Checker searches for incomplete reaction map. A reaction with two or less atom maps (both on the reactant and the product side) is considered an incompletely mapped reaction.
Fixer offers mapping the reaction (mapreaction).
Example :
Reaction Map Error Checker (reactionmap) | 
Warning: | Fix | 
|---|---|---|
Mapping (mapreaction) | 
||
| Find incomplete reaction map |     ex_reactionmap_ch | 
    ex_reactionmap_f | 
   ex_reactionmap_ch
   ex_reactionmap_f