Scrum ceremonies and all the attendees of all the ceremonies.

There are no ceremonies in Scrum but there are events.

What does the Scrum Guide say about them? Don't think so much in terms of inputs and outputs, but of each event as providing a formal opportunity to inspect and adapt something.

Ceremonies could have input and outputs.  But events have purpose.  An event is something that happens.  A ceremony is something that is planned.  

The events that are explained in the Scrum Guide also explain the intention behind them. If you think of an event, such as a holiday festival, there is an intention of celebrating that holiday.  The may be some planned activities and even a ceremony but the event itself is fairly free form for the attendees.  That is true of all the Scrum events.  They could have some planned activities, such as a retrospective exercise to capture items for discussion, but there is a purpose that people are gathered and it is up to them to achieve it. 

Scrum is a framework.  Frameworks provide structure and support.  Consider the framework that is put up when building a house.  It supports the structure.  But how the different areas built within the structure are actually used is entirely up to the people that occupy it.  Sure, some of the areas might be built for specific purposes, i.e. kitchen or toilet, but even those can be used for other purposes if the occupants so choose. 

What you are expecting is for Scrum to be a methodology.  Methodology have specific ways that things are to be done with specific expected outcomes.  Scrum allows for use of methods within the framework but there are none prescribed that have to be used.