gh skill tutorial ​

The GitHub CLI ships a gh skill subcommand (v2.90+) that installs Agent Skills from any GitHub repository — not just Anthropic ones. gridgram's four skills (gg-install, gg-render, gg-icons, gg-author) use standards-only frontmatter, so the same bundle you see in the Claude marketplace also works in Copilot, Cursor, Gemini CLI, Codex, and Antigravity.

Time: ~5 minutes. Result: the gridgram skills installed into your agent of choice, plus the update command.

Prerequisites ​

Install these yourself:

• GitHub CLI (gh), v2.90 or later (earlier versions don't have the skill subcommand).
• A target agent host: Claude Code, GitHub Copilot, Cursor, Gemini CLI, Codex, or Antigravity. The --agent flag picks which.
• git (gh uses it under the hood).
• Network access to github.com.

Authenticate gh once if you haven't already:

gh auth status       # check
gh auth login        # if "not logged in"

Authentication isn't strictly required for a public repo like gridgram, but it avoids rate-limiting on repeated installs.

Check your gh skill availability:

gh skill --help

If you see "unknown command: skill", upgrade gh:

# Homebrew
brew upgrade gh

# Debian/Ubuntu
sudo apt install --only-upgrade gh

1. Pick your target agent ​

gh skill install --agent <target> supports six host targets. Each tutorial snippet from here on has a tab per target — pick yours and the commands copy-paste directly.

2. Preview before installing ​

gh skill preview downloads a SKILL.md and shows the frontmatter

• body so you can read what it'll do before letting it run:

gh skill preview ideamans/gridgram plugins/gridgram/skills/gg-install

Do the same for the other three (gg-render, gg-icons, gg-author) if you want to inspect each.

3. Install the skills ​

Install all four with one copy-paste. Switch tabs to match your target agent:

gh skill install ideamans/gridgram plugins/gridgram/skills/gg-install --agent claude-code
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-render  --agent claude-code
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-icons   --agent claude-code
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-author  --agent claude-code

gh skill install ideamans/gridgram plugins/gridgram/skills/gg-install --agent copilot
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-render  --agent copilot
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-icons   --agent copilot
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-author  --agent copilot

gh skill install ideamans/gridgram plugins/gridgram/skills/gg-install --agent cursor
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-render  --agent cursor
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-icons   --agent cursor
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-author  --agent cursor

gh skill install ideamans/gridgram plugins/gridgram/skills/gg-install --agent codex
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-render  --agent codex
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-icons   --agent codex
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-author  --agent codex

gh skill install ideamans/gridgram plugins/gridgram/skills/gg-install --agent gemini-cli
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-render  --agent gemini-cli
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-icons   --agent gemini-cli
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-author  --agent gemini-cli

gh skill install ideamans/gridgram plugins/gridgram/skills/gg-install --agent antigravity
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-render  --agent antigravity
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-icons   --agent antigravity
gh skill install ideamans/gridgram plugins/gridgram/skills/gg-author  --agent antigravity

Verify:

gh skill list

The list shows each skill plus the source repository + ref + tree SHA. That provenance metadata gets written directly into each SKILL.md's frontmatter on install, so gh skill update can detect content changes later even without a version bump.

4. Install the gg CLI ​

The skills shell out to the gg binary. Either path works:

Option A: Use /gg-install inside your agent ​

Restart your agent host so the new skills load, then ask:

Install the gridgram CLI for my platform.

The agent picks up /gg-install and performs:

1. OS + arch detection.
2. Download of the latest release from https://github.com/ideamans/gridgram/releases/latest.
3. Install into the first writable $PATH directory (or stage at /tmp/gg with a sudo hint).

Option B: Install gg the regular way ​

If you'd rather skip the skill, follow the standard install guide at Quick start (one-line curl / PowerShell scripts) or Install for manual alternatives. Any install that puts gg on $PATH is picked up by the skills automatically.

Verify ​

gg --help

You should see gg v<version>.

5. Try a first render ​

Draw a gridgram diagram showing a browser calling an API backed by a Postgres database. Save it as ~/first-diagram.svg.

The agent uses /gg-icons to pick icons, /gg-author to compose the .gg source, and /gg-render to produce the SVG with diagnostics. Open the result in a browser.

6. Keep everything up to date ​

Update skills ​

gh skill update

With no arguments it updates every installed skill. The provenance metadata in each SKILL.md tells gh where to fetch from — the tree SHA comparison means you'll get genuine content changes, not spurious no-op updates.

Update a single skill:

gh skill update ideamans/gridgram plugins/gridgram/skills/gg-author

Update the gg binary ​

Just ask the agent:

Update my gridgram CLI to the latest version.

/gg-install replaces the existing binary in place.

7. Uninstall (optional) ​

gh skill remove ideamans/gridgram plugins/gridgram/skills/gg-author
# …and the other three

To remove gg:

rm "$(which gg)"
rm -rf ~/.cache/gridgram

Troubleshooting ​

unknown command: skill ​

Upgrade gh to v2.90+. Check with gh --version.

"Rate limit exceeded" from gh skill install ​

Run gh auth login and retry — authenticated requests get a higher rate limit.

Skill installed but agent doesn't see it ​

Restart the agent host. Most hosts only scan the skills directory at startup.

Skill with extra frontmatter fields logs a warning ​

Expected: Claude Code's frontmatter extensions (disable-model-invocation, paths, …) aren't in gridgram's SKILL files, so this shouldn't happen. If it does, file an issue.

Where next ​

• Claude Code plugin tutorial — slash-command-driven flow for Claude Code users, with marketplace-level auto-update.
• CLI reference — what the skills are doing under the hood.
• context7 — complementary MCP retrieval; works alongside any skill host.