SPACI score report for 2xai in ASTRAL 2.02:

PDB Entry: 2xai
SPACI score: 0.27
AEROSPACI score: 0.27

Experiment type: XRAY
Resolution: 2.58
R-factor: 0.2376
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: -1.496
WCK2 WHAT_CHECK Ramachandran: -2.271
WCK3 WHAT_CHECK Chi angles: -2.178
WCK4 WHAT_CHECK Backbone: 0.912

Note: Here are links to pages about PROCHECK and WHAT_CHECK.

Here is the full WHAT_CHECK report on this protein (linked from the WHAT_CHECK site).