Well, lets start with more specific concepts: Uncertainties are things that are not known, or known only imprecisely. An uncertainty has an effect which is associated with a risk, that is, an uncertainty has a risk associated. A risk is a negative effect of an uncertainty over the project´s objective.
There are uncertainties of requirements, process, resources, and so on. Specific risks are: Technical Risk, Cost Risk, Schedule Risk.
Form of documenting a risk: "Given that [CONDITION], there is a possibility of [DEPARTURE] adversely impacting [ASSET], thereby leading to [CONSEQUENCE]."
CONDITION: Key fact-based situation or environment that is causing concern.
DEPARTURE: It is an undesired event that is made credible or more likely as a result of the CONDITION. It is a change affecting the baseline project plan.
ASSET: It represents the primary resource that is affected by the individual risk.
CONSEQUENCE: It describe the impact(s) in terms of failure to meet requirements that can be measured, described, and characterized.
So, based on these concepts, we have the following questions:
What are the more common uncertainties in your agile process? What are the more common risks in your agile process?