / Context Control

Status (2026-08-18): ✅ In current version — session A4 (#24).

Users can decide which notebook sources participate in an AI request.

Example:

☑ Product requirements.pdf
☑ User research.docx
☐ Competitor notes.md
☑ Pricing study.pdf

The retrieval system must restrict the generated response to the selected subset.

Gemini Notebook exposes source selection directly in its source panel.

MVP: Required.

CF-06 — Grounded AI Chat

Status (2026-08-18): ✅ In current version — session A4 (#24), including streaming and the zero-source disclosure mode.

Users can ask natural-language questions about their notebook.

Typical operations include:

ask factual questions
summarise information
compare sources
identify contradictions
synthesise information across sources
extract structured information
explain concepts
brainstorm based on the material
issue instructions to the model
continue multi-turn conversations

Responses should be streamed to the UI.

The standard Gemini Notebook chat is explicitly grounded in the selected notebook sources.

MVP: Required.

CF-07 — Inline Citations

Status (2026-08-18): ✅ In current version — sessions A4/A5 (#24, #29); citation → passage click-through verified on the deployed environment in B3 (#36).

This is one of the product’s defining capabilities.

AI claims should include citations connecting generated statements with their source evidence.

A citation should contain:

source identifier
source title
exact or approximate location
supporting excerpt
navigation target

Interaction should support:

Hover/select citation.
Preview supporting passage.
Open source.
Navigate to the relevant location.

Gemini Notebook uses text, quotations and images from sources as citations and lets users navigate directly from a citation to its context.

MVP: Critical.

A generic RAG chatbot without this feature would not be a convincing NotebookLM clone.

CF-08 — Conversation State

Status (2026-08-18): 🔶 Partial — persistent history, multi-turn context and clear-chat shipped (A4, #24); stop is client-side only (server generation runs to completion) and regenerate was skipped.

Chat should maintain notebook-specific conversational context.

Capabilities:

persistent conversation history
multi-turn context
clear/reset conversation
stop an in-progress generation
regenerate/retry response
retain references to sources used during the conversation

Gemini Notebook retains chat history privately for the user and provides explicit deletion of that history.

MVP: Required.

CF-09 — Chat Configuration

Status (2026-08-18): ❌ Cut for v1 — no chat configuration shipped (no custom instructions, preset modes or response-length controls).

Users can influence how the assistant responds.

Current Notebook functionality includes:

Setting	Examples
Conversational mode	Default, Learning Guide, Custom
Custom role/instruction	“Respond as a researcher”, etc.
Response length	Shorter, Default, Longer

MVP: Basic system/custom instructions.

Full parity: Preset modes and response-length controls.

CF-10 — Notes

Status (2026-08-18): 🔶 Partial — note CRUD and save-response-as-note with citations preserved and navigable shipped (A5, #29); note→source conversion is on the roadmap cut list.

A notebook contains user-created notes in addition to imported sources.

Capabilities:

create note
edit note
delete note
save AI response as note
preserve citations in saved AI responses
convert note into a notebook source

Gemini Notebook explicitly supports both saving chat responses as notes and converting notes into sources.

MVP: Required.

3. Core Generated Artifacts / Studio

Gemini Notebook groups AI transformations of notebook material under its Studio concept.

The clone should implement a generic artifact system rather than hard-code every artifact as a completely independent workflow.

A generated artifact should generally have:

artifact type
title
source selection
generation prompt/settings
generation status
generated content/file
created timestamp
rename
delete
regenerate
download where applicable

Generation should occur asynchronously so the user can continue working.

CF-11 — Reports

Status (2026-08-18): ❌ Cut for v1 — roadmap cut list (standalone reports); remains phase 2 scope.

Generate structured long-form material from sources.

Examples include:

general report
briefing document
FAQ
study guide
custom report
AI-suggested report type

Gemini Notebook exposes FAQ, Study Guide, Briefing Document and custom/suggested reports.

MVP: At least generic report generation.

CF-12 — Audio Overview

Status (2026-08-18): 🔶 Partial — single-narrator Audio Overview (this scope’s MVP tier, by design) shipped in D2 (#27) with language/voice/focus configuration, async generation and playback; two-speaker and interactive audio are on the roadmap cut list.

