create-gsd-extension

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".

Quality

82%

Does it follow best practices?

Run evals on this skill

Adds up to 20 points to the overall score

View guide

Securityby

Passed

No findings from the security scan

Quality

Content

65%

Reviews the quality of instructions and guidance provided to agents. Good implementation is clear, handles edge cases, and produces reliable results.

The body is lean, well-organized, and packed with concrete rules, but its actionability and workflow clarity are undermined because the workflow and docs files it routes to are missing from the bundle, and there is no in-line executable extension skeleton. Progressive disclosure is partially broken by the same missing references.

Suggestions

Add the missing `workflows/create-extension.md`, `add-capability.md`, and `debug-extension.md` files (or inline minimal step-by-step build/debug procedures) so the routing targets resolve.

Include a copy-paste-ready minimal extension skeleton (default export, `ExtensionAPI` wiring, one tool and one command registration) directly in the body to lift actionability to the top anchor.

Either provide the referenced `docs/extension-sdk/manifest-spec.md`, `testing.md`, and `docs/extension-sdk/` files or remove those entries from the reference_index so all navigation links resolve.

Dimension	Reasoning	Score
Conciseness	Dense, token-efficient bullet lists and tables with no concept-explanation padding (no 'what is TypeScript/an extension' filler); every line states a concrete rule or import, matching the 'lean and efficient; every token earns its place' anchor.	3 / 3
Actionability	Concrete directives exist ("Use `StringEnum` from `@gsd/pi-ai`", "Truncate tool output to 50KB / 2000 lines", "Use `pi.exec()` not `child_process`"), but there are no executable code examples or an extension skeleton, and the detailed build steps live in `workflows/create-extension.md` which is not present in the bundle.	2 / 3
Workflow Clarity	Routing maps intents to workflows and `success_criteria` provides a solid validation checklist (compiles, loads on `/reload`, tools appear in system prompt), but the core build/debug sequences are deferred to `workflows/*.md` files that do not exist, leaving the main multi-step sequence absent from the bundle.	2 / 3
Progressive Disclosure	Section organization and one-level-deep signaling are good, but routing points to `workflows/create-extension.md`, `add-capability.md`, and `debug-extension.md` and the reference_index cites `docs/extension-sdk/manifest-spec.md`, `testing.md`, and `docs/extension-sdk/` — none of which exist in the bundle, so a large share of the navigation is dead links rather than resolvable one-level-deep references.	2 / 3
	Total	9 / 12 Passed

Description

100%

Based on the skill's description, can an agent find and select it at the right time? Clear, specific descriptions lead to better discovery.

The description is excellent: third-person voice, concrete capabilities, explicit 'Use when...' guidance, and a rich set of natural trigger terms scoped to a clear niche. All four dimensions hit the top anchor.

Dimension	Reasoning	Score
Specificity	Names multiple concrete actions — "Create, debug, and iterate on GSD extensions" plus "add tools, commands, event hooks, custom UI, and providers" — matching the 'lists multiple specific concrete actions' anchor.	3 / 3
Completeness	Clearly answers both what (create/debug/iterate GSD extensions, the listed capabilities) and when ("Use when asked to build an extension..." plus the explicit trigger list), satisfying the both-what-and-when anchor.	3 / 3
Trigger Term Quality	Explicit natural-language triggers ("create extension", "build extension", "add a tool", "register command", "hook into gsd", "custom tool", "gsd plugin", "gsd extension") give good coverage of phrases users would actually say.	3 / 3
Distinctiveness Conflict Risk	Scoped tightly to GSD extensions with niche-specific triggers ("gsd plugin", "gsd extension", "hook into gsd"), making it unlikely to fire for unrelated skills.	3 / 3
	Total	12 / 12 Passed

Validation

100%

Warnings & errors only

Checks the skill against the spec for correct structure and formatting. All validation checks must pass before discovery and implementation can be scored.

Validation — 16 / 16 Passed

Validation for skill structure

No warnings or errors.

Repository: gsd-build/gsd-2
Path: src/resources/skills/create-gsd-extension/SKILL.md
Commit: 33c00aa

Reviewed: about 14 hours ago

Table of Contents

Discovery Implementation Validation

Is this your skill?

If you maintain this skill, you can claim it as your own. Once claimed, you can manage eval scenarios, bundle related skills, attach documentation or rules, and ensure cross-agent compatibility.