Our current practice is to include the tool as long as there's at least 1 sentence describing it and 1 image displaying it. We also include a "Level of detail" number with each listing.

Some tools have entire websites and detailed plans describing them, whereas some just have the minimal 1 sentence and 1 image. The decision we had to make was "Is it worthwhile including tools with just 1 image and 1 sentence?". The consensus was that it's better to include them than to exclude them. Sometimes the minimal description and image is enough to reproduce the tool, or to provide "idea value" to a potential builder.

You are not the first person to wonder about this! We might want to add details on this to our About Us page.

In some situations, a gentle prod to the tool builder will result in some additional details or plans.