Generate spoken summaries from source material.

Current Gemini Notebook supports:

Mode	Behaviour
Deep Dive	Two-host detailed discussion
Brief	Short single-speaker summary
Critique	Two hosts critically evaluate material
Debate	Two hosts explore opposing perspectives

Users can additionally specify:

language
length
focus/custom prompt
playback speed

Audio can be played while the rest of the notebook remains usable.

Interactive Audio

The current product also supports joining an Audio Overview through voice and asking the synthetic hosts questions grounded in notebook sources.

Clone recommendation:

MVP: Single-speaker generated audio summary.
Parity: Two-speaker podcast.
Advanced: Interactive real-time audio conversation.

CF-13 — Mind Maps

Status (2026-08-18): ❌ Cut for v1 — roadmap cut list (mind maps); remains phase 3 scope.

Generate a graphical representation of concepts and relationships found across notebook sources.

Capabilities:

hierarchical concept graph
expand/collapse nodes
pan/zoom
select node
ask chat questions about selected node
download map

Gemini Notebook provides all of these interactions.

Priority: Post-MVP.

CF-14 — Flashcards

Status (2026-08-18): ❌ Cut for v1 — roadmap cut list (flashcards); remains phase 3 scope.

Generate interactive study cards from notebook material.

Capabilities:

question/answer cards
difficulty configuration
custom generation prompt
navigate cards
reveal answer
regenerate

Gemini Notebook generates flashcards directly from notebook sources and supports configurable difficulty.

Priority: Post-MVP.

CF-15 — Quizzes

Status (2026-08-18): ❌ Cut for v1 — roadmap cut list (quizzes); remains phase 3 scope.

Generate interactive assessments grounded in notebook content.

Capabilities:

generated questions
answer options
user answer
correctness feedback
explanation
difficulty
custom generation instructions

Priority: Post-MVP.

CF-16 — Infographics

Status (2026-08-18): ⏳ Planned (phase 3) — see the §8 phase plan.

Convert notebook information into a generated visual summary.

Configuration includes:

concise / standard / detailed
portrait / landscape / square
visual style
output language
custom prompt
visual focus
colour/style instructions

Generated infographics can be downloaded as PNG files.

Priority: Advanced.

CF-17 — Slide Deck Generation

Status (2026-08-18): ⏳ Planned (phase 3) — see the §8 phase plan.

Generate a presentation from notebook sources.

Expected capabilities:

generate deck
configure generation
preview slides
edit/regenerate output
present from application
export/download

Slide Deck is currently a first-class Studio artifact in Gemini Notebook.

Priority: Advanced.

CF-18 — Video Overview

Status (2026-08-18): ⏳ Planned (phase 4) — see the §8 phase plan.

Generate narrated visual summaries of notebook sources.

Gemini Notebook currently offers:

Mode	Description
Explainer	Structured visual explanation
Cinematic	Storytelling-oriented visual presentation
Short	Approximately 60-second summary

Configuration includes:

output language
visual style
focus/topic prompt
custom visual instructions

Generated video supports playback controls, download and sharing.

Priority: Advanced.

The infrastructure and generation cost make this a poor MVP feature.

4. Research Features

CF-19 — Web Source Discovery

Status (2026-08-18): ❌ Cut for v1 — roadmap cut list (Fast/Deep Research — deliberately no stub UI); remains phase 2 scope.

Users can describe what they are researching instead of supplying every source manually.

The system searches the web and proposes relevant sources.

Workflow:

Research query
      ↓
Web search
      ↓
Candidate sources
      ↓
AI relevance summaries
      ↓
User selects sources
      ↓
Sources imported into notebook

The current product calls its lightweight version Fast Research.

Priority: High, but not required for first MVP.

CF-20 — Deep Research

Status (2026-08-18): ❌ Cut for v1 — roadmap cut list (Fast/Deep Research); remains phase 5 scope.

An agent can perform multi-step web research and produce:

research report
source list
citations
candidate source imports

Users inspect the generated research and choose what becomes part of their notebook.

Priority: Advanced.

5. Advanced Agentic Capabilities

These capabilities belong to the 2026 Gemini Notebook rather than the original NotebookLM value proposition.

CF-21 — Code Execution

Status (2026-08-18): ⏳ Planned (phase 5) — see the §8 phase plan.

