Some link only answers can be okay if they are specifically telling us what exactly is at the link and showing why it cannot be copied. While we prefer a step by step solution here there isn't really a problem if there is a real reason the answer is a link.
For this reason I would apply the same reasoning and quality requirements we have as I would an answer that is recommending software:
Follow this general outline:
BOLD items are required.
- Title of the product with a link to the download/main page.
- Quote the site's product summary.
- Add any pictures that are relevant to the question.
- If it's not installed using a normal installation file, or package manager, then give instructions on how to install.
- Give a brief overview of HOW to use the product OR in cases where it's too long, link to the product's manual pages.
- Give any personalized information to the OP regarding how the recommendation solves his/her question.
- Specify any system requirements, e.g. Only works on Windows, Linux, OSX, or bootable media.
Things NOT to DO:
- Post only a link to the site.
- Recommend software that you haven't used personally (there MAY be rare occasions where this is valid, BUT you must let the OP know this).
- Answer questions that are simply asking "What's the best XX software" or "I need something that does XX."
