Skills

Skill 21 of 54

Messages

Add new safe-output message types and wire validation/rendering.

2 minutes · 497 words · 14 sections

Install

$ npx skills add github/gh-aw --skill messages

$ npx skills add github/gh-aw

The first command installs just this skill, by the name in its SKILL.md; the second installs the whole repository.

Adding New Message Types Guide

Messages · github/gh-aw · Skills Docs

{
	"messages": {
		"properties": {
		  "my-new-message": {
		    "type": "string",
		    "description": "Description of when this message is used. Available placeholders: {placeholder1}, {placeholder2}.",
		    "examples": [
		      "Example message with {placeholder1}"
		    ]
		  }
		}
	}
}

// @ts-check
/// <reference types="@actions/github-script" />

const { getMessages, renderTemplate, toSnakeCase } = require("./messages_core.cjs");

/**
 * @typedef {Object} MyNewMessageContext
 * @property {string} placeholder1 - Description of placeholder1
 * @property {string} placeholder2 - Description of placeholder2
 */

function getMyNewMessage(ctx) {
	const messages = getMessages();
	const templateContext = toSnakeCase(ctx);
	const defaultMessage = "Default message with {placeholder1} and {placeholder2}";

	return messages?.myNewMessage
		? renderTemplate(messages.myNewMessage, templateContext)
		: renderTemplate(defaultMessage, templateContext);
}

module.exports = {
	getMyNewMessage,
};

import { describe, it, expect, beforeEach, vi } from "vitest";

const mockCore = { warning: vi.fn() };
global.core = mockCore;

describe("getMyNewMessage", () => {
	beforeEach(() => {
		vi.clearAllMocks();
		delete process.env.GH_AW_SAFE_OUTPUT_MESSAGES;
	});

	it("returns the default message when no custom template is configured", async () => {
		const { getMyNewMessage } = await import("./messages_my_new.cjs");
		const result = getMyNewMessage({ placeholder1: "value1", placeholder2: "value2" });
		expect(result).toBe("Default message with value1 and value2");
	});

	it("uses the custom template when configured", async () => {
		process.env.GH_AW_SAFE_OUTPUT_MESSAGES = JSON.stringify({ myNewMessage: "Custom: {placeholder1}" });
		const { getMyNewMessage } = await import("./messages_my_new.cjs");
		const result = getMyNewMessage({ placeholder1: "test", placeholder2: "ignored" });
		expect(result).toContain("Custom: test");
	});
});

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How this issue was made

Source

github.com/github/gh-aw, branch main, last pushed 24 September 2026.

Licence

MIT — the text of every skill is reproduced unmodified, frontmatter included, under the upstream licence.

Discovery

54 skills found by walking the repository tree for SKILL.md, not by matching a directory convention. 4 distinct layouts observed: .claude/skills/*/SKILL.md, .github/skills/*/SKILL.md, .squad/*/skill.md, SKILL.md (repo root).

Authorship

27 of 54 skills are installed into the repository rather than published from it. They are shelved in the closing “Credited skills” part and remain the work of their own authors. A skill counts as credited when its only copy lives under one agent’s dot directory; visible directories, per-agent mirror sets, and skills installable from this repository on skills.sh all count as published.

Issue colours

Resolved from a curated brand profile — hue 295°, chroma 0.190. Two accent tones are generated per issue and each is proven against its own ground before it ships: a single accent that passes AA on both light and dark paper is arithmetically impossible.

Heading repairs

1 repair applied to this skill so the document has one h1 and no skipped levels:

Shifted “14 headings” from h1 to h2 so the skill title is the only h1.

Spec compliance

4 editorial notes across 3 of 54 skills. They are printed in the margin of each skill rather than as errors here.

Images

Images inside a skill come from the upstream repository. Where the author gave no alternative text we mark the image decorative rather than inventing a description — a plausible caption we made up is worse than none for the reader who depends on it.

Signal

Install counts come from skills.sh. They measure downloads, not quality, and an unranked repository is not an unread one.

Agent surfaces

The whole issue is available as one markdown document at /github/gh-aw.md, and each skill at its own .md URL.

Publication

Set by Skills Docs from the source repository. Body text is Literata at the reader’s chosen size and measure; code is Geist Mono. Nothing on this page was written by us except this paragraph.

Messages

Adding New Message Types Guide

Messages

Adding New Message Types Guide

Overview

Step 1: Update JSON Schema

Step 2: Update Go Struct

Step 3: Update the parser if needed

Step 4: Create the JavaScript message module

Step 5: Add tests

Step 6: Update the core JS type metadata and exports

Step 7: Wire it into the real build path

Step 8: Use the message in consumer scripts

Step 9: Update documentation

Verification Checklist

References

Notes

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