Permission Rules: Syntax & Wildcards

While modes set the baseline, rules allow you to fine-tune exactly what Claude can and cannot do.

Basic Syntax

Rules follow the format Tool or Tool(specifier).

Example	Matches
Bash	All Bash commands
Bash(npm run build)	Exactly that command
Read(./.env)	Reads the local .env file
WebFetch(domain:example.com)	Web fetches for that domain

Wildcards

* can match one or more tokens.

• Bash(npm run *): Matches any npm run command.
• Bash(git * main): Matches git checkout main, git merge main, etc.
• Bash(ls*): Matches ls, lsof, and ls -la.

Word Boundaries

Bash(ls *) vs Bash(ls*):

• Bash(ls *) matches ls -la (note the space), but not lsof.
• Bash(ls*) matches both.

Note: For Bash rules, Claude automatically strips process wrappers like timeout, nice, and nohup before matching.