Nº 01 — Claude AI
Claude Lab
Collaboration with linguistic intelligence, distilled into method.
A knowledge base for Claude.ai, Claude Code, Cowork and the Claude API. Written for everyone from people meeting Claude for the first time to those who have built it into development and daily operations, it records what I have confirmed in actual work.
The more I hand over, the more there is to confirm.
About
I now build apps and run websites together with Claude. I sort out ideas in conversation, have Claude Code write the code, and let Cowork take on manual tasks. Along the way, I sometimes stop at places I never expected.
Claude Lab is where I keep what I looked up, tried and understood in those moments. Each article traces what happened, where I looked and how I fixed it, so that whoever stumbles at the same spot months from now, even if it is me, can find the way out quickly.
The top of the site lists model retirements and new releases with their dates. Because Claude changes month by month, you can check what is about to change before you read. Articles are marked beginner, intermediate or advanced, and three guides let you read in order from the beginning.
Every article comes with the code I actually ran. In-depth guides that go as far as my own measurements and the designs I use in production are available to members as premium articles. The site can also be read in Japanese.
What It Covers
- Claude.aiUsing the web and mobile apps
- Claude CodeAI coding assistance from the terminal
- CoworkDesktop automation and task management
- API / SDKAPI integration for developers
Recent Articles
A few examples of what I write.
- Beginner
Cowork or Claude Code: where to start
For readers who have never opened a terminal: deciding by three questions, namely the shape of the result, how easily a mistake can be undone, and who will check it.
Read the article ↗ - Intermediate
Checking a spreadsheet Cowork built against the source
After handing over transcription such as invoices, a short script that catches missing rows, swapped digits and amounts left as text.
Read the article ↗ - Intermediate
When a valid key still returns 400 or 401
Two causes to suspect before regenerating your API key, with a triage table by error message and a script you can run yourself.
Read the article ↗
Systematic Guides
Articles are arranged into three guides you can follow in order from the beginning.
- Beginner
The Complete Guide to Claude
Start here if you are new
- Intermediate to advanced
Prompt Engineering Compendium
Writing that draws out what Claude can do
- Intermediate
Claude Code Practical Handbook
AI-driven development from the terminal
Reading
Claude Lab is free for anyone to read, with no advertising. In-depth guides with implementation code are available to members as premium articles.
Read Claude Lab
More Labs
Gemini LabMultimodal intelligence, brought to bear on the precision of thought and craft.→
Antigravity LabA critical record from the front line of autonomous-agent design.→
Rork LabA methodology of application development with Rork Max.→