Newick: coffee cultivar tree, by gpt-6-luna
gpt-6-luna · round 2 of 2 · seed 1$0.00SVGtree.nwk
tree.nwk · 2 lines
((Caturra:8,Bourbon:8,Typica:8,Gesha:8):2,(((SL28:4,Pacamara:4):2,(Maragogipe:4,Mundo_Novo:4):2):2,((Catuai:4,Villa_Sarchi:4):2,(Bourbon_Vermelho:4,Java:4):2):2):2);
round 1 of 2
A family tree of twelve coffee cultivars, by GPT-6 Luna, the render after round 1
12What the model saw after each round. The picture above is the round that was scored, round 2.

Bourbon is in the split of four, and Bourbon Vermelho, which is Bourbon, is on the other side of the root.

modelopenai/gpt-6-lunatasknewick-coffee-cultivars@v1, checks c1, harness h1date2026-10-14rounds2 of 8 allowed, 12 minutes on the clockcost$0.0016thinkingmediumtokens9,760 in, 2,428 out, of which 2,070 reasoningtime43 s
Valid Newickdecided by a number, from the filepass
Twelve cultivarsdecided by a number, from the filepass
Every tip leveldecided by a number, from the filepass
One split of fourdecided by a number, from the filepass
read the post
its other runs
the prompt it was given
Write an ultrametric Newick tree of twelve coffee cultivars with exactly one polytomy, of four.
Frozen at v1. This model got this and nothing else.
ground truth

The tree read with Biopython, every path from the root to a tip added up from its branch lengths, and the children of every node counted. The checks only read the brackets. Whether a cultivar sits beside its relatives is not checked here, and the post of 14 October looks at that by eye. How it is scored, and this run's files on GitHub.