A free, verified guide to Claude Code safety hooks: the pre-flight checklist, what each guard actually blocks, and how to prove it fires
Installing safety hooks for Claude Code takes about thirty seconds. Proving they actually block anything is the step almost everyone skips — and an unverified guard looks exactly like a working one. Free: the pre-flight checklist, what each guard really refuses, how to make one fire on purpose, and the install command that quietly hands you a frozen version.
Minimum price
Free!
$5.00
About the Book
You leave Claude Code running while you do something else. You come back and something is gone. That is the moment this manual is written against.
Hooks can stop the common ways it happens: a recursive delete, a hard reset, a secret going into a commit. Installing them takes about thirty seconds. But an installed guard and a working guard look identical from the outside, and almost nobody checks which one they have.
This is the short version of that check.
Chapter 1 — the pre-flight checklist. Four stages you can copy into your project: before the first session, before letting it run unattended, during, and after.
Chapter 2 — measure before installing. The audit is read-only. Nine findings on an empty project is a baseline, not a crisis; what matters is which of them are still there a week later.
Chapter 3 — what the guards actually refuse. The block messages, taken from the shipped hook definitions rather than from the documentation, followed by a section on what a hook cannot see at all.
Chapter 4 — prove they fire. Feed a guard the input it is supposed to refuse, and watch what comes back.
Chapter 5 — the npm package is the wrong one. It is frozen at 29.8.0 and lets three destructive commands through that the current code blocks. The obvious install command is the one that gets you that version.
Chapter 6 — after the session. An empty log of blocked commands means either that nothing dangerous was attempted or that nothing is matching, and from the outside those look the same.
Every command output printed in this book was run against a clean sandbox before publication, failures included, because a check that cannot fail is not a check.
It is the companion to cc-safe-setup, an MIT-licensed tool, and everything in it is also in that repository. You are not paying for secrets — and at a minimum price of zero, you are not paying at all. What you get is the parts that matter, in the order you need them.
What it is not: a guarantee. A hook sees one tool call at a time; it does not see intent. Chapter 3 says where the floor ends. If you want a book that tells you your agent is now safe, this is not that book.
About the Author
Everything I publish starts from something that actually broke.
I run Claude Code on real projects, often unattended, and I have lost work to it. The hooks in cc-safe-setup (MIT, open source) exist one per incident — each guard is there because of a specific thing that went wrong. The books are the write-ups: what failed, what the logs looked like, and what finally stopped it.
Two things I hold myself to. If a number in one of my books is not something I measured, it says so. And if a command is printed, the output beside it came back from an actual run — failures included, because a check that cannot fail is not a check.
I am not selling certainty. Most of what I know here, I learned by breaking my own setup.
Table of Contents
Within 60 days of purchase you can get a 100% refund on any Leanpub purchase, in two clicks.
See full terms...
We pay 80% royalties on purchases of $7.99 or more, and 80% royalties minus a 50 cent flat fee on purchases between $0.99 and $7.98. You earn $8 on a $10 sale, and $16 on a $20 sale. So, if we sell 5000 non-refunded copies of your book for $20, you'll earn $80,000.
(Yes, some authors have already earned much more than that on Leanpub.)
In fact, authors have earned over $15 million writing, publishing and selling on Leanpub.
Learn more about writing on Leanpub
If you buy a Leanpub book, you get free updates for as long as the author updates the book! Many authors use Leanpub to publish their books in-progress, while they are writing them. All readers get free updates, regardless of when they bought the book or how much they paid (including free).
Most Leanpub books are available in PDF (for computers) and EPUB (for phones, tablets and Kindle). The formats that a book includes are shown at the top right corner of this page.
Finally, Leanpub books don't have any DRM copy-protection nonsense, so you can easily read them on any supported device.
Learn more about Leanpub's ebook formats and where to read them
You can use Leanpub to easily write, publish and sell in-progress and completed ebooks and online courses!
Leanpub is a powerful platform for serious authors, combining a simple, elegant writing and publishing workflow with a store focused on selling in-progress ebooks.
Leanpub is a magical typewriter for authors: just write in plain text, and to publish your ebook, just click a button. (Or, if you are producing your ebook your own way, you can even upload your own PDF and/or EPUB files and then publish with one click!) It really is that easy.