@cassey@urbanists.social Some poking around turns up https://www.lend-engine.com/software-for-tool-libraries which has a free tier that may be enough for your needs?
Airtable might also be an option, if you don't have a ton of people you need to share it with (as it looks like the free plan is limited to 5 editors on a base) - I've used it for personal cataloging stuff and it's got a lot of flexibility. For ex, this is my sewing pattern base: https://airtable.com/appZIeYZt1O3d052B/shrJuMpvB64xrVkmF