pi-auto-mode

A pi package that re-implements the core of Claude Code's auto mode for pi.

It is modeled after lghupan/cc-automode:

• read-only tool allowlist fast path
• deterministic hard-deny checks for obviously unsafe actions
• two-stage classifier on every non-allowlisted tool call
• consecutive/total denial tracking
• auto-mode execution guidance injected into pi's system prompt
• denial history widget in the UI
• user override prompt on denials

What it does

When enabled, the extension intercepts tool calls in pi:

1. read, grep, find, and ls are allowed immediately by default.
   • this allowlist is also extended from local Claude Code project settings in:
     • .claude/settings.user.json
     • .claude/settings.json
   • the extension reads permissions.allow, permissions.allowedTools, allow, and allowedTools arrays when present
2. obvious hard-deny patterns are blocked immediately:
   • shell profile writes
   • cron creation
   • TLS verification weakening
   • destructive deletes outside the workspace
   • SSH key injection
   • auto-mode self-modification
3. everything else is classified with a two-stage LLM check:
   • stage 1: cheap YES / NO filter
   • stage 2: full JSON decision with reasoning only if stage 1 flags the action
4. if a denial happens in interactive mode, pi asks you whether to:
   • block
   • allow once
   • disable auto mode and allow

Install

From npm

Once published, the package can be installed from npm:

npm install pi-auto-mode

Directly from GitHub

You do not need to clone the repo first.

pi install git:github.com/r4vi/pi-auto-mode

You can also pin a ref:

pi install git:github.com/r4vi/pi-auto-mode@main
# or a tag / commit
pi install git:github.com/r4vi/pi-auto-mode@<tag-or-commit>

Raw GitHub URLs work too:

pi install https://github.com/r4vi/pi-auto-mode

As a local package

From the directory containing this package:

pi install ./pi-auto-mode

For one-off testing

pi -e ./pi-auto-mode/extensions/auto-mode.ts

Usage

Once loaded, auto mode is enabled by default.

Commands:

/auto-mode status
/auto-mode on
/auto-mode off
/auto-mode toggle
/auto-mode reset
/auto-mode reload
/auto-mode model
/auto-mode model github-copilot/gpt-5.4-mini

If no dedicated classifier model is configured, the extension prompts you to choose one when auto mode is enabled in interactive mode.

UI additions

• footer status for auto mode state
• recent denial history widget below the editor
• interactive override prompt when a denial happens

Configuration

Claude project allowlist interoperability

pi-auto-mode merges Claude Code tool allowlists from two places into its own fast-path allowlist:

Project-local files:

• .claude/settings.user.json
• .claude/settings.json

Global user files:

• ~/.claude/settings.user.json
• ~/.claude/settings.json

Supported fields:

• permissions.allow
• permissions.allowedTools
• allow
• allowedTools

Examples recognized:

{
  "permissions": {
    "allow": ["Bash(*)", "Read(*)", "Edit(src/**)"]
  }
}

Those entries are normalized to tool names for pi's allowlist fast path, so Bash(*) becomes bash, Read(*) becomes read, etc.

It does not walk parent directories. It only reads the current project directory plus the global ~/.claude directory.

You can inspect the merged result with:

/auto-mode status

Configuration

Create either of these in the target project:

• .pi/auto-mode.json
• auto-mode.json

Start from auto-mode.example.json.

Example:

{
  "enabled": true,
  "classifierModel": "github-copilot/gpt-5.4-mini",
  "failOpen": true,
  "maxConsecutiveDenials": 3,
  "maxTotalDenials": 20,
  "maxTranscriptLines": 60,
  "reasoningEffort": "high",
  "allowlistedTools": ["read", "grep", "find", "ls"],
  "environment": [
    "**Trusted repo**: this repository and its configured remotes",
    "**Trusted internal domains**: api.mycorp.internal, registry.mycorp.internal"
  ],
  "allowRules": [],
  "denyRules": []
}

Notes

• classifierModel is optional. If omitted, the extension uses the current active pi model.
• For a cheap GitHub Copilot-backed classifier, github-copilot/gpt-5.4-mini is a good default.
• The extension currently fails open by default, matching the reference repo's behavior when the classifier is unavailable.

Files

• package.json — pi package manifest
• extensions/auto-mode.ts — the extension
• auto-mode.example.json — starter config

Known gaps vs official Claude Code auto mode

This package mirrors the open-source reference architecture, not Anthropic's private implementation.

Current differences:

• no server-side prompt-injection probe
• no provider-side caching optimizations beyond what the selected model/provider already does
• JSON parsing is used for stage 2 instead of a dedicated classifier tool call
• policy is project-config based rather than Claude hook config based

Development

This package is intentionally dependency-light and relies on pi's extension runtime.