Sever silently fails on bad input instead of erroring gracefully

[Sevoii]

Example:

{"enable_reddora":true,"enable_uradora":true,"enable_shanten_down":true,"enable_tegawari":true,"enable_riichi":false,"round_wind":27,"dora_indicators":[23],"hand":[34,5,9,11,12,12,14,14,15,17,22,24,26,9],"melds":[],"seat_wind":27,"wall":[4,4,4,4,3,3,4,4,4,2,4,3,2,4,2,3,4,3,4,4,4,4,3,3,3,4,3,4,4,4,4,4,4,4,0,1,1],"version":"0.9.1"}

{"enable_reddora":true,"enable_uradora":true,"enable_shanten_down":true,"enable_tegawari":true,"enable_riichi":false,"round_wind":27,"dora_indicators":[16],"hand":[0,2,5,7,10,11,15,16,21,21,22,24,24,22],"melds":[],"seat_wind":27,"wall":[3,4,3,4,4,3,4,3,4,4,3,3,4,4,4,3,2,4,4,4,4,2,2,4,2,4,4,4,4,4,4,4,4,4,1,1,1],"version":"0.9.1"}

{"enable_reddora":true,"enable_uradora":true,"enable_shanten_down":true,"enable_tegawari":true,"enable_riichi":false,"round_wind":27,"dora_indicators":[21],"hand":[2,2,3,34,8,9,12,35,13,14,22,25,27,27],"melds":[],"seat_wind":27,"wall":[4,4,2,3,3,4,4,4,3,3,4,4,3,2,3,4,4,4,4,4,4,3,3,4,4,3,4,2,4,4,4,4,4,4,0,0,1],"version":"0.9.1"}