Deny

The list of actions that Claude is never allowed to take, for example reading the passwords. The prohibition always wins.

You’ll also find it as: deny list

How it appears in the course

"deny" — the list of things that are forbidden. Here: reading the .env file (where passwords and secret keys are usually kept), the secrets folder, forced deletion (rm -rf) and downloading from the internet (curl).
What does a real settings file look like? · Module 03, Permissions: what Claude may do
The order in which Claude checks the rules: deny → ask → allow. First it looks at the prohibitions. If something is forbidden, it’s forbidden, even if it also appears in the “allow” list. Deny always wins.
How are the rules written? · Module 03, Permissions: what Claude may do
allow = does it on its own, ask = asks you, deny = forbidden. Deny always wins.
Key takeaways · Module 03, Permissions: what Claude may do

Where you learn it

In module 03 · Permissions: what Claude may do, in the Claude Code for Beginners course.

Related terms

.envacceptEditsAllowlistbypassPermissionsContainerEnvironment variable

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