Answers & ConfidenceReject optionSelective prediction
Selective decision
A decision that is allowed to abstain instead of answering, trading coverage for accuracy on the cases it does handle.
- Category
- Answers & Confidence
- Also known as
- Reject option, Selective prediction
- Related terms
- 5
- Directory entries
- 38
- Docs
- docs.typesafe.ai
- Added
- 2026-10-12
Definition
A selective decision returns an answer only when confidence clears a floor, and otherwise abstains: it routes to a person, a slower step, or an explicit unknown. The abstain option is what makes the accuracy on the answered cases higher than the accuracy over everything.
Jev supports this through the probability it already returns — a middle Noul value or a low confidence is the signal to abstain — so the coverage and accuracy trade-off is a threshold you choose rather than a separate model.
Tagsconfidencedesign
Related terms
Definitions that connect to this one.
UncertaintyThe honest "I'm not sure" signal that lets a system defer instead of guessing, exposed through probabilities and confidence.Answers & ConfidenceConfidence gateA threshold on confidence that decides whether code acts, confirms first, or escalates to a person or a bigger model.Answers & ConfidenceThresholdThe value your code compares against a score, a Noul probability, or a confidence to turn an answer into an action.Answers & ConfidenceFail closedWhen the model errors, times out, or lacks evidence, the system escalates or blocks instead of allowing the action.EcosystemHuman reviewThe explicit path for uncertain or high-stakes cases: route to a person instead of acting on a low-confidence answer.Patterns
From the Jev directory
How TypeSafe reports certainty, how it differs from probability, and how to use it architecturally to gate and route decisions.
Jev Practices & PatternsDocs#official#confidence#routing
Official
The three TypeSafe question types, the typed answers they return, how to choose between them, and how to ask several in a single call.
Jev Practices & PatternsDocs#official#primitives#choice
Official
The Python response models: SystemOneResponse groups answers by id, and records the model name, token usage, and request id.
Jev Repos & SDKsDocs#official#docs#sdk
Official
A 3D robot that understands without generating text: one TypeSafe call per turn with nine typed questions, then code decides whether to act, ask, or shrug.
Jev CookbooksPlayground#community#playground#embodied-agent
Community
10GitHub stars
CLI that fits a per-question confidence threshold to a target accuracy on your own labeled data, verifies it on a held-out split, estimates how much traffic still needs an LLM, and re-checks locked thresholds in CI. It publishes no Jev results of its own.
Jev Practices & Patterns#community#python#calibration
Community
abhixhek/jevcalPython
abhixhek/jevcalPython7GitHub stars
A Ruby client for TypeSafe's System One API that returns typed Noul, Choice, and Score answers, validates obvious input mistakes before spending a request, and pools HTTP connections across threads.
Jev Repos & SDKs#community#ruby#sdk
Community
joshmn/typesafe-sdkRuby
joshmn/typesafe-sdkRuby32 more matching entries in the full directory.
From the Jev community
Posts from builders shipping with Jev right now.