Claude Code · L3 · 1
Claude Code · ISTO.

Lesson 3 · Skills, automations, GitHub

Before we start

Lesson 3: the data feed keeps the database up to date automatically.

01Lessons 1 and 2: the files Claude reads, then plan, phases, build, check, on the shared data.
02First half: work that repeats. How your build went, then skills and automations. Sage and Shopify: the scheduled jobs that could keep the database current, and where they would run.
03Second half: GitHub. Push a change, review it, and pull the approved version back.
The building blocks

The six building blocks of this course.

Lesson 1
VS Code tour
Files, Claude, terminal.
Memory and context
What Claude knows.
Lesson 2
Tools and reach
Scripts, connectors, data.
Plan, then build
One phase at a time.
Lesson 3We are here
Skills
Repeat a job.
Automations
Event or schedule.
Sharing through review
GitHub review.
Lesson 4
Your 4-minute demo
Show what you built.
Your Agentic Map
What, where, who, next.
All six blocks together

Without these blocks, you paste the context in and carry the answer out. They move that work into the project.

How the build went
Together · 8 min

Your first phase: how did it go?

  • Where you got to: which phase, and which step of the loop.
  • Where Claude went off track, and what you said to bring it back.
  • What you did twice: a step you'd rather not explain again.

The steps you did twice are where today's skills come from.

How the build went

Your build, step by step: where did it get hard?

Each story gets pinned to one step of the loop.

Skills · Automations · GitHub

Skills, automations and GitHub do different jobs.

Skills and automations help one person or a team. GitHub matters when work is shared or reviewed.

How automation starts

An automation starts when something happens, or when a time arrives.

Something happensAn event starts the job.
Event-triggered automationBefore a Sage export is loaded, check whether it was loaded already.
A time arrivesA schedule starts the job.
Scheduled automation · cronAt 07:00, look for a new Sage export and load it if there is one.

Next: a hook, a safety check inside Claude Code that runs before a named action.

Skills in Claude Code
Part 1 · Skills & automations

Every skill has a SKILL.md instruction file.

A global skill works in every project. A project skill works only here. Each can be just SKILL.md or a folder with material Claude needs.

Global skill · every projectInstructions you want everywhere: splitting a plan into phases, sketching before you build.
Project skill · this project onlyInstructions and, when useful, templates, references, images or scripts for this project.

One question decides: will I need a global skill in every project, or only here?

Skill · Live demo

Ask Claude to save a job you want to reuse as a skill; you check it before reuse.

Watch · 4 min

Make a global skill called project-status. When I ask for project status, tell me: what this project is for, what changed recently, what I should do next, and any risks or blockers. Do not change anything. Show me the file.

Use project-status.

1Claude creates the global skill folder and its SKILL.md file.
2Open it: a one-line description at the top, then the steps.
3Type / in the Claude panel: project-status is in the list.
4Run it: get the project’s purpose, recent work, next action and blockers.
What a skill can carry

A skill starts with SKILL.md and can carry useful files.

Instructions onlymy-skill/ └── SKILL.mdA small skill can be just its instruction file.
Instructions + supportmy-skill/ ├── SKILL.md ├── assets/ · images, templates ├── references/ · examples └── scripts/ · Python or other codeImages, templates and references give Claude reusable material. A script makes a repeated step exact and reliable.

Add supporting files when the job needs them; start with SKILL.md.

Skill · Habit: check a new skill

Before you trust a new skill, check one result against a known-good reference or expected outcome.

1Run the new skill once on real work.
2Choose your check: a stock figure, date or total; an approved template, source file or expected action.
3Compare. It matches: use the skill. It doesn't: fix the skill before you run it again.

A skill repeats its mistakes as faithfully as its good steps.

Hooks in Claude Code

A hook is a safety check that runs before Claude changes something.

You ask ClaudeFor example: change an original Sage export.
The hook checksIs this a file that must stay unchanged?
It stops or allowsThe original export is protected; a normal draft is allowed.

A hook is one kind of Claude Code automation. We will create this one, then test it.

Automation · Hook · Habit: protect original data

The original Sage export stays unchanged.

Watch · 4 min

Keep the original Sage exports in this project's data/raw folder unchanged so our stock and purchasing reports keep using the source data. If Claude tries to change one, however it tries or wherever I start the conversation, stop it and say: “Original exports stay unchanged. Make a correction note instead.” I still need to read and load the exports as usual. Show me what you set up in plain English.

Change order EC301 to CE301 in the original Sage purchase-orders export.

1Claude creates the hook and shows the small files behind it.
2Start a fresh Claude conversation, then ask it to change an original export.
3The hook stops the change and points to a safer next step.

Why: original exports are source evidence. Correct the result in a note, not in the source file.

Automation · Cron · Three Isto ideas ·

Three scheduled jobs Isto could use.

Discuss · 5 min
TIMESOURCE + JOBRESULT Weekdays · 07:00schedule starts New Sage exportvalidate + update database Shared databaseis current Weekdays · 08:00schedule starts Stock + purchase ordersmake an exceptions list Today’s listlow / late / due soon Mondays · 08:30schedule starts Sales, stock + ordersprepare for buying meeting Meeting packready to discuss

A schedule starts the job. It still needs an always-on service, a source for the data, and someone who owns the result.

Where it runs

An automated job needs a computer that stays on.

Your laptopThe job runs while the laptop is open. Close the lid and the scheduled work stops.
An always-on serviceA cloud service or rented computer that never sleeps. The job can run at 3 a.m. too.
Someone owns itWho pays, who keeps it working, and where its logins are kept safely: those are business decisions, not Claude’s.

Every few hours, a computer that stays on gets the latest Sage file and updates the shared database.

GitHub · one shared history
Part 2 · GitHub

GitHub keeps one shared project. A pull request holds each change for review.

GitHubshared cloud copy your projecta proposed change pull requestREVIEW GATE shared versionapproved copy PUSH MERGE PULL after merge your project · updated teammate's project

A teammate and you can share the approved version; a proposed change stays at the pull-request gate until it is reviewed and merged.

GitHub · one compact loop

One safe change: separate version → review → shared version.

Watch · 8 min

Make the dashboard background a pale yellow instead of white. Show me the result before you save it.

That looks good. Put the change on GitHub and open a pull request for a colleague to review. Do not merge it yet.

1Make one small change in a separate working version.
2Push it to GitHub and open the review.
3In this demo, you check the diff. In real work, a teammate approves and merges it.
4After the merge, pull brings the approved version back. Not shown today.

This is the whole loop once. You will practise it on your own project in Pre-L4.

To keep

Three ideas from today.

  • Check a new skill against a known-good reference or expected outcome before you trust it.
  • Automations start work without you: hooks react at a set moment; scheduled jobs run at a set time.
  • GitHub lets people review a change before it becomes part of the shared project.

Before lesson 4: your project on GitHub, one reviewed change, online behind a login, your 4-minute demo.

Your turn to ask

Questions?