Documentation of property flow in MSBuild Task

Where is the documentation describing which properties do, or do not, flow from a parent project to the project invoked via an MSBuild task? For example consider:

``` xml

Oh yeah

````

When Example.proj is being built which of the following property types are passed from Parent.proj to Child.proj:

- Global properties: are the global properties of Parent.proj available in Child.proj?
- Environment properties: no environment, the original environment passed to Parent.proj or any modifications to environment properties which were done by Parent.proj?
- Local properties: what is the value of `$(WhatsThat)` inside Child.proj?

It's easy to drum up a few experiments to see what the values are here. But I'm a bit wary of using experiments here because there are subtlties to MSBuild that I may be missing. Curious where there is documentation specifying what the intended behavior is here.