the short answer
A Noul is Jev’s yes/no question primitive. It evaluates one condition against the supplied state and returns noul, the probability that the answer is yes or the statement is true, from 0 to 1. A Noul is not a Boolean, has no separate confidence field and needs an application-owned threshold calibrated for the specific decision and consequence.
- Question shape
- One yes/no condition
- Response
noulprobability from 0 to 1- Separate confidence
- None
- Best use
- Independent semantic conditions
What the Noul Value Means
A result near one favors yes, a result near zero favors no, and a result near 0.5 means the two outcomes have similar modeled probability. It does not describe intensity. “Is the customer frustrated?” and “How frustrated is the customer?” are different questions; the first can be a Noul and the second needs an ordered Score rubric.
Optional true and false criteria can define both sides of the boundary. Keep them aligned with the instruction. A reversed or contradictory definition makes the instrument harder to interpret and is a documented Jev 1.13 weakness.
Use Multiple Nouls for Independent Labels
When a message may be both a refund request and a complaint, ask two Nouls. A Choice would force the labels to compete and select only one. Each Noul can have its own threshold because the consequences and base rates may differ.
Interpret the Number as Probability of Yes
For the question “Does the final reply claim that a refund was created?”, 0.82 means the model assigns 0.82 probability to yes under this state and question. It is not 82% task completion, severity or general confidence. A different Noul—such as “Did the refund tool succeed?”—would measure a different condition and should usually be replaced by an exact tool-result check.
Application code can derive an action from the value, but the action is not part of the model response. The same 0.82 could trigger an automatic tag in a low-risk workflow, human review for a customer-impacting claim, or no action where the evidence is incomplete. The threshold guide derives bands from error cost rather than attaching a universal meaning to one number.
{
"noul": 0.82
}Example: Check One Claim Against Supplied Evidence
The Noul answers only the semantic question about what the reply claims. Code still checks the tool result exactly. Keeping those two checks separate reveals a useful failure: the agent may claim completion even though no successful tool event exists. The agent-trajectory guide shows how to preserve that evidence link.
| Part | Example |
|---|---|
| State | Customer request, final agent reply and the relevant refund-tool result |
| Noul question | Does the final reply claim that a refund was created? |
| True criteria | The reply states or clearly implies that the refund was submitted |
| False criteria | The reply does not make that claim or explicitly says it was not submitted |
| Application check | Compare the claim Noul with deterministic evidence that the refund tool succeeded |
Do Not Round Noul into Truth Too Early
- Store the raw value and the resolved model and question version.
- Fit action thresholds against held-out labels from the target workflow.
- Keep a review band when the cost of a wrong action is meaningful.
- Do not expect separately asked positive and negated Nouls to sum to one.
Write One Direct Condition and Test Its Boundaries
A Noul should correspond to one label a reviewer can assign from the same evidence. Define positive, negative and unscorable examples before tuning wording. If reviewers disagree because the condition contains two decisions or missing policy context, changing the threshold will not repair the instrument. The question-writing guide covers atomic criteria and leakage-resistant iteration.
| Problem | Hard-to-audit wording | Clearer split |
|---|---|---|
| Compound condition | Was the refund promised and correctly completed? | One Noul for the claim; code checks tool completion |
| Double negative | Is it not true that no escalation is needed? | Does this case need human escalation? |
| Undefined evidence | Is the answer grounded? | Does cited passage X support claim Y? |
| Severity hidden in yes/no | Is the incident serious? | Use a Score with observable severity levels |
Validate Probability and Operating Threshold Separately
Calibration asks whether events assigned similar probabilities occur at similar rates across a population. It does not certify an individual 0.82 prediction. scikit-learn documents reliability diagrams and proper scoring metrics; the Jev calibration guide adds split design, bootstrapping and drift controls for this interface.
- Sample representative positive, negative, rare and missing-evidence cases.
- Obtain labels without showing reviewers the Jev result.
- Freeze the model, Noul wording, criteria and state projection.
- Group predictions into probability bands and compare predicted with observed positive rates.
- Report Brier score, precision and recall at candidate thresholds, plus automation coverage and review volume.
- Repeat by language, source, customer or other consequential slice and after every instrument change.
Common Noul Mistakes Change the Question Being Measured
Test paraphrases, hard negatives, missing evidence and adversarial text before deployment. Store the exact question and state-projection version with every result. The dataset guide explains label construction, and evaluate the evaluator covers calibration and slice errors.
- Combining two conditions with “and,” then treating one failure as evidence about both.
- Using a Noul for severity when the real answer needs ordered levels.
- Treating missing evidence as a confident no instead of an unscorable case.
- Writing positive and negative criteria that overlap or contradict each other.
- Copying one threshold across languages, model versions or consequences.
FAQ
Is Noul just a Boolean?
No. It returns a probability from zero to one. Application logic may derive a Boolean at a measured threshold, but retaining the original value preserves uncertainty.
Does Noul return confidence?
No. The Noul value is the probability of yes. Choice and Score have separate confidence fields.
Why is a Noul near 0.5 not medium severity?
Because the axis is yes versus no, not low versus high intensity. Use Score with ordered descriptive levels for severity.
Can several Nouls be true?
Yes. Separate Nouls are independent conditions, so several may have high yes probability. That is useful for multi-label classification.
Sources
Checked against the sources below on September 22, 2026. Model versions, prices and limits change.
- TypeSafe AI docs: Primitives
- TypeSafe AI docs: Confidence
- TypeSafe AI docs: Jev 1.13 jaggedness
- scikit-learn: Probability calibration and reliability diagrams