pi-permissions

A pi extension that provides configurable allow/deny permission rules for tool calls — control which bash commands, file reads, writes, and edits the agent can perform.

• Define allow rules to whitelist specific commands
• Define deny rules to block dangerous operations
• Deny always wins — block git push even if git * is allowed
• Supports glob patterns with * wildcards
• Project-local or global configuration

Install

pi install npm:pi-permissions

Alternative install methods

From the public git repo:

pi install git:github.com/NicoAvanzDev/pi-permissions

From a local clone:

pi install .

Load without installing:

pi --no-extensions -e npm:pi-permissions

Quick start

Create .pi/permissions.json in your project (or ~/.pi/agent/permissions.json for global rules):

{
  "permissions": {
    "allow": [
      "Bash(npm run *)",
      "Bash(npm test *)",
      "Bash(git commit *)",
      "Bash(git diff *)",
      "Bash(git status)",
      "Bash(git log *)"
    ],
    "deny": [
      "Bash(git push *)",
      "Bash(rm -rf *)",
      "Write(*.env)",
      "Edit(*.env)"
    ]
  }
}

On session start, the extension loads your rules and reports how many were found. Any tool call that matches a deny rule is blocked before execution.

Example session

> pi
Permissions loaded: 6 allow, 4 deny rules

> (agent tries to run `git push origin main`)
⛔ Blocked: Bash command matches deny rule "Bash(git push *)"

After editing permissions.json, type /reload in pi to apply the changes.

How it works

Rule format

Rules use the format Tool(pattern) where:

• Tool — the pi tool name: Bash, Write, Edit, Read
• pattern — a glob pattern where * matches any characters

Supported tools

Tool	What the pattern matches against
Bash(pattern)	The bash command string
Write(pattern)	The file path being written
Edit(pattern)	The file path being edited
Read(pattern)	The file path being read

Evaluation logic

For every tool call the extension:

1. checks deny rules first — if any deny rule matches, the call is blocked
2. checks allow rules next — if allow rules exist for that tool, the call must match at least one
3. passes through — if no allow rules exist for the tool, all calls are permitted (unless denied)

This means:

• Use deny to block specific dangerous commands
• Use allow to whitelist only approved commands (everything else is blocked)
• Deny always wins over allow

Pattern examples

Pattern	Matches	Doesn't match
Bash(git push *)	git push origin main	git pull
Bash(npm run *)	npm run build, npm run test	npm install
Bash(* --version)	node --version, npm --version	node index.js
Write(*.env)	.env, app.env	.env.example
Write(secrets/*)	secrets/key.pem	src/secrets.ts

Configuration

Location	Scope
.pi/permissions.json	Project-local (checked first)
~/.pi/agent/permissions.json	Global fallback

The extension checks the project-local path first. If not found, it falls back to the global config.

Notes

• rules are loaded once on session start
• use /reload to pick up changes without restarting
• deny rules are always evaluated before allow rules
• if no allow rules exist for a tool type, all calls for that tool are permitted
• glob * matches any sequence of characters (including path separators in file patterns)

License

MIT