When recruiting participants to take your survey or test, it's super important to give them a heads-up on what you are expecting before they take part. The more context they have before going in, the more likely you will get quality responses.
The purpose of the description field is to give you a chance to provide the information to participants so they can decide to take part and provide the answers you need.
What the description is used for:
Help participants decide whether to take your survey or test
Provide the full context they need to better answer questions and complete tasks
What to cover in your description to get the best out of your participant recruitment:
The aim of the study
What the participant will be required to do
Any sensitive information participants will have to provide
Anything you think the participant might be uncomfortable doing
Your contact details in case of questions.
Information on how the data will be used (publish a research study, guide UX direction or branding etc).
If you have ethics approval, the contact details of the ethics board in question
Depending on the content of your study, it can be useful to provide contact details of certain helplines. For example, if your study investigated drug abuse, providing respective helpline details can make sense. For more information about ethical standards, please refer to: http://www.apa.org/ethics/code/