In the agile Scrum world, instead of providing complete, detailed descriptions of how everything that needs to be done on a project, much of it is left up to the Scrum software development team. This is because the team will know best how to solve the problem they are presented.
This is why in Scrum development, for example, a sprint planning meeting is described in terms of the desired outcome (a commitment to a set of features to be developed in the next sprint) instead of a set of Entry criteria, Task definitions, Validation criteria, Exit criteria (ETVX) and so on, as would be provided in most methodologies.
The primary artifact in Scrum development is, of course, the product itself. The Scrum model expects the team to bring the product or system to a potentially shippable state at the end of each Scrum sprint.
The product backlog is another artifact of Scrum. This is the complete list of the functionality that remains to be added to the product. The product owner prioritizes the backlog so the team always works on the most valuable features first.