Determining Read Groups Which Read Groups are correct:

java -Xmx4G -jar picard.jar AddOrReplaceReadGroups \
I=$SNIC_TMP/WCRO84_S23_L005.bam \
O=WCRO84_S23_L005.bam \
RGID=WCRO84_S23_L005 \
RGLB=WCRO84 \
RGPL=illumina \
RGPU=WCRO84_S23_L005 \
RGSM=WCRO84


or

java -Xmx4G -jar picard.jar AddOrReplaceReadGroups \
I=$SNIC_TMP/WCRO84_S23_L005.bam \
O=WCRO84_S23_L005.bam \
RGID=WCRO84_S23_L005 \
RGLB=WCRO84_S23_L005 \
RGPL=illumina \
RGPU=WCRO84_S23_L005 \
RGSM=WCRO84_S23_L005


Or is a better way to determine read groups?

Thank you in advance,
Usually it doesn't actually matter, but if you want it to be very correct:

RGID=SomeLibraryID \
RGLB=SomeLibraryID \
RGPL=illumina \
RGPU=Some_Sequencer_ID \
RGSM=SomeSampleID


That assumes you have one library per sample and aren't splitting the output BAM files by lane.