Reference-free evaluation of large language model (LLM) creativity relies on perplexity, entropy, and top-1 margin. We show that a much stronger signal lives one step earlier in the pipeline: in how sampling temperature \emph{reshapes} the model's token distribution before the next token is drawn. On Llama-3.1-8B-Instruct generations of 500 open-ended creative prompts at
T∈{0.3,0.8,1.5}, a single per-token feature derived from this reshaping predicts the within-prompt creativity rank at Spearman
ρ=0.918 against an averaged gpt-4o,/,gemini-2.5-pro judge (
n=500) and
ρ=0.870 against a three-rater human-majority ranking (
n=150). Each of four standard reference-free baselines (self-perplexity, mean predictive entropy, top-1 margin, gzip compression ratio) tops out at
∣ρ∣≈0.76 on both ground truths: a gap of
+0.165 on averaged-LLM and
+0.110 on human-majority, both far larger than the spread among the baselines themselves. The two ground-truth panels agree with each other at
ρ=0.83, above the inter-human ceiling of
ρ=0.77, so the comparison is not bottlenecked by judge noise. Mechanistically, the win comes from a sharp distributional signature of the incoherence regime: at
T=1.5 the cumulative-mass width
n95(q) inflates from
∼1 to
∼131 tokens and post-temperature mass leaks off the pre-temperature top-
90% plausible set by about
13 percentage points. The per-token aggregates do not separate
T=0.8 from
T=0.3; discriminating the two coherent regimes is left to sequence-level features.
V. S. Raghu Parupudi, Harsha Ponnada, Aditi Kaushal +3