<aside> 📌 If Claude Code has been frustrating you lately, it's not in your head. The guy who built it literally told everyone on Hacker News how to fix it.

</aside>

What Actually Happened

Anthropic quietly changed two default settings in Claude Code. An AMD executive named Stella Laurenzo analyzed 6,852 Claude Code sessions and found a 67% drop in reasoning quality compared to earlier this year.

That's not a small dip. That's the tool operating at a fraction of its brain power — by default.

Boris Cherny, the actual creator of Claude Code, jumped on Hacker News to confirm the issue and gave everyone the fix. Here's exactly what changed and how to undo it.

Fix #1: Set Effort to Max

Claude Code used to default to high effort. Now it defaults to medium. That means it's literally not trying as hard on your tasks unless you tell it to.

Quick fix (per session): Open Claude Code and type:

/effort max

That's it. One command. You're now getting maximum reasoning power for that session.

Permanent fix: To make this stick across every session, add it to your settings file. Open (or create) the file at ~/.claude/settings.json and add:

{
  "env": {
    "CLAUDE_CODE_EFFORT_LEVEL": "max"
  }
}

Beginner tip: If you've never touched this file before, open your Terminal and paste this:

mkdir -p ~/.claude && echo '{"env":{"CLAUDE_CODE_EFFORT_LEVEL":"max"}}' > ~/.claude/settings.json

That creates the file for you. If you already have a settings file, just add the "env" section inside the existing curly braces.

Fix #2: Disable Adaptive Thinking

This one's sneakier. Claude Code now has something called "adaptive thinking" where it decides on its own whether your question deserves deep reasoning or not.

The problem? It sometimes decides not to think at all — even on complex tasks. Boris confirmed on Hacker News that certain turns had "zero reasoning emitted" while the model was supposed to be working hard. That's how you get hallucinated commit SHAs, fake API versions, and made-up package names.

The fix: Add this to the same settings.json file:

{
  "env": {
    "CLAUDE_CODE_EFFORT_LEVEL": "max",
    "CLAUDE_CODE_DISABLE_ADAPTIVE_THINKING": "1"
  }
}