The UK Government has released a number of documents that aim to aid understanding of the Withdrawal Agreement and the Political Declaration on the future relationship and support parliamentary assessment of the deal. These materials have also been laid before Parliament.

The published documents are as follows:

EU Exit: Taking back control of our borders, money and laws while protecting our economy, security and Union
EU Exit: Assessment of the security partnership
EU Exit: Long-term economic analysis
EU Exit: Long-Term Economic Analysis Technical Reference Paper

The full set of documents is also available here.