Will it be an open directory? By open I mean can website visitors search for the tools? The wording on the website sounds like you collect requirements, do a (manual) search ("We do a thorough search of our database and the internet") and contact (email?) the user with results. That would make you a middleman, possibly taking a referral bonus.

I use directories like https://aws.amazon.com/marketplace/ https://elements.heroku.com/addons https://github.com/marketplace