I used to have a CLI that would trigger a Zapier webhook that would use [this CLI app](https://github.com/xavdid/zapier-igdb) to populate data into Airtable, but I actually moved the whole process to [Airtable Apps](https://airtable.com/marketplace) since I could customize the UI a little more. I've been meaning to open source it, but it's pretty customized so I'm not sure if it'd be widely useful.
I'm curious to see where you end up with this though! It's something I've put a lot of thought into.
There's not an API directly, but https://www.howlongtobeatsteam.com looks promising. It's got an API that you can use to cache your (or all) games. Zapier might be able to do it as well w/ this scraper: https://www.npmjs.com/package/howlongtobeat (disclosure, I work at Zapier).
I used to have a CLI that would trigger a Zapier webhook that would use [this CLI app](https://github.com/xavdid/zapier-igdb) to populate data into Airtable, but I actually moved the whole process to [Airtable Apps](https://airtable.com/marketplace) since I could customize the UI a little more. I've been meaning to open source it, but it's pretty customized so I'm not sure if it'd be widely useful.
I'm curious to see where you end up with this though! It's something I've put a lot of thought into.