create-gsd-extension

name	create-gsd-extension
description	Create, debug, and iterate on GSD extensions (TypeScript modules that add tools, commands, event hooks, custom UI, and providers to GSD). Use when asked to build an extension, add a tool the LLM can call, register a slash command, hook into GSD events, create custom TUI components, or modify GSD behavior. Triggers on "create extension", "build extension", "add a tool", "register command", "hook into gsd", "custom tool", "gsd plugin", "gsd extension".
tags	["gsd-2","skills","create-gsd-extension","debugging","typescript","llm"]

---|---------| | @mariozechner/pi-coding-agent | ExtensionAPI, ExtensionContext, Theme, event types, tool utilities, DynamicBorder, BorderedLoader, CustomEditor, highlightCode | | @sinclair/typebox | Type.Object, Type.String, Type.Number, Type.Optional, Type.Boolean, Type.Array | | @mariozechner/pi-ai | StringEnum (required for string enums), Type re-export | | @mariozechner/pi-tui | Text, Box, Container, Spacer, Markdown, SelectList, Input, matchesKey, Key, truncateToWidth, visibleWidth | | Node.js built-ins | node:fs, node:path, node:child_process, etc. |

</essential_principles>

Based on user intent, route to the appropriate workflow:

Building a new extension:

• "Create an extension", "build a tool", "I want to add a command" → workflows/create-extension.md

Adding capabilities to an existing extension:

• "Add a tool to my extension", "add event hook", "add custom rendering" → workflows/add-capability.md

Debugging an extension:

• "My extension doesn't work", "tool not showing up", "event not firing" → workflows/debug-extension.md

If user intent is clear from context, skip the question and go directly to the workflow.

<reference_index> All domain knowledge in references/:

Core architecture: extension-lifecycle.md, events-reference.md API surface: extensionapi-reference.md, extensioncontext-reference.md Capabilities: custom-tools.md, custom-commands.md, custom-ui.md, custom-rendering.md Patterns: state-management.md, system-prompt-modification.md, compaction-session-control.md Infrastructure: model-provider-management.md, remote-execution-overrides.md, packaging-distribution.md, mode-behavior.md Gotchas: key-rules-gotchas.md </reference_index>

<workflows_index>

Workflow	Purpose
create-extension.md	Build a new extension from scratch
add-capability.md	Add tools, commands, hooks, UI to an existing extension
debug-extension.md	Diagnose and fix extension issues
</workflows_index>

<success_criteria> Extension is complete when:

• TypeScript compiles without errors (jiti handles this at runtime)
• Extension loads on GSD startup or /reload without errors
• Tools appear in the LLM's system prompt and are callable
• Commands respond to /command input
• Event hooks fire at the expected lifecycle points
• Custom UI renders correctly within terminal width
• State persists correctly across session restarts (if stateful)
• Output is truncated to safe limits (if tools produce variable output) </success_criteria>