While the reactions in NiCOlit are all extracted from publications referenced in the same review, they cover a wide range of possible mechanisms. As most of the publications extracted do not provide detailed mechanistic study of the reaction performed, a discrimination was DFT model performances for the different splits displayed in A. The performances displayed represent an average result over 10 random splits for the random task and all the possible substrates, DOI or coupling partner categories splits for the three remaining tasks.