Claude Code for Investment Research (Part 4): The Obsidian Layer That Makes Everything Compound

How to make Obsidian the brain that holds every article, every concall, and every market thread you've ever read. The layer that makes Claude Code compound instead of forget.

Ninety days ago, I opened a terminal for the first time and typed claude. Today, the same stack runs my entire investment research workflow. Screening, scraping, modeling, drafting, monitoring. The terminal stopped being intimidating somewhere around day three.

Three newsletters in, you’ve seen most of the moving parts. Part 1 was the confession, why a finance guy would even open a terminal in the first place. Part 2 was the full setup: Claude Code, Cursor, Obsidian, Playwright, Firecrawl. Part 3 was the first real workflow, decoding insider trades.

If you’re new here, those three are worth reading before this one. They build the system. This newsletter is about the part of that system most readers underestimate, and the part doing the most quiet work in the background.

Obsidian.

1. The Bottleneck Was Never the AI

Picture a Monday morning. You’re scrolling X with your coffee. Someone shares a research piece on the semiconductor capex cycle. You read it. It’s good. You make a mental note that this’ll matter for the chip names on your watchlist.

Friday rolls around. You’re researching one of those names. You remember the article. You don’t remember where you saw it. You scroll X for ten minutes. You search your bookmarks. You give up. You do the analysis without it.

Multiply that by six months of reading. That’s the real bottleneck in AI-powered research. Not the AI. The collection.

Every analyst I know has tried to build a personal research library. Most have failed. The reason isn’t laziness. It’s that the act of filing is exhausting. Bookmark the page. Open a folder. Rename the file. Pick a tag. Upload it somewhere. Six months later, find it again. The first time you do it, it takes ninety seconds. The fifth time you do it that morning, you stop doing it.

The AI tools we’ve been talking about in this series, Claude Code, NotebookLM, the rest of the stack, all assume you’ve solved this problem. They assume the right document is already in the folder when you ask the question. They don’t help you put it there.

That’s the gap.

Now picture the same Monday. You read the same article. You hit one button in your browser. The article is already a markdown file in your research folder. You didn’t pick a name. You didn’t pick a tag. You didn’t decide where it goes. Friday comes. You ask Claude Code: what have I read on this sector recently? It pulls the article. It pulls the concall transcript you clipped three weeks ago. It pulls the chart you saved last month.

Now zoom out. Six months. A year. Two years.

Every article you’ve ever read. Every concall. Every chart. Every newsletter. Every X thread. All in one folder, all in markdown, all readable by Claude Code in a single query.

Your research stops disappearing. It starts compounding.

That’s what Obsidian does. The next sections are about how.

2. Obsidian, In One Paragraph

Obsidian is a free app. You download it. It points at a folder on your computer. Every note you create is a plain text file inside that folder, written in markdown. The folder is the product.

That sounds boring until you realize what it means. Markdown is the format AI models read most easily. Plain text on disk is the format Claude Code can write to, edit, and search without any bridge or API. A folder of markdown files is, by default, the most AI-friendly research library you can build. Obsidian’s only job is to make that folder pleasant to live in: a sidebar, a search bar, a graph view of how your notes connect, a plugin system for the things the core app doesn’t do.

If you read Part 2 of this series, you’ve already installed it. You created a vault with three folders, raw/, wiki/, and output/, plus a CLAUDE.md rulebook that tells Claude Code how to behave inside it. If you haven’t done that setup yet, do it now, 10 minutes of work, and the rest of this newsletter assumes it’s in place.

Prefer to watch? I recorded a forty-three-minute walkthrough of the entire system, including live use cases and the parts that are hard to show in writing. The newsletter stands alone, but the video shows what the screen looks like.

What I want to spend the rest of this piece on is what happens after the install. Because Obsidian by itself is just a note-taking app. Obsidian wired into Claude Code, with one browser extension and one design principle, is the part doing the quiet work in the background.

The browser extension is called Web Clipper. The design principle is that you don’t decide where anything goes. You’ll see what I mean.