install-extension

install-extension is a skill for Claude Code from sbusso/claudeclaw. It costs 18 tokens per session (552 once invoked), scanned A, original, MIT.

An installer for ClaudeClaw extensions, which add functions such as Slack support or triage workflows to a ClaudeClaw project. It fetches an extension from GitHub, installs its dependencies, compiles it, and runs any setup script it provides.

In plain words
What is it for?
Use it to install a named extension such as slack or triage, while checking whether it is already installed and reading its manifest first.
Why use it?
It removes the repeated manual work of finding an extension, copying it into the project, installing packages, and compiling it.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: positional $N argument.

Part of the claudeclaw plugin — 27 skills shipped together

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/sbusso/claudeclaw/install-extension
Any agent
npx skills add sbusso/claudeclaw --skill install-extension
Clone the repo
git clone --depth 1 https://github.com/sbusso/claudeclaw

Made for: Claude Code.

Or install claudeclaw, the plugin that ships this one along with the rest of its 27 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for install-extension

README.md
[![agentmods](https://agentmods.dev/badge/skills/sbusso/claudeclaw/install-extension.svg)](https://agentmods.dev/skills/sbusso/claudeclaw/install-extension)
Your own site
<a href="https://agentmods.dev/skills/sbusso/claudeclaw/install-extension"><img src="https://agentmods.dev/badge/skills/sbusso/claudeclaw/install-extension.svg" alt="Measured on agentmods" height="20"></a>
Per session 18 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 552 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00018 $0.00552
Opus 5 $0.00009 $0.00276
Sonnet 5 $0.00004 $0.00110
Haiku 4.5 $0.00002 $0.00055

Measured 6d ago against content hash 4513eb045cb1, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

install-extension scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 6d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/install-extension/SKILL.md · 104 lines

What it actually says

Install Extension

Install a ClaudeClaw extension from GitHub.

Usage

/install slack
/install triage

Flow

1. Validate input

The argument is the extension short name (e.g., slack, triage). The full repo name is claudeclaw-<name>.

EXTENSION_NAME="${1}"
REPO="https://github.com/sbusso/claudeclaw-${EXTENSION_NAME}.git"
EXT_DIR="extensions/claudeclaw-${EXTENSION_NAME}"

2. Check if already installed

[ -d "$EXT_DIR" ] && echo "Extension claudeclaw-${EXTENSION_NAME} is already installed." && exit 0

If already installed, ask if the user wants to update instead (git pull + rebuild).

3. Clone the extension

mkdir -p extensions
git clone "$REPO" "$EXT_DIR"

4. Read manifest and install dependencies

cat "$EXT_DIR/manifest.json"

If manifest.json has a dependencies field, install them at the root:

cd "$(git rev-parse --show-toplevel)" && npm install <each dependency with version>

5. Compile the extension

cd "$EXT_DIR" && npx tsc

6. Run post-install hook

If manifest.json has hooks.postInstall:

chmod +x "$EXT_DIR/hooks/install.sh"
bash "$EXT_DIR/hooks/install.sh" "$(git rev-parse --show-toplevel)"

This copies skills, agents, and agent skills into the ClaudeClaw root.

7. Rebuild core

npm run build

8. Restart service

Detect OS and restart:

macOS:

SERVICE_NAME=$(launchctl list | grep claudeclaw | awk '{print $3}')
[ -n "$SERVICE_NAME" ] && launchctl kickstart -k "gui/$(id -u)/$SERVICE_NAME"

Linux:

systemctl --user restart claudeclaw

9. Verify

Print confirmation:

Extension claudeclaw-<name> installed successfully.
- Skills: <list from manifest>
- Type: <channel|extension>
- Restart: service restarted
Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 6d ago First seen · 104 lines · 18 tokens per session scan A 4513eb045cb1

Subscribe to this mod's changes

install-extension is a skill published in the GitHub repository sbusso/claudeclaw (193 stars, last pushed 24d ago), licensed MIT. It adds 18 tokens to every session and 552 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.