Rules Are Who You Are, Skills Are What You Know, Prompts Are What You Want
Rules, skills, and prompts each have their own cost model, and filing instructions under the wrong layer is why agents feel either bloated or ignorant. A field guide to sorting the pile.
The Judge Does Not Run Your Tests
The judge model behind agent loops like Claude Code's /goal never runs your tests or reads your repo. It only reads the transcript, so verification is only as real as the receipts your agent produces.
Stop Being the Thing in the Loop
Boris Cherny writes loops that prompt the agent instead of prompting it himself. The job moved from writing code to writing the thing that writes the code, and only two properties make that loop trustworthy: an external check and hard stops.
Half of All Code on GitHub Is Now AI-Generated
GitHub reports 51% of committed code in early 2026 was AI-generated or AI-assisted.
Claude Code ultraplan separates thinking from doing
1. Ultraplan moves planning out of the terminal and into a browser. You get inline comments, structured review, and the ability to keep coding while the plan builds itself in the cloud. It sounds minor. It changes how you work.
Andrew Ng's career advice for AI practitioners, straight from Stanford
1. The constraint is shifting upstream. As code generation gets cheaper, the bottleneck moves from writing software to knowing what software to write. Engineers who talk to users directly are outpacing entire teams.
14 Things Anthropic Tells Claude NOT to Do, and Why You Should Steal Them as Your Own Coding Guidelines
The most useful part of Claude Code's 13,000-token system prompt isn't the identity framing or the tool descriptions. It's a section called "Doing tasks" that contains 14 explicit constraints on how code should be written.
Inside Claude Code's Prompt Architecture: What 28 Prompt Files Reveal About Building AI Coding Agents
Production-grade AI agents don't run on a single system prompt. They run on layered architectures of specialized instructions, each solving a distinct problem, composed at runtime based on context.
Your AI Coding Assistant Has a Pet: Inside Claude Code's Hidden Buddy System
Somewhere in a TypeScript codebase spanning half a million lines, an Anthropic engineer sat down and drew ASCII art of an axolotl wearing a wizard hat. Then they gave it stats.
Things I Learned from the Claude Code Source Code
The Claude Code CLI ships as a compiled binary, but the TypeScript source underneath is remarkably readable once you unpack it. I spent a week going through all 512,000 lines across 1,884 files, looking for the engineering decisions that reveal where
Cursor Just Crossed $2 Billion in Revenue. The Automations Feature Explains Why.
Cursor doubled its revenue to $2 billion in three months. Its new Automations feature shows where AI coding is headed.