Raw DNA and FASTA are gene-called with Pyrodigal and translated for you; GenBank CDS features are translated from the annotation; a protein is wrapped in a <+> strand marker; a mixed-format string (<+>MKV…<+>acgt…<->…) is used as is. One token is one amino acid, one nucleotide, or one strand marker, so a typical bacterial locus (~88 % coding) fits about 10 kb in 4,096 tokens and pure non-coding DNA about 4 kb. Longer input is cut at a gene boundary and the summary says what was kept. Heads: RNA base pairing, DNA repeats and protein contacts.