ADF uses the unique Te Velde - Baerends numerical integration scheme, in which the grid is automatically adapted to the available basis functions and to the number of significant digits demanded by the user through a single input parameter. It is straightforward to do very accurate integrations with far fewer points than in less highly developed schemes. For some more details see also numerical integration details.
ADF User Documentation: numerical integration
ADF-GUI: accuracy and efficiency
Related: numerical integration details
