PROBATUM-1/E · the evaluation profile · draft v0.1

What it scored, honestly.

Backtest overfitting and benchmark contamination are the same crime: a maximum reported as a mean. The same four commitments, applied to evaluation: the model, the test set, the scoring rule and the number of runs, bound inside the proof. Text unchanged from VTR-1/E v0.1; relabelled.

A specification for review. No engine era implements it.

DRAFTStatus
E-01 … E-23Clauses
E1 → E4Conformance classes
0c34558362492212…sha256 of the draft

Licence: PROBATUM Open Reliance Licence v0.1 (draft): read, cite, verify and implement freely; never fork; never issue under the name without conformance. Profile zero (VTR-1) stays CC BY 4.0. Read the licence. Nothing on this page is in-circuit unless its chip says LIVE.

§00Abstract

An evaluation score is a claim of the form: a model, applied to a test set under a scoring rule, obtained this number. Today that claim is checked by trust. The evaluator chooses the test set, may have trained on it, may have run the benchmark many times and reported the best run, may have changed the model between the run and the release, and may have changed the scoring rule. None of this is visible in the number.

Backtest overfitting and benchmark contamination are the same crime. A trading record mined across thousands of strategies and an evaluation score mined across thousands of checkpoints, prompts and seeds both report a maximum and call it a mean. VTR-1 closes this for trading records with four commitments: the procedure, the data, the cost rule and the number of trials, with the trial count bound in-circuit rather than reported. This profile applies the same four commitments to evaluation.

A conforming evaluation credential proves, without revealing the model: that a committed model was scored on a committed test set under a committed scoring rule, that the test set was committed before the model could have seen it, that the number of runs across checkpoints, prompts, seeds and configurations is bound, and that the reported score is the one the committed procedure produced. Every requirement carries a stable identifier, E-01 onward.

The key words MUST, MUST NOT, SHALL, SHOULD and MAY are used as in VTR-1.

§01Scope

This profile governs credentials whose statistic is a score of a model or agent on an evaluation set: accuracy, exact match, pass@k, win rate, calibration, Brier score, task success, cost-normalised success, or any scoring rule that is a deterministic function of model outputs and committed labels.

It governs the claim, not the model. It does not certify capability in general, safety, alignment, intent, or performance on data other than the committed set. A conforming credential proves that a score is honest and belongs to a specific, committed model. Nothing more.

Out of scope: scores that depend on a human rater's judgement unless the ratings are themselves committed before the model outputs exist; scores on sets the evaluator cannot commit publicly in hashed form; and any construction that proves the absence of training-set leakage, which no current construction does (see §07).

§02Definitions

Model commitment. H(model_artifact ‖ model_salt): the complete inference procedure (weights or API identity and version, system prompt, tool configuration, decoding parameters, scaffolding) and 32 secret random bytes. Identical to the VTR-1 sealed-path commitment.

Test set commitment. A Merkle root over the test items, each leaf H(input ‖ label ‖ item_salt), published with a timestamp anchor before any scored run. Items MAY stay private; the root is public.

Scoring rule commitment. The hash of the deterministic scoring function and its parameters (normalisation, tolerance, k, judge model identity if a model judge is used).

Run. One execution of the committed model over the committed test set under the committed scoring rule with a committed seed and configuration.

Run ledger. A Merkle commitment to every run the evaluator executed on this test set with any model version, in order. Its leaf count is N_runs. Each leaf commits the model commitment, seed, configuration and the score obtained.

Reported score. The score the credential attests. It MUST be the score of a run named by index in the run ledger.

Selection-adjusted score. The reported score corrected for the number of runs, by the method in §05.

Holdout class. The relationship between the test set and the model's possible training data, declared and, where possible, proven (§04).

§03Conformance classes
ClassNameProvesAnswers
E1ScoredA committed model obtained the reported score on a committed test set under a committed ruleIs this number what the procedure produced?
E2CountedE1, plus the run ledger and the selection-adjusted scoreHow many tries sit behind this number?
E3Sealed-setE2, plus the test set root was anchored before the model commitment existed, and the model's declared training cutoff precedes the set's creationCould the model have seen the test?
E4ReproducedE3, plus an independent party re-ran the committed model on the committed set inside the proof system and obtained the same scoreDoes it reproduce when someone else holds the keys?
§04Holdout and contamination
§05The run ledger and selection
§06The eval-check

A party about to rely on a score (a buyer, a deployer, a leaderboard, an allocating agent) performs, before relying:

The eval-check reads properties. Which class, adjustment or canary result is sufficient is the relying party's policy.

