How to Build Your First Custom OpenClaw Skill — A Complete Beginner's Guide

If no existing skill does exactly what you need, you can build one. Here is how to create a working custom skill in under 30 minutes — no prior programming experience required.

OpenClaw's 13,700+ ClawHub skills cover an enormous range of use cases. But the best AI agent is one tailored to your specific workflow — and that means eventually building something that does not exist yet. The good news: building a skill is simpler than it sounds. If you can follow instructions and type basic commands, you can build a working skill.

What a Skill Is Made Of

Every skill is a directory containing two things: a SKILL.md file that tells the LLM what the skill does and when to use it, and a scripts/ folder containing the code that actually runs. The SKILL.md is the brain — the AI reads it to understand the skill's purpose. The scripts are the muscles — they execute when the skill is invoked.

Building a Website Checker Skill

We will build a skill that checks whether a website is online and returns its response time. This is a useful, practical skill that clearly demonstrates the pattern.

First, create the skill directory:

mkdir -p ~/.openclaw/skills/website-checker/scripts

Create the script at ~/.openclaw/skills/website-checker/scripts/check.sh:

#!/bin/bash
URL=$1
RESULT=$(curl -o /dev/null -s -w "%{http_code} %{time_total}" "$URL")
HTTP_CODE=$(echo $RESULT | cut -d' ' -f1)
TIME=$(echo $RESULT | cut -d' ' -f2)
if [ "$HTTP_CODE" = "200" ]; then
  echo "✅ $URL is online. Response time: ${TIME}s"
else
  echo "❌ $URL returned HTTP $HTTP_CODE — may be down."
fi

Make it executable: chmod +x ~/.openclaw/skills/website-checker/scripts/check.sh

Create the SKILL.md at ~/.openclaw/skills/website-checker/SKILL.md:

---
name: website-checker
description: Check whether a website is online and return its response time
version: 1.0.0
tags: [monitoring, web]
dependencies: [curl]
---

Use this skill when the user asks if a website is online, reachable or working.
Also use for response time checks or uptime verification.

Instructions: Run scripts/check.sh [URL] and report the result to the user.

Install it: openclaw skills install --local website-checker

Test it by sending your agent: "Check if google.com is online." It should respond with the status and response time.