> ## Content Index > Fetch the complete content index at: https://www.jeffsu.org/llms.txt > Use this file to discover other available public pages before exploring further. # How to turn PDFs into lightweight AI reference files - URL: https://www.jeffsu.org/newsletter-268/ - Published: 2026-10-16T02:01:44.000Z - Updated: 2026-10-16T02:01:44.000Z - Description: #268 - Author: Jeff - Tags: #newsletter, Claude, ChatGPT, Gemini, #hide-tag Want to see these tips early? [Subscribe to the newsletter!](https://www.jeffsu.org/newsletter/) --- If you use Projects in Claude or ChatGPT, you’ve probably uploaded a PDF as a reference file at some point (a company handbook, a style guide, a 60-page industry report, etc). Technically, there’s no real issue with that, BUT you’re giving your AI **an entire dense document to work with**, even when you only need two pages of it. ![A dense PDF attached as a reference in a Claude Project.](https://storage.ghost.io/c/db/85/db858a9d-1c4f-4993-8042-faa87b9bb3c1/content/images/2026/10/ae268-dense-pdf-project-context.png) What you want to do instead is **ask your AI to pull out just the parts that are relevant to you and save them as a lightweight Markdown file.** The result can be 90% smaller than the original, with far less text to load and process. That can save tokens and get you what you need MUCH faster. ## What I actually need from a 42-page tax guide Here I have Hong Kong’s 42-page tax guide, which covers every tax the Inland Revenue Department handles (a real page-turner, highly recommend). ![Hong Kong’s tax guide contains 42 pages covering different taxes.](https://storage.ghost.io/c/db/85/db858a9d-1c4f-4993-8042-faa87b9bb3c1/content/images/2026/10/ae268-hong-kong-tax-guide.png) As an entrepreneur with no personal income, only a few sections of this guide actually apply to me, so there’s no reason to give my AI the ENTIRE PDF for every tax-related task. Instead, **I want it to extract just the portions that are relevant to me into one Markdown file**, which becomes the reference for those tasks. ## How to turn any PDF into a reference file 1. **Upload the PDF to any chat and paste the prompt below.** Fill in who you are and what you’ll use the file for, so the AI knows what to keep. 2. **Save the result as a Markdown file and replace the PDF in your Project’s reference files.** That’s “Context” in Claude, “Sources” in ChatGPT or a Gem’s “Knowledge” in Gemini. Keep the original PDF separately so you can check or update the extract later. 3. **Update your Project’s instructions.** Tell the AI to use the Markdown file as its reference for that topic. ### Here’s the prompt ``` I've attached [document name]. I'm [your role and situation], and I'll use this as a reference for [the questions or tasks you'll bring to it]. Extract only the parts that apply to my situation into a Markdown file. Use clear headings, keep exact numbers, dates and definitions, and note the page each item comes from so I can check it against the original. Leave out everything that doesn't apply to me. ``` ![Relevant sections from a dense PDF become a short Markdown reference.](https://storage.ghost.io/c/db/85/db858a9d-1c4f-4993-8042-faa87b9bb3c1/content/images/2026/10/ae268-pdf-to-markdown-reference.png) ## What if I use an AI System? If you’re using an AI system like **ChatGPT Work, Codex, Claude Code, or Google’s Antigravity**, the logic is exactly the same: 1. Extract the relevant parts of a dense source into a lightweight Markdown file. 2. Update your main instructions file, such as CLAUDE.md or AGENTS.md, to use that Markdown reference for the relevant tasks. 3. Keep the original in a “Source” folder so you can update the extract as your needs evolve. ![Original PDFs kept separately in a Source PDFs folder.](https://storage.ghost.io/c/db/85/db858a9d-1c4f-4993-8042-faa87b9bb3c1/content/images/2026/10/ae268-source-pdfs-folder.png) If you’re a student of [The Cowork Academy](https://coworkacademy.ai/?ref=jeffsu.org), you’ll recognize this as the Source PDFs workflow from **Lesson 2.05: The Reference Shelf: Load Only What You Need**. Pick one PDF that’s sitting in a Project right now (or one you keep re-uploading), run the prompt on it this week and let me know how it goes! 😁 --- **Whenever you’re ready, here are some other ways I can help you:** 💻 [The Workspace Academy:](https://academy.jeffsu.org/workspace-academy?ref=jeffsu.org) Never lose a file, task, or note again with my CORE workflow for Google Workspace. Adopted by over 10,000 Googlers. ✅ [Build Your Command Center in Notion:](https://www.pressplay.cc/link/s/D5B5EC96?ref=jeffsu.org) Plug-and-play dashboard that surfaces today’s priorities automatically and organizes your life in seconds. #1 rated Notion Course globally.