Use cases· Last updated 2026-09-21

Code review failure modes with Jev

Linters, typecheckers, and SAST prove or pattern-match. Jev can decide whether leftover PR language looks like “needs security eyes” or “reviewer load is high.” It will not compile the repo or write the fix.

This unofficial page is the failure modes slice of the code review routing pack. Intent: apply the Jev (TypeSafe System One) decision model to code review routing failure modes. Primary search language: Code review Jev failure modes. Confirm patterns on docs.typesafe.ai. This site does not sell, issue, or proxy TypeSafe keys. Use a credential you already have from the console or a documented gateway.

Independent angle (cover ≠ clone): Analyzers own AST truth; Jev routes review judgment on PR prose + small hunks. Not a SAST clone and not a rival “agent skill” IA photocopy.

Code review use-case context

Code review routing breaks in product-specific ways. This page lists those modes so you can write tests — not a generic “AI can be wrong” essay, and not a rival limitations-page clone.

Hub: Use cases. Compare, when the other tool is the real job: code analyzers.

Failure Modes inputs

Many failures start as contract violations (distractors, missing PR description + selected hunks text). Canonical shape:

{
  "pr": { "id": "1234", "title": "Relax auth on internal debug route", "body": "Temp bypass for the oncall drill." },
  "hunks": ["- if (!user) return 401;", "+ // skip auth in staging"],
  "ci": { "sast_blockers": 0, "lint_errors": 0 },
  "policy": { "secrets": "Flag prose that describes committing keys or disabling auth in prod-shaped paths." }
}

Decision signals and actions

• Replacing SAST with