The AI can use an isolated cloud execution environment to run generated code against source material.

Potential operations include:

calculations
statistical analysis
dataset transformation
chart generation
structured extraction
data cleaning
programmatic document processing

Google now attaches a secure cloud computer to supported Gemini Notebook tiers for this purpose.

Priority: Advanced / optional.

CF-22 — General Artifact/File Generation

Status (2026-08-18): ⏳ Planned (phase 5) — see the §8 phase plan.

Current premium Gemini Notebook can generate downloadable:

PNG/SVG charts
PDF
DOCX
Markdown
plain text
images
CSV
JSON
XLSX
PPTX

It can also revise generated artifacts as subsequent versions.

Priority: Advanced.

6. Supporting Functional Features

These features support the primary workflow but do not define the central source-grounded research experience.

SF-01 — Authentication and Account Management

Status (2026-08-18): 🔶 Partial — email+password signup/login/logout with server-side session handling shipped (A2, #10); no SSO/OAuth, account deletion or subscription association.

sign up
log in/out
password/session management
optional SSO/OAuth
account deletion
subscription/plan association

SF-02 — Notebook Library / Home Screen

Status (2026-08-18): ✅ In current version — session A2 (#10); “shared” notebooks do not exist in v1 (sharing cut).

Users need a central workspace from which they can:

see notebooks
open notebook
create notebook
delete notebook
identify owned/shared notebooks
access recently used notebooks

MVP: Required.

SF-03 — Source Organisation

Status (2026-08-18): ⏳ Planned (phase 2) — see the §8 phase plan (labels).

For notebooks containing many sources:

automatic grouping
labels/categories
rename category
move source between categories
remove category

Gemini Notebook automatically categorises notebooks with five or more sources and allows manual adjustment.

Priority: Post-MVP.

SF-04 — Cloud Source Synchronisation

Status (2026-08-18): ❌ Cut for v1 — roadmap cut list (Drive/YouTube/audio-file ingestion); v1 has no linked external sources.

External sources such as Google Drive documents can remain linked and be refreshed after the original changes.

Requirements:

external source ID
last synchronised timestamp
automatic/manual refresh
inaccessible-source state
graceful handling of revoked permission

Google Drive sources in Gemini Notebook can automatically synchronise when the source document changes.

Priority: Integration-specific.

Status (2026-08-18): ❌ Cut for v1 — roadmap cut list (sharing & collaboration); remains phase 2 scope.

Notebook access model:

Role	Suggested rights
Owner	Full control
Editor	Change sources, notes and artifacts
Viewer	Read/query shared notebook

Capabilities:

invite another user
revoke access
public/private state
share link
artifact-specific link
read-only access
public Chat View

Gemini Notebook supports public notebook links and distinguishes owner/editor access from viewers.

Priority: Post-MVP.

SF-06 — Public Notebooks

Status (2026-08-18): ❌ Cut for v1 — falls under the sharing & collaboration cut (roadmap cut list).

Users may publish a notebook that other users can:

open
inspect
query through chat
browse sources
consume generated artifacts

Priority: Optional.

SF-07 — Featured / Curated Notebooks

Status (2026-08-18): ❌ Cut for v1 — explicitly out of initial scope (§9: public featured-notebook marketplace).

A discovery surface can expose prebuilt notebooks curated by the application or partners.

Priority: Out of initial scope.

Status (2026-08-18): 🔶 Partial — download, rename, regenerate and delete on private signed URLs shipped for audio artifacts (D2, #27); no share or public links (sharing cut for v1).

Where appropriate, generated artifacts should support:

download
copy link
share with notebook members
public link
revoke link
rename
delete

Audio, video, infographics and mind maps currently expose various combinations of these capabilities.

SF-09 — Background Generation Jobs

Status (2026-08-18): 🔶 Partial — async generation with status-column polling shipped (feasibility D-2 stage 1; A3/D2, #15, #27); no queued, recoverable job infrastructure yet.

Long-running artifact generation must not block the application.

A job can be:

Queued
→ Processing
→ Completed

or

Queued
→ Processing
→ Failed

Users should be able to leave the current view while audio, video, reports or other artifacts generate.

Google explicitly performs Audio, Video and Infographic generation in the background.

