PI's extension model is built on packages. A package can contribute skills, extensions, prompt templates, themes, and tools. PiLot Studio gives you a UI for installing, inspecting, and disabling those resources without editing PI's configuration by hand.

Packages

Open Packages with the box icon or press 6. The panel has two tabs.

Installed

Each installed package shows its name, version, description, source, and the resource types it contributes:

extensions — PI extensions that hook into the agent lifecycle;
skills — reusable agent instructions;
prompts — prompt templates.

Actions:

Disable / Enable — keeps the package installed but stops all of its resources from loading.
Remove — runs pi remove <source>. Local filesystem packages cannot be removed by the package manager; delete them manually and refresh.
Open on npm — opens the package page when the source is an npm package.
Refresh — re-reads the installed list.

The list is read with pi list, so it matches the CLI. Disabled packages are stored in pi-agent.disabledPackages and survive a reload.

Available

The Available tab searches the npm registry for packages tagged with the pi-package keyword and shows their latest version and resource types. Install runs pi install npm:<name> and streams the package manager output into an overlay.

The marketplace list is a convenience, not a separate registry. A package that is not tagged pi-package will not appear in the tab, but you can still install it from the Command Palette with PiLot Studio: Install Resource and a source such as npm:my-package or a Git URL.

Updating

Update runs pi update and refreshes the installed list. The header also reports package updates and can run pi update --extensions. Package operations use the network, even when pi-agent.offline is on.

Light Mode disables package management and skips package discovery. The panel shows a banner while Light Mode is active.

Skills

Open Skills with the layers icon or press 7.

The panel lists every skill PI loaded for the current session, with:

its name and description,
a source badge: built-in, local, or package,
the source path or package name,
an expandable detail row with the full path,
Disable / Enable,
Remove package for package-provided skills.

A skill disabled here is stored in pi-agent.disabledSkills and stays installed. A skill from a disabled package cannot be enabled until the package is enabled.

The header has a discovery toggle. Turning it off starts no skills at all; the setting is pi-agent.disableSkillDiscovery. The search box filters by name and description.

Extra skill paths

At the bottom of the panel, Skill Paths adds local directories that contain SKILL.md files. Paths must be absolute and are stored in pi-agent.extraSkills. They are passed to PI as --skill values. Use this for a private skill collection that is not packaged.

Where skills come from

PI packages installed through the Packages tab.
Local skill directories configured with extraSkills.
PI's own discovery locations under the agent directory and trusted project .pi folders.
Built-in skills bundled with PI.

The exact set depends on your PI version and project trust. The panel's source badge and path are the authoritative answer for a given skill.

Tools and capabilities

Open Capabilities with the wrench icon or press 5.

The built-in tools are:

Tool	Purpose
`read`	Read files.
`bash`	Run shell commands.
`edit`	Make targeted replacements in files.
`write`	Create or overwrite files.
`grep`	Search file contents.
`find`	Find files by glob.
`ls`	List directories.

Presets

Preset	Behavior
`default`	All built-in tools enabled.
`review`	Read-only: `read`, `grep`, `find`, `ls`.
`none`	No tools. The agent can still reason about text you provide.
`custom`	Exactly the tools in `pi-agent.customTools`.

Changing a preset writes pi-agent.toolPreset. Toggling an individual tool switches the session to custom and stores the enabled names in pi-agent.customTools.

Custom tools

Add custom tool accepts a name of 1–32 characters: letters, numbers, -, or _, starting with a letter. Custom names are passed to PI alongside the built-ins, so a tool supplied by an extension or MCP server can be allowlisted explicitly.

Light Mode restricts the effective default preset to read, bash, edit, and write; an explicit review or custom preset keeps its own list.

System prompt

Open System Prompt with the terminal icon or press 8.

This tab shows the exact system prompt the model receives for the active session. It includes:

PI's built-in prompt,
SYSTEM.md if present,
APPEND_SYSTEM.md if present,
pi-agent.systemPrompt and pi-agent.appendSystemPrompts overrides,
per-run modifications made by extensions.

The view reports characters, lines, and an estimated token count. Copy copies the prompt; Wrap toggles line wrapping. The prompt refreshes when a new run starts or the session changes.

Editing the prompt files

Open Preferences → Configuration Files to create or edit:

SYSTEM.md — replaces PI's default system prompt for new sessions.
APPEND_SYSTEM.md — appends to the active prompt.

PiLot Studio creates the file in the agent directory if it is missing and opens it in an editor tab. Changes apply to new sessions. If pi-agent.systemPrompt or pi-agent.appendSystemPrompts is set, the panel warns that the files are being overridden until those settings are cleared.

Prompt templates

PI prompt templates are reusable prompts discovered from packages, project files, and extra paths. They appear in the composer's slash-command list under their own names. Selecting one expands it through PI, the same way the CLI does.

The Prompt Templates button in the composer opens a separate built-in library organized into analysis, implementation, quality, and workflow categories. It is a quick-start picker, not a list of PI package templates. You can search it and reuse recent entries.

To add your own template files, set pi-agent.extraPromptTemplates to their paths. To disable all template discovery, set pi-agent.disablePromptTemplateDiscovery.

Extensions

PI extensions are usually shipped inside packages. The Packages panel shows the extensions a package contributes and lets you disable the package as a whole. The Skills panel shows skills contributed by the same package.

For extension files outside a package, use pi-agent.extraExtensions. Each entry is passed as --extension and can point to a file or directory. pi-agent.disableExtensionDiscovery starts PI with --no-extensions; explicit extraExtensions paths still load.

Extensions can report status through PI's UI context. PiLot Studio forwards those statuses to the status line and the activity area, so long-running extension work is visible.

Relationship to PI's own settings

Everything in this section maps to a PI or pi-agent setting:

UI	Setting
Package disabled	`pi-agent.disabledPackages`
Skill disabled	`pi-agent.disabledSkills`
Extra skill paths	`pi-agent.extraSkills`
Tool preset	`pi-agent.toolPreset`
Custom tools	`pi-agent.customTools`
System prompt override	`pi-agent.systemPrompt`
Appended prompt	`pi-agent.appendSystemPrompts`
Extra extensions	`pi-agent.extraExtensions`
Extra prompt templates	`pi-agent.extraPromptTemplates`

The Settings reference lists the discovery toggles and their defaults.