Jina.ai offer a really neat (currently free) API for this - you add https://r.jina.ai/ on the beginning of any API and it gives you back a Markdown version of the main content of that page, suitable for piping into an LLM.

Here's an example: https://r.jina.ai/https://simonwillison.net/2024/Sep/2/anato... - for this page: https://simonwillison.net/2024/Sep/2/anatomy-of-a-textual-us...

Their code is open source so you can run your own copy if you like: https://github.com/jina-ai/reader - it's written in TypeScript and uses Puppeteer and https://github.com/mozilla/readability

I've been using Readability (minus the Markdown) bit myself to extract the title and main content from a page - I have a recipe for running it via Playwright using my shot-scraper tool here: https://shot-scraper.datasette.io/en/stable/javascript.html#...

    shot-scraper javascript https://simonwillison.net/2024/Sep/2/anatomy-of-a-textual-user-interface/ "
    async () => {
      const readability = await import('https://cdn.skypack.dev/@mozilla/readability');
      return (new readability.Readability(document)).parse();
    }"