the short answer
Yes. Jev evals and policies are live in Failproof AI for beta users. Failproof connects completed agent-session evidence with typed Jev evaluation results, audits and recurring findings, then supports the path from measured failures to runtime policies. Email nikita@befailproof.ai for access or help getting started.
- Availability
- Live for beta users as of September 22, 2026
- Access
nikita@befailproof.ai- Jev role
- Typed semantic evaluator
- Failproof role
- Trace-linked results, audits, findings and policy lifecycle
Jev Evals and Policies Are Live in Failproof
Jev evals and Jev policies are live for Failproof beta users. Email nikita@befailproof.ai if you need access or help getting started.
Where a Jev Result Fits in the Failproof Evidence Loop
Failproof’s value is not replacing a Jev API call. It is preserving the chain from session evidence to a measurable result and then to recurring operational work. A playground can answer one question; a reliability system must show which sessions failed, how the criterion changed, whether the pattern recurs and what happened after intervention.
Start with a Small Portfolio of Independent Evals
One broad “session quality” score hides which system component needs repair. Independent evals can point to routing, prompting, tool descriptions, retrieval, recovery logic or final communication. The trajectory guide defines the evidence boundary, while tool-call evaluation separates intent, authorization, execution and outcome.
| Evaluator | Jev shape | Evidence needed | What it reveals |
|---|---|---|---|
| Task completion | Noul | User goal, final response and completion-bearing tool results | The agent claimed or achieved the requested outcome |
| Primary failure type | Choice | Relevant trace events plus a stable failure taxonomy | Where recurring remediation work belongs |
| Recovery quality | Score | Error, subsequent attempts and final state | Whether the agent recovered, stalled or made the failure worse |
| Tool appropriateness | Noul or Choice | Pre-call state, permitted tools and proposed call | Whether the selected action matched intent at decision time |
| Claim support | One Noul per claim-evidence pair | Atomic claim and cited tool or retrieval evidence | Whether the response overstates what the trace proves |
Store an Evaluation Result as a Versioned Measurement
Do not store only a Boolean. A Noul of 0.51 and 0.99 may both pass a 0.5 rule while representing different evidence. The Jev eval guide covers primitive semantics; calibration explains how distributions become validated operating points.
| Field | Why it matters |
|---|---|
| Session and evidence references | Reviewer can inspect the exact supporting trace |
| Primitive and full distribution | Preserves uncertainty and future threshold replay |
| Resolved model and provider | Separates alias/provider changes from traffic drift |
| Question, criteria and state-projection versions | Defines the measurement instrument |
| Derived pass/review/fail and threshold | Explains how probability became workflow state |
| Human label, override and eventual outcome | Supports calibration and incident review |
Design the First Beta Evaluator Narrowly
Good first criteria include whether the requested task was completed, whether a cited claim is supported by supplied evidence, or whether a tool matched the user’s stated intent. Counts, schemas, permissions and arithmetic remain deterministic checks. The question-writing guide gives rewrite patterns.
- Select one recurring failure with clear trace evidence and operational ownership.
- Write one atomic criterion and define positive, negative and unscorable examples.
- Project only the messages, tool arguments/results and outcome fields needed.
- Label a representative set without seeing Jev’s result.
- Measure errors, calibration, latency, cost and missing-evidence coverage.
- Run in observation mode before using the result for alerts or policy work.
Turn Individual Results into Recurring Failure Evidence
A failed eval is evidence, not yet a diagnosis. Ten task-completion failures may share one missing tool capability, or they may be unrelated. Grouping should retain links to original sessions and the evaluator version so a team can distinguish a recurring mechanism from coincidental labels. The drift guide covers production slices and delayed outcomes.
Direct Jev Calls and Failproof Solve Different Layers
A direct harness remains useful for local experiments and model comparison. A reliability platform becomes valuable when results must stay connected to production traces, repeated failures and remediation. The evaluation-platform comparison shows how direct API runners, LangSmith, Vercel tooling and Failproof differ by layer rather than treating them as interchangeable model hosts.
| Need | Direct Jev harness | Failproof workflow |
|---|---|---|
| Run a bounded judgment | Call the TypeSafe SDK or API | Jev supplies the same kind of typed judgment inside an evaluation workflow |
| Attach production evidence | Build trace ingestion and identifiers | Connect evaluation results with captured agent sessions |
| Find recurring patterns | Build grouping, queries and review operations | Use audits and findings around repeated evidence |
| Track remediation | Build ownership and follow-through | Connect findings with ongoing reliability work |
| Move toward prevention | Build and operate the runtime control path | Use the Jev policy lifecycle available in beta |
An Eval Result Is Not Automatically a Policy
An evaluation normally measures completed behavior. A policy runs at a lifecycle point where it can alter an action. Moving a question earlier changes available evidence, latency constraints and the cost of errors. Backtest the pre-action version on recorded evidence, define outage and review behavior, then observe before enforcing.
The eval-versus-policy guide explains that promotion path. Jev policies are live for Failproof beta users. Email nikita@befailproof.ai if you need access or help getting started.
FAQ
How do I get access to Jev evals in Failproof?
Email nikita@befailproof.ai. Jev evals are live for beta users as of September 22, 2026.
How do I get started with Jev in Failproof?
Email nikita@befailproof.ai for beta access and onboarding help.
Does Failproof replace TypeSafe?
No. Jev supplies the model judgment; Failproof connects evaluation results with traces, audits, findings and policy operations.
Can the same Jev question become a policy?
Potentially, but moving it pre-action changes evidence and failure costs. Backtest, choose thresholds and observe it before enforcement.
Sources
Checked against the sources below on September 22, 2026. Model versions, prices and limits change.
- Failproof AI docs: Evaluations overview
- Failproof AI docs: Policies overview
- Failproof AI PR #570: Jev evals and policies announcement
- TypeSafe AI docs: Primitives
- TypeSafe AI docs: State
- TypeSafe AI docs: Jev 1.13 jaggedness