The inline diff approach for AI edits is a smart design choice. Most AI writing tools either do the sidebar chat thing (context-disconnected) or full rewrites (terrifying). Showing each change as a reviewable diff keeps the human in control without adding friction.

Question about the knowledge base: when it pulls from uploaded PDFs and cites sources, how granular are the citations? Page-level? Paragraph-level? For research-heavy writing, the difference between "this came from your uploaded paper" vs "this came from page 12, paragraph 3 of your uploaded paper" is huge for trust.

The $2.99/month early-bird is aggressive pricing. At that price point the unit economics only work if AI usage per user is relatively low - have you modeled what happens if power users start running heavy AI workflows across large documents? BYOK helps here but most casual users will not bring their own key.

One thing that might strengthen the positioning: the "lighter than Notion" framing undersells it a bit. You are not just Notion-minus-features, you are building something Notion cannot easily bolt on - deep document-native AI with provenance tracking. That is a genuinely different product category.