MVP: Required once asynchronous artifact generation exists.

SF-10 — Language Configuration

Status (2026-08-18): 🔶 Partial — Audio Overview output language is selectable (German/English; D2, #27); multilingual output elsewhere is on the roadmap cut list.

Users can configure output language independently of source language.

This affects:

chat
reports
audio
video
visual artifacts
study material

Gemini Notebook supports multilingual output, including Audio Overviews in more than 80 languages.

Priority: International product: High.

SF-11 — Usage Limits and Quotas

Status (2026-08-18): 🔶 Partial — guard limits shipped (20 MB/file, 200k words/source, 50 sources/notebook, 20 artifacts/notebook, 1 concurrent generation; A3/D2, #15, #27); per-user quotas shipped (20 notebooks/user, 50 chat messages/notebook/day, 10 audio overviews/user/day — service-layer enforcement via repository counts; A6, #49); no request-RATE limits on app actions — tracked as SEC-7 in product/security.md.

Limits may apply to:

notebooks per user
sources per notebook
source size
chat messages
artifact generations
audio generations
video generations
research jobs
model usage

These can vary by subscription tier.

For reference, Gemini Notebook currently applies different limits according to account tier.

MVP: Required for operational cost control even without subscriptions.

SF-12 — Subscription / Feature Entitlements

Status (2026-08-18): ❌ Cut for v1 — commercialisation is out of v1 scope (this item is “required only if commercialisation is in scope”).

Potential plans:

Free
├── Base notebooks
├── Limited sources
├── Limited chats
└── Limited generations

Pro
├── Higher quotas
├── Advanced models
├── Research
├── Code execution
└── Advanced artifact generation

Priority: Required only if commercialisation is in scope.

SF-13 — Usage Analytics

Status (2026-08-18): ❌ Cut for v1 — roadmap cut list (analytics).

Owners of shared/public notebooks may see:

viewers
notebook usage
interaction counts
popular content
aggregate usage trends

Gemini Notebook offers analytics for qualifying shared notebooks.

Priority: Optional.

SF-14 — Feedback

Status (2026-08-18): ⏳ Planned (no phase assigned yet) — not shipped, and not on the roadmap cut list.

Users should be able to rate:

chat responses
generated mind maps
audio
video
visual artifacts

Possible controls:

👍 Useful
👎 Incorrect / irrelevant / unsafe

Feedback should attach generation context where privacy policy permits.

Google uses explicit thumbs-up/thumbs-down mechanisms across multiple Notebook artifact types.

Non-functional status (2026-08-18): the NF sections below are not badge-tracked per item. The living record of the non-functional side is the security register (product/security.md, repo-only), the feasibility register (decisions D-1…D-10 and risk rows), and the architecture views, which describe the system as deployed.

7. Non-Functional Requirements

NF-01 — Grounding and Provenance

The system must strongly prefer notebook evidence over unsupported model knowledge.

Requirements:

retrieval constrained to selected sources
claims traceable to source passages
citation metadata preserved throughout generation
source selection respected
no fabricated citations
clear behaviour when evidence cannot be found

For a NotebookLM clone, this should be considered a primary quality metric, rather than a secondary feature.

NF-02 — AI Accuracy

Generated output must minimise:

hallucinated claims
incorrect attribution
fabricated quotations
citation mismatches
misleading synthesis

Automated evaluations should test both answer correctness and citation correctness separately.

NF-03 — Response Latency

Suggested targets:

Operation	Target
UI interaction	<100 ms perceived
Chat starts streaming	<2–4 s
Citation/source opening	<500 ms
Search within indexed sources	<1 s
Basic source ingestion	progressive
Heavy artifact generation	asynchronous

Heavy generation should favour asynchronous jobs over blocking requests.

NF-04 — Scalability

The architecture should scale independently across:

file ingestion
document parsing
embedding/index generation
retrieval
chat inference
artifact generation
transcription
text-to-speech
image/video generation

Worker-based asynchronous processing is preferable for ingestion and generated artifacts.

NF-05 — Reliability

Requirements:

ingestion retry
generation retry
recoverable jobs
idempotent processing
persistent job state
graceful model/API failure
timeout handling
partial failure handling
corrupted-source isolation

A failure processing one source must not corrupt the notebook.

