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vocabstruct
confirmedPython · CPUInference & servingJuly 6, 2026
the question
What is the LLM tokenizer vocabulary, exactly?
what came out
One shared, byte-complete, merge-dominated object: byte-for-byte identical across the 1.5B and 0.5B (same 151,936 tokens, same hash), lossless, 99.81% learned BPE merges on a 256-token byte base. A full census, every number exact -- 3 of 4 predictions held (the length distribution wasn't unimodal).
method & receipts
- Result: confirmed
- Pre-registered — the prediction was written down and committed before the run.
- Reproducible — one script re-runs the whole thing from scratch.
- Independently reviewed — an adversarial review pass, kept in the repo.
- Machine-readable claims — every reported number, in a checkable file.
- Tested — a correctness/benchmark suite ships alongside the code.
→ read the code and re-run it
github.com/v-code01/vocabstruct