Session Agent Selector Extension for pi

A shareable pi package that lets you select a local agent markdown file and apply it as the active profile for the current session.

What it does

It adapts agent files into session profiles:

• model → applied to the current session when available
• thinking → applied to the current session
• tools → applied automatically when present
• markdown body → injected as an overlay into the system prompt for future turns

This extension does not run the selected file as a real sub-agent and does not replace pi's base system prompt.

Supported directories

• ~/.pi/agent/agents/
• ~/.pi/agents/

Discovery safety rules

• only regular .md files are loaded
• symlinked files are rejected
• files larger than 100 KB are rejected

Supported frontmatter

---
description: Security Code Reviewer
model: openrouter/openai/gpt-5.4
thinking: high
tools: read, bash, edit, write, grep, find, ls
---

Example agent profile

---
description: Security Code Reviewer
model: openrouter/openai/gpt-5.4
thinking: high
tools: read, bash, grep, find, ls
---

You are a security auditor. Review code for vulnerabilities and provide clear remediation advice.

Supported fields:

• description
• model
• thinking
• tools

Ignored fields:

• prompt_mode
• max_turns
• any unknown frontmatter fields

Commands

• /agent → open the agent picker
• /agent <name> → activate an agent by name when unambiguous
• /agent clear → clear the active profile overlay
• /agent show → show active profile metadata and a short preview

Example usage

/agent
/agent auditor
/agent show
/agent clear

Important behavior

Clear semantics

/agent clear removes the active profile overlay and status indicator.

It restores the previous model and thinking level only if they are still using the agent-applied values at clear time. If you manually changed model or thinking after activating the agent, your newer values are preserved.

Tool selection is not automatically restored.

Duplicate names

If multiple files share the same name, /agent <name> will fail clearly and ask you to use /agent to pick the intended profile.

Discovery freshness

The extension re-scans the supported directories on every /agent invocation, so added or removed files are picked up without file watching.

Discovery trust boundary

The extension intentionally rejects symlinked agent files and oversized files. This keeps profile discovery constrained to regular markdown files that physically live in the approved directories.

Install

Prerequisites

• pi installed and working
• Node.js 20.6+ if you are developing or installing from a local checkout

Use as a local package during development

npm install
pi install /absolute/path/to/pi-agent-selector

You can also try it without installing:

pi -e /absolute/path/to/pi-agent-selector

Use as a published pi package

Once published to npm or a git repository, install it with pi package sources such as:

pi install npm:pi-agent-selector@0.1.0
# or
pi install git:github.com/kevinvargasl/pi-agent-selector@v0.1.0

Add it directly to ~/.pi/agent/settings.json

You can also register it as a package source in your global pi settings:

{
  "packages": [
    "npm:pi-agent-selector@0.1.0"
  ]
}

Or from git:

{
  "packages": [
    "git:github.com/kevinvargasl/pi-agent-selector@v0.1.0"
  ]
}

Troubleshooting

• If a model from an agent file does not activate, make sure the model field uses pi's exact provider/model identifier.
• If you use a proxy or alternate provider, specify that provider explicitly in the agent file.
• If VS Code reports missing Node or pi package types while developing, run npm install in the repo root.

Package entry

This repo is structured as a shareable pi package.

The extension entry point is:

• src/index.ts

Configured in package.json under:

{
  "pi": {
    "extensions": ["./src/index.ts"]
  }
}

Release notes

See CHANGELOG.md for package version history.