I added something to my Claude Code today that Anthropic never built.
Look at the line the arrow points to: git main | up 1m 46s | tools 2.
Claude Code doesn’t come with that line. I typed one sentence in plain English, and Claude built it.
It shows my git branch, how long my session has been running, and how many actions Claude has taken.
By the end of this issue, you’ll have yours.
It’s called a mod. Since October 1, anyone can build one.
A mod rewrites Claude Code itself. It can add a live panel beside your chat, hold a dangerous command before it runs, or hide your API keys before Claude reads them.
Three things in the docs stopped me cold:
Anthropic already rebuilt one of its own features as a mod. You can switch it off and use yours.
The mods Claude builds for you get deleted on a timer. Most people won’t notice until theirs is gone.
A stranger’s mod can approve Claude’s actions without asking you.
Below, I’ll show you which feature, how to save your mods, and the one-minute check that exposes what any mod can do.
Paid members also get The Mod Vault: 30 copy-paste mod prompts, a safety checklist, and a fix card for when a mod won’t show up. It’s open for one week.
Why This One Matters
Until last week, you could teach Claude new tricks (skills), give it new tools (MCP servers), and run scripts on certain events (hooks).
All of that worked from the outside.
Claude Code itself stayed the same app for everyone.
Mods run inside it.
They can redraw what you see, step into a tool call before it happens, and add commands that run instantly, even while Claude is busy.
I read every page of the official docs and the most popular mods guide going around this week.
The guide was good, but it skipped the three things that bite beginners: why your mod vanishes, how to check a mod before installing it, and when you should build a skill instead.
This issue covers all three.
Who You’ll Be After This Issue
→ You’ll see which mods Anthropic already put on your machine.
→ You’ll know in 30 seconds whether your idea should be a mod at all.
→ You’ll build your first mod in about five minutes by describing it.
→ You’ll keep it for good, before Claude Code deletes it.
→ You’ll check any stranger’s mod before it touches your files.
→ You’ll switch any mod off in seconds.
You don’t need to know JavaScript. You need Claude Code and one evening.
I spent my whole day at this desk, testing every step below until it worked, so you won’t hit a single error. If that effort saves you an evening, I think I’ve earned a coffee from you. ☕
Everything Below Is for Paid Members
→ The hidden mod Anthropic is quietly testing, and the command to try it.
→ The 30-second test that tells you if your idea should be a mod or something simpler.
→ The 5-minute first build. One prompt, one mod, live on your screen.
→ The keep-it prompt that stops your mods from being deleted.
→ The audit prompt. Claude reads your past sessions and tells you which mods you need.
→ The safety check that lists everything a mod can touch, with a practice run on Anthropic’s own sample mod.
→ The off switch for one mod, or all of them.
→ The Mod Vault: 30 mod prompts, the safety checklist, and the fix card.
