01
It starts by itself
email code changed. Runs in GitHub Actions or Claude Code routine.
- ↻ email code changed
push touching src/backend/main.mo or src/frontend/**
caffeinelabs · 28K installsExtension Email Marketing skill
Runs by itself, email code changed.
Every marketing mail can unsubscribe.
Install the Extension Email Marketing skill and make it a habit: follow https://gethabit.dev/skills/caffeinelabs/extension-email-marketing.md
- 1Copy
- 2Paste into Claude Code, Codex or Cursor
- 3It runs by itself
28K installs2 starsApache-2.0 licenceSource on GitHub ↗
Extension Email Marketing
by caffeinelabs · 28K installs
The skill
The extension email marketing skill helps Caffeine AI app builders add marketing email to subscribers, with topics, email verification and a working unsubscribe page.
Only when you ask.
The habit
Every marketing mail can unsubscribe.
↻ Runs by itselfemail code changed
How the habit works.
You don't have to.
When does it start? How does it check its work? What does it remember?
One run, step by step.
Then it stops.
Stops after one pass over the six setup steps per run, with at most one retry.
- 01
Read the log
The agent reads which setup steps failed in the last run.
- 02
Check dependencies
It confirms the mops packages and the @caffeineai/email-marketing npm package are installed.
- 03
Check backend state
It looks for the stable fields emailSubscribers and unsubscribeTokens plus the verification states in the migration chain head.
- 04
Check sending
It confirms mail goes through EmailMarketing.sendMarketingEmail or sendMarketingEmailTo and the body carries {{UNSUBSCRIBE_URL}}.
- 05
Check unsubscribe page
It confirms the /unsubscribe route is public and uses the useUnsubscribe hook with a button.
- 06
Check verification skill
It also runs the checks of extension-email-verification, which this skill depends on.
- 07
Log and report
It writes each step as pass or fail to the run log and notifies you on a fail.
What it may do.
Nothing more.
It writes only in its own folder and asks you before anything goes out.
- Writes only inloops/email-unsubscribe-check-loop/**
- Talks tono outside service
- Sendsnothing
- Your OKNothing goes out, so it needs no OK.
Is it for you?
Use it when it fits.
Read both lists. If the left one sounds like you, the Extension Email Marketing skill helps.
Use it when
- ✓ You build a Caffeine app that sends newsletters
- ✓ You need topic-based subscriber lists
- ✓ You upgrade from an older email-marketing version
Skip it when
- – Your app is not built on Caffeine AI
- – You only send transactional mail
Extension Email Marketing skill, answered.
Does this loop send marketing mail?
No. It only checks that the code which sends mail is set up the way the skill requires.
Why check the /unsubscribe route so closely?
The skill says a missing route leaves recipients on a page that does not exist, which it calls a compliance failure.
How do I install the Extension Email Marketing skill?
Copy the prompt at the top into your agent. It installs the skill from caffeinelabs/skills and sets up the habit. Or run npx skills add caffeinelabs/skills --skill extension-email-marketing.
Is the Extension Email Marketing skill free?
Yes. It is published under Apache-2.0. Habit is free too.
Extension Email Marketing. Now as a habit.
Install the Extension Email Marketing skill and make it a habit: follow https://gethabit.dev/skills/caffeinelabs/extension-email-marketing.md
All caffeinelabs skills →More code skills →
Works in
- Claude Code
- Codex
- Cursor
- ChatGPT
- Claude app
Made by caffeinelabs, published under Apache-2.0. Habit links to the original and never changes it. Is this your skill?