At most one email a week. Unfollow anytime with one click.
Transcript
The full narration of this video. The current sentence is highlighted while the video plays; click any sentence to jump there.
Show transcript
Introduction
Hi, and welcome back. This is the last episode of the Introduction to Claude Code session, and we're going to create one small file with a big impact. It's called CLAUDE.md: standing notes that Claude reads every time it starts working. We'll create it, fill it with Sunset Coffee's data, and then test it.
Step 1: The problem: Claude forgets in a new conversation
Imagine the next day. Raka opens Claude Code again in the same folder. The conversation starts from scratch. Raka immediately asks for a call to action for the gift hamper, as if Claude still remembered yesterday's chat. Instead, Claude asks back: how much is it, should the tone be formal or casual, and which page is this for? That's fair, because yesterday's chat didn't carry over. Re-explaining every day would be exhausting. The solution is CLAUDE.md. It's an ordinary text file saved in the project folder. Every time Claude Code starts working in that folder, this file is read automatically. The dot m d extension means Markdown format: plain text with a hash sign for headings and a minus sign for lists. Easy for people to read, and easy for Claude too. For Dewi at Maju Bersama Co., it could hold the wholesale price list and the report format. For Mr. Hendra at Cerdas Tutoring, it could hold rules for question difficulty levels. Every project has its own notes. The idea is similar to the Projects instructions we learned in the Projects session. The difference is that Projects instructions live in Claude on the web, while CLAUDE.md is a file in the project folder. Projects instructions are used by chats inside that Project. CLAUDE.md is used by Claude Code every time it works in that folder. The contents are similar too: business data, writing style, and work rules. Because it's a file, CLAUDE.md is saved with the project and gets copied along if the folder is moved.
Step 2: Creating CLAUDE.md with /init
The easiest way to create it is the slash init command. Raka types it in the prompt box and presses Enter. Claude reads the project files first: the menu, the Sunset Coffee story, the welcome page, and others. Seven files in total. From what it read, Claude writes a draft CLAUDE.md that's fourteen lines long. Like any other file, Claude asks permission before saving. Raka chooses Yes. Claude explains what's in the draft: a project overview, a list of key files, and where the photo folder is. It also reminds us that the draft needs filling in. To be useful, CLAUDE.md should have four parts. First, about the project: one or two sentences saying this is the Sunset Coffee website for customers in Bandung. Second, business data: official prices, shipping rules, opening hours, and contact details. This is the data used most often, and the most dangerous if it's wrong. Third, style: friendly, casual language, plus the brand colors of coffee brown and cream. Fourth, work rules: for example, always ask before deleting a file, and summarize every change. The draft from init usually only has the first part, so we add the other three ourselves. It doesn't have to be perfect on day one. CLAUDE.md grows with the project: every time there's an important decision, we add a line.
Step 3: Adding business data and work rules
Raka asks Claude to add a business data section: prices taken from the menu file, plus the shipping rule and opening hours. Claude uses Edit to add a few lines to CLAUDE.md. Look at the change box. There's a business data heading with a hash sign, then a list of prices, shipping, and opening hours with minus signs. All the lines are green, meaning they're only additions. Raka checks every number against Laras's list. Eighteen thousand, eighty-five thousand, fifty-five thousand, one hundred fifty thousand: all correct. Raka chooses Yes. Next, Raka adds the style and work rules in one instruction: casual language, coffee brown and cream colors, ask before deleting, and a three-point summary at the end of each task. The change box shows two new sections: style, then work rules. The sentences are short and clear, so Claude can follow them easily. Raka chooses Yes. CLAUDE.md now has all four parts. The whole thing is only about twenty-five lines, but it saves a lot of re-explaining.
Step 4: Testing in a new conversation
Now for the test. Raka clears the conversation with slash clear, so Claude truly starts from zero. Then Raka sends exactly the same instruction as yesterday: write a call to action for the gift hamper. No price, no style mentioned. This time Claude doesn't ask. The sentence is casual, the hamper price of one hundred fifty thousand rupiah is right, and the free shipping rule above two hundred thousand is mentioned too. Claude also ends with a three-point summary, as the work rules say. Notice the third point: no files changed yet. That means CLAUDE.md is working well. Compare the results. Before CLAUDE.md, Claude asked three questions back for one simple instruction. Afterward, there were no questions back at all, and the data was exactly right. All that from about twenty-five lines of notes read automatically. It's a small investment that keeps paying off throughout the project.
Step 5: Maintaining CLAUDE.md
To keep it useful, maintain CLAUDE.md like an SOP. First, keep it short and concise. Notes that are too long actually make things harder. Second, update it right away when prices or rules change. If Laras raises a price, CLAUDE.md should be changed that same day. Third, ask Claude to record new decisions. Just say, record this decision in CLAUDE.md, then read the change before approving. Fourth, reread it once a month and remove anything outdated, such as a promo that has ended. Fifth, never include passwords, secret keys, or customer data. CLAUDE.md gets copied wherever the project goes. Here's an example of recording a new decision. Laras decides every order button should open the business WhatsApp, not a phone call. Raka asks Claude to record it in CLAUDE.md. Claude uses Edit and adds just one line. A small change like this is quick to read. The change box shows the context: gray lines are the existing rules that stay, and the green line is the new decision below them. Raka chooses Yes. From now on, every order button Claude builds will point to WhatsApp without needing a reminder. Finally, there are two levels of CLAUDE.md. The one we just made is the project CLAUDE.md. It lives in the project folder, and its contents are just for Sunset Coffee. There's also a personal CLAUDE.md that applies to all your projects, for example always answering in simple language. Where that file lives is in the official Claude Code documentation, because it can change. The screens in this video are simulations, and the details may differ slightly. With CLAUDE.md, our tools and work habits are complete. The Sunset Coffee project is ready to build with a Claude that already understands the business.
Done!
That wraps up the Introduction to Claude Code session. We've installed Claude Code, given instructions, understood permissions, and now have a CLAUDE.md with Sunset Coffee's data and rules. In the next episode we start the Building a Website session: Raka builds the Sunset Coffee landing page from the plan and materials we've prepared. See you there!
Practice exercises
Try these on your own after watching to lock in what you learned.
Create a CLAUDE.md for your project with /init
Add the three most important pieces of business data and three work rules
Start a new conversation, then test whether Claude uses that data without being reminded
Ask the class material
Type a question or keyword; we find the part of this episode that explains it and jump the video there.
My notes
Notes are saved with the current video time and are only visible to you.
Questions & answers
Stuck on a step? Ask here; the instructor and other learners can answer.
No questions yet.
Your instructor
Cerdas Inovasi Digital Team
Software developers, BIM & 3D engineers, and AI practitioners
52 video classes1,277 episodes
We build software, BIM models, games and AI automations for clients every day, and turn that hands-on work into step-by-step classes: every step is shown on screen and comes with a PDF guide you can keep.