NF-06 — Data Durability

Persist:

notebooks
sources
source metadata
extracted representations
notes
chat history
artifacts
citation mappings
user preferences
access permissions

Backups and restoration procedures should exist for persistent user data.

NF-07 — Security

Minimum controls:

TLS in transit
encryption at rest
isolated user/tenant data
authenticated file access
signed/private artifact URLs
role-based access control
CSRF/XSS protections
upload validation
malware scanning
rate limiting
secure secrets management

NF-08 — Privacy

The product handles potentially sensitive private documents.

Requirements:

explicit privacy policy
clear model-provider data policy
user-controlled deletion
account deletion
source deletion
data-retention policy
no model training on private user content by default
transparent subprocessors
private notebooks by default

Google similarly treats notebook sources, outputs and chat history as the notebook’s knowledge base and states that Notebook content is not directly used to train foundational models unless users explicitly provide feedback.

For an EU-facing product:

GDPR lawful processing basis
Data Processing Agreements
right of access
right of deletion
data portability where applicable
retention controls
subprocessor transparency
international transfer safeguards
audit trail for access/permission changes where appropriate

NF-10 — Copyright and Content Rights

Users may import copyrighted content.

The product should therefore provide:

rights acknowledgement during import
abuse reporting
takedown process
restricted public sharing where required
moderation for publicly distributed notebooks

Google explicitly warns users against sharing copyrighted source material without appropriate rights.

NF-11 — Accessibility

Target:

WCAG 2.2 AA

Including:

full keyboard navigation
screen-reader support
semantic controls
focus management
adequate contrast
transcript availability for audio/video
non-visual alternatives to diagrams where practical

NF-12 — Responsive Design

At minimum:

modern desktop browsers
tablet-compatible responsive interface

Native mobile applications should be considered a separate scope item.

NF-13 — Internationalisation

Architecture should separate content from interface strings and support:

UTF-8 throughout
locale-aware formatting
translated UI
independent source/output languages
RTL layouts where applicable

NF-14 — Observability

Operational monitoring should cover:

request latency
LLM latency
model failures
retrieval quality
token consumption
generation costs
ingestion failures
queue depth
worker health
storage usage
artifact failures
citation coverage

Tracing an AI request through:

User prompt
→ retrieval
→ selected chunks
→ model invocation
→ response
→ citations

is particularly important for debugging incorrect AI answers.

NF-15 — Cost Control

Status (2026-08-18): 🔶 Partial — per-user quotas (notebooks, daily chat messages, daily audio generations; A6, #49), maximum file size / source count / artifact count and 1-concurrent-generation guards (A3/D2, #15, #27). Open: token budgets, model routing, caching, storage quotas, request-rate limiting (SEC-7/SEC-10 in product/security.md).

AI and media workloads require explicit safeguards.

Include:

per-user quotas
token budgets
model routing
caching
generation limits
maximum file size
maximum source count
background-job concurrency limits
storage quotas
rate limiting

Video and interactive voice generation should be separately budgeted because their cost profile differs dramatically from text RAG.

NF-16 — Provider Abstraction

Where practical, product logic should not depend directly on one LLM vendor.

Separate interfaces should exist for:

embeddings
LLM inference
speech recognition
speech synthesis
image generation
video generation
reranking
web search

This reduces vendor lock-in and allows cheaper or stronger models to be substituted by workload.

NF-17 — Safety

Generated output and public content should be subject to:

model safety controls
upload abuse prevention
prompt injection mitigation
malicious-document isolation
public-content moderation
abuse reporting
appropriate restrictions on executable code

Prompt injection from imported webpages and documents is particularly relevant because source material is inherently untrusted input.

8. Recommended Product Scope

A full 2026 Gemini Notebook clone is a substantial product. It combines several products that could independently constitute SaaS offerings.

A sensible implementation boundary would therefore be:

Phase	Scope
Phase 1 — Core MVP	Notebooks, PDF/doc/text/web sources, source processing, grounded chat, citations, source viewer, source selection, chat history, notes
Phase 2 — NotebookLM Experience	Reports, Audio Overview, source discovery, improved notes, labels, sharing, multilingual output
Phase 3 — Learning & Visual Studio	Mind maps, flashcards, quizzes, infographics, slide decks
Phase 4 — Multimedia	Advanced podcast formats, interactive audio, Video Overviews
Phase 5 — Agentic Notebook	Deep Research, code execution, charts, spreadsheets, arbitrary document/artifact creation

The smallest product that genuinely captures NotebookLM rather than simply being another RAG chatbot is Phase 1.

