.env

A hidden file in the project where passwords and secret keys are kept. It never goes into git, and it’s a good idea to forbid Claude from reading it.

You’ll also find it as: the .env file

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
Always forbid reading files with passwords, like .env.
Key takeaways · Module 03, Permissions: what Claude may do
Forbid reading .env. Then ask Claude to read .env and check that it refuses.
Try it yourself · 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

acceptEditsAllowlistbypassPermissionsContainerDenyEnvironment variable

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