source-lm

What is source-lm?

A Chrome extension that helps you add sources to NotebookLM in bulk instead of one at a time. It can turn JSON exports like Telegram chats, support-ticket dumps, URLs, YouTube videos, or selected page text into Markdown files and upload them straight into an open notebook. It keeps each record whole, budgets content under NotebookLM’s source limit, and skips items that were already uploaded on a later run. There’s no backend and nothing is written to disk, so everything is built in memory and sent directly from your browser. It also adds handy notebook tools like duplicate detection, batch delete, and a broken-source replacement flow.

Key features

• Splits large exports into Markdown files under NotebookLM limits.
• Keeps records whole and never splits one across files.
• Uploads only new records on repeat runs.
• Adds YouTube videos, playlists, and channel content in bulk.
• Lets you upload the current tab, links, or selected text.
• Finds duplicates, filters sources, and batch-deletes checked items.