§07Boundary

This profile does not certify, and a conforming credential MUST NOT be presented as certifying:

§08Machine-readable verdict
{ "profile": "VTR-1/E 0.1", "class": "E3", "score": { "rule": "exact_match", "raw": 0.812, "selection_adjusted": 0.774, "n_items": 1200 }, "credentialDigest": "sha256:…", "era": "<image id>", "modelCommitment": "0x…", "testSetRoot": "0x…", "testSetAnchoredAt": "2026-09-30T00:00:00Z", "scoringRuleHash": "0x…", "runLedgerRoot": "0x…", "nRuns": 17, "reportedLeaf": 11, "trainingCutoffDeclared": "2026-06-01", "testSetCreated": "2026-09-28", "holdout": { "class": "anchored-before-run", "proven": true, "contaminationFree": "not provable" }, "canary": { "present": true, "score": 0.08 }, "bundle": "https://…", "anchors": ["bitcoin:…"] }
§09Relationship to existing evaluation tooling (informative)
Tool or standardWhat it givesWhat this profile adds
lm-eval-harness, Inspect, HELMReproducible scoring codeProof that the committed code was run on the committed set by the committed model, with runs counted
Public leaderboardsA number and a submitterA verdict object with class, N_runs, holdout and a re-runnable proof
Private test sets (held by a lab)Contamination resistance by secrecyThe same resistance without trusting the holder: root anchored, items optional, canaries reported
Model cardsDeclared training cutoffThe declaration committed and checked against the set's anchor date
Agent benchmarks (task success)Trajectories and pass ratesTrajectory outputs as model outputs under a committed deterministic rule; cost-normalised success as a rule parameter
§10Security considerations
AttackDefence
Running the benchmark many times, reporting the bestE-10 to E-14: run ledger, N_runs bound in-circuit, selection-adjusted score beside raw
Training on the test setE-05, E-06, E-08: anchored root before run, cutoff vs creation, canaries; residual risk stated (E-07)
Swapping the model after the runE-01: score bound to the model commitment; a swap is a new claim
Changing the scoring rule or dropping hard itemsE-02, E-03: rule committed, every item scored
Judge-model gamingE-02: judge committed and inside the proof
Publishing the set, then re-using itE-09: published sets are retired

Residual risks: paraphrased contamination that canaries do not catch; an evaluator running many test sets rather than many runs and reporting the friendliest set (the set-selection analogue; a future version may require a set ledger); collusion between evaluator and set author.

§11Relationship to VTR-1 and VTR-1/A

This profile adds E-01 to E-23. It reuses the sealed-path model commitment, the trial-ledger construction (as the run ledger), era law, the verdict transparency log, receipts and the check-before-reliance pattern unchanged. It removes nothing and weakens nothing in VTR-1. Governance follows VTR-1 §6.

§12Open questions for review
  1. Should E3 require a minimum gap between training cutoff and set creation?
  2. Is a set ledger (every test set an evaluator has tried) feasible without revealing how many sets a lab holds?
  3. Which selection-adjustment method should be normative at v1.0: expected maximum under exchangeability, or a bootstrap over the ledger's committed scores?
  4. How should cost-normalised agent success commit to prices that change over time?
Appendix A · Requirement index
IdLevel§Subject
E-01MUST3Score bound to model, set and rule commitments
E-02MUST3Deterministic rule; committed judge
E-03MUST3Every item scored
E-04MUST3Class stated and shown
E-05MUST4Set root anchored before run
E-06MUST4Cutoff and creation dates committed
E-07MUST4Holdout declared vs proven; contamination not provable
E-08SHOULD4Canary items
E-09MUST4Published sets retired
E-10MUST5Append run before score known
E-11MUST5Append-only ledger
E-12MUST5N_runs bound in-circuit
E-13MUST5Selection-adjusted score beside raw
E-14MUST5Reported score is one leaf
E-15SHOULD5Pre-register the leaf
E-16MUST6Retrieve and hash-check
E-17MUST6Verify proof under era
E-18MUST6Root and rule match expectation
E-19MUST6Read class, dates, canary, adjustment
E-20MUST NOT6Fail-closed conditions
E-21MUST7Class, N_runs, holdout shown beside score
E-22MUST8Verdict object
E-23SHOULD8Callable eval-check