A note from the maker

I built Jeff because I wanted to use it.

The first version ran on my laptop, on a Wednesday, three days into a thesis on a chip stock I was about to size up. I had eight tabs open and no opinion yet. Jeff is what I wanted running in the background. Now it does, and you can use it too.

Upamanyu Acharya · Retail US-equity investor since 2021 · Mumbai

Jeff, holding the kind of research note this tool produces. — Jeff. He doesn't sleep. He doesn't charge a retainer. He also isn't real.

Why this exists

I've been buying individual US stocks since 2021. The kind of investing where you actually have to have a view on gross-margin trajectory, not the kind where a fund manager handles it for you. Four years and counting, through the 2022 drawdown and everything since.
The honest version of a research note takes me six hours. Read the 10-K. Read the last two transcripts. Pull a peer set. Build a quick DCF. Sanity-check against sector positioning. Most weekends I don't have six hours. I have ninety minutes between dinner and bedtime.
Around 2023 I noticed I was doing most of that work inside Claude. Reading filings, comparing peers, pressure-testing my thesis. The model wasn't replacing my judgment. It was eating the bottom 80% of the funnel that nobody enjoys.
So I built that 80% as code. First as a private Claude Code skill I'd run on tickers I owned. Then this: a five-stage pipeline that pulls fundamentals, places the stock inside its sector, builds bull/base/bear scenarios, overlays a macro regime view, and writes the thing up.
Jeff runs that pipeline on demand. Same five stages, same order, any ticker. Every number it cites is fetched from a live API while you watch. If a quote looks wrong, it probably is. Tell me.

What I tried to make different

Numbers are pulled, not invented. Yahoo Finance for prices, Financial Modeling Prep for fundamentals, Brave for news, a community CSV for sector rotation. The model writes the analysis around the data. It does not make up the data.
The verdict is in the first 200 words. Rating, conviction (1 to 5), price target range. Argue with it from there. The supporting work sits below for when you want to.
You watch the work happen. Every tool call, every line of reasoning, every stage hand-off. A black box that thought for five minutes and said BUY is the exact thing I built this to avoid.
Nothing lives on the server. No accounts, no analytics scripts, no chat-history table. Your threads are in your browser. Clear cache and they're gone.
I pay for the tokens. A full report costs about fifteen cents. While the project is small enough that I can absorb that, it's free for you.

What I'm doing next

Jeff is the third tool I've shipped this year. The pattern I keep returning to: take something I do badly by hand, hand it to a model that does it well, and put a clean interface on top. There will be more in this shape.
I'm not going to share my picks. I will share the method. If a friend wants my view on a name I happen to own, I'd rather hand them Jeff than a Telegram screenshot.
If something breaks, tell me. The bugs are real and I want to hear about them. Find me via the contact form on upamanyuacharya.com or on LinkedIn.