Strength:
Physical attack power		  
     
  Constitution:
Maximum HP, HP Regeneration rate		  
     
  Accuracy:
Hit rate, Critical rate, Parry		  
     
  Agility:
Dodge, Shield block rate, Parry rate, Chance of canceling casting		  
     
  Intelligence:
Magical attack power, Magical crit rate		  
     
  Spirit:
Maximum MP, MP Regeneration rate		  
     
     
  The base stats remain constant as you level, and you don't get more stats to allocate. However there may be gear, enhancement stones or stigmas with stat modifiers.  
     
  The exact base stats for each class can be found here