Currently, the VIATRA2 Documentation consists of the following documents:
Getting Started Tutorial
This document describes the basics of the VIATRA Model Query and Transformation framework, including the development environment
and runtime API. This document is available from eclipse.org/viatra/documentation/tutorial.php,
and starting from VIATRA 1.6 is also installed into the Eclipse Help. You should start here.
The VIATRA Wiki contains detailed documentation related to VIATRA.
This is the most exhaustive documentation for VIATRA, it includes both end-user and contributor-related documentation.
However, some parts of it are more or less outdated.
Eclipse Help Center (Oxygen)
Starting with the Oxygen release at June 28th, 2017 the VIATRA help should be included in the Eclipse Help Center.
Before the Oxygen release, VIATRA is not available from this location.