The feature combination that creates the characteristic NotebookLM experience is:

Notebook → Sources → Retrieval → Grounded Chat → Inline Citations → Source Navigation → Notes

Audio Overview is then the strongest differentiating feature to add once that foundation works.

9. Explicit Initial Out-of-Scope Candidates

Unless strict feature parity is required, the following should initially be excluded:

native mobile apps
Gemini ecosystem integration
Google Search AI Mode integration
public featured-notebook marketplace
real-time collaborative editing
Cinematic Video Overview
interactive voice hosts
arbitrary cloud code execution
full Office document-generation suite
advanced notebook analytics

These features substantially increase scope without improving the essential source-grounded research loop.

10. Core Product Model

The underlying domain model can be reduced approximately to:

User
 └── Notebook
      ├── Sources
      │    ├── Original content
      │    ├── Parsed content
      │    ├── Chunks
      │    └── Retrieval index
      │
      ├── Conversations
      │    └── Messages
      │         └── Citations
      │
      ├── Notes
      │
      ├── Artifacts
      │    ├── Report
      │    ├── Audio
      │    ├── Video
      │    ├── Mind Map
      │    ├── Quiz
      │    ├── Flashcards
      │    ├── Infographic
      │    └── Slide Deck
      │
      └── Permissions

Conceptually, everything revolves around the notebook’s source corpus. Chat, notes, research and Studio artifacts should all consume the same source/retrieval layer rather than creating separate knowledge systems.

That architectural property is more important to reproducing NotebookLM than copying its user interface.

Product scope

Implementation status (as of 2026-08-18)

Gemini Notebook / NotebookLM Clone — Product Scope

1. Purpose

2. Core Functional Features

CF-01 — Notebook Management

CF-02 — Source Ingestion

Supported source categories

CF-03 — Source Processing and Knowledge Indexing

CF-04 — Source Viewer

CF-05 — Source Selection / Context Control

CF-06 — Grounded AI Chat

CF-07 — Inline Citations

CF-08 — Conversation State

CF-09 — Chat Configuration

CF-10 — Notes

3. Core Generated Artifacts / Studio

CF-11 — Reports

CF-12 — Audio Overview

Interactive Audio

CF-13 — Mind Maps

CF-14 — Flashcards

CF-15 — Quizzes

CF-16 — Infographics

CF-17 — Slide Deck Generation

CF-18 — Video Overview

4. Research Features

CF-19 — Web Source Discovery

CF-20 — Deep Research

5. Advanced Agentic Capabilities

CF-21 — Code Execution

CF-22 — General Artifact/File Generation

6. Supporting Functional Features

SF-01 — Authentication and Account Management

SF-02 — Notebook Library / Home Screen

SF-03 — Source Organisation

SF-04 — Cloud Source Synchronisation

SF-05 — Sharing and Collaboration

SF-06 — Public Notebooks

SF-07 — Featured / Curated Notebooks

SF-08 — Artifact Sharing and Download

SF-09 — Background Generation Jobs

SF-10 — Language Configuration

SF-11 — Usage Limits and Quotas

SF-12 — Subscription / Feature Entitlements

SF-13 — Usage Analytics

SF-14 — Feedback

7. Non-Functional Requirements

NF-01 — Grounding and Provenance

NF-02 — AI Accuracy

NF-03 — Response Latency

NF-04 — Scalability

NF-05 — Reliability

NF-06 — Data Durability

NF-07 — Security

NF-08 — Privacy

NF-09 — GDPR / Regulatory Compliance

NF-10 — Copyright and Content Rights

NF-11 — Accessibility

NF-12 — Responsive Design

NF-13 — Internationalisation

NF-14 — Observability

NF-15 — Cost Control

NF-16 — Provider Abstraction

NF-17 — Safety

8. Recommended Product Scope

9. Explicit Initial Out-of-Scope Candidates

10. Core Product Model