blog-to-newsletter-action

When you merge a pull request that adds a post to your blog, this GitHub Action kicks in: it reads the post, generates a polished newsletter draft using an AI third party (Claude), creates it in your email automation (Mailchimp), and sends you a message (Telegram) to review and approve before anything goes out.

Note

This action currently supports Mailchimp for newsletters, Claude for content generation, and Telegram for approval. All three are designed to be swappable — the architecture is provider-based and can be extended to support other services.

How it works

PR merged on GitHub
  → GitHub Action detects new blog post
  → Claude generates HTML + plain text newsletter
  → Mailchimp draft campaign created
  → Telegram message sent with preview and buttons:
     - [📧 Send Test Email] (optional)
     - [🗑 Discard]
     - [✅ Approve & Send]
  → You tap Approve → newsletter sent to your subscribers ✓

The approval step is handled by a separate worker: blog-to-newsletter-worker. You'll need to deploy it too.

Requirements

Before setting up this action you'll need:

• A Mailchimp account with an audience
• An Anthropic API key
• A Telegram bot (see setup below)
• The blog-to-newsletter-worker deployed

Setup

The action relies on external services, here's a summary of how to get each one ready.

Mailchimp

1. Log in to Mailchimp
2. Go to Account → Extras → API keys and create an API key
3. Go to Audience → Settings → Audience name and defaults and copy the Audience ID

Telegram

1. Open Telegram and message @BotFather
2. Send /newbot and follow the prompts → you get a bot token
3. Start a conversation with your new bot
4. Message @userinfobot to get your chat ID

Worker

Fork and deploy blog-to-newsletter-worker. Follow its README to set secrets and register the Telegram webhook.

Usage

The action works best when triggered on push to main with a path filter targeting your blog posts directory — so it only runs when a new post is actually merged, not on every push.

Add the following workflow to your repository at .github/workflows/newsletter.yml:

name: Newsletter

on:
  push:
    branches: [main]

jobs:
  newsletter:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
        with:
          persist-credentials: false

      - uses: peterpeterparker/blog-to-newsletter-action@01db4d6f3e0d586101c04806522e0c24c371ed9f # v0.0.6
        with:
          blog_posts_path: "src/blog"
          blog_base_url: "https://website.com"
          blog_author: "John"
          github_token: ${{ secrets.GITHUB_TOKEN }}
          mailchimp_api_key: ${{ secrets.MAILCHIMP_API_KEY }}
          mailchimp_list_id: "your-list-id"
          mailchimp_reply_to: "you@example.com"
          anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}
          telegram_bot_token: ${{ secrets.TELEGRAM_BOT_TOKEN }}
          telegram_chat_id: ${{ secrets.TELEGRAM_CHAT_ID }}

Note

If multiple blog posts are merged in a single pull request, the action will generate a single newsletter covering all of them.

Inputs

Blog

Input	Required	Default	Description
blog_posts_path	✅	—	Path to your blog posts directory (e.g. src/blog)
blog_base_url	✅	—	Base URL of your blog (e.g. https://website.com)
blog_author	✅	—	Author name — used to write the newsletter in first person
blog_audience		developer	Target audience (e.g. developer, designer, entrepreneur)

Note

Both author and audience are used in the prompt generation.

Mailchimp

Input	Required	Default	Description
mailchimp_api_key	✅	—	Mailchimp API key
mailchimp_list_id	✅	—	Mailchimp audience/list ID
mailchimp_reply_to	✅	—	Reply-to email address
mailchimp_from_name		blog_author	Sender display name. Defaults to blog_author if not set
mailchimp_test_emails		—	Comma-separated emails for test sends. If set, adds a [📧 Send Test Email] button to the Telegram message

Anthropic

Input	Required	Default	Description
anthropic_api_key	✅	—	Anthropic API key
anthropic_model		claude-sonnet-4-6	Claude model to use
anthropic_max_tokens		10000	Max tokens for the generated newsletter

Telegram

Input	Required	Default	Description
telegram_bot_token	✅	—	Telegram bot token from @BotFather
telegram_chat_id	✅	—	Your Telegram chat ID

Other

Input	Required	Default	Description
github_token		—	Optional GitHub token for fetching commit info from the GitHub API. Useful for private repos or to avoid rate limits

Secrets

Add these to your repository under Settings → Secrets → Actions:

Secret	Description
ANTHROPIC_API_KEY	Your Anthropic API key
MAILCHIMP_API_KEY	Your Mailchimp API key
TELEGRAM_BOT_TOKEN	Your Telegram bot token
TELEGRAM_CHAT_ID	Your Telegram chat ID

Tip

mailchimp_list_id, mailchimp_reply_to, blog_base_url, and blog_author are not sensitive — you can provide them directly in your workflow file.

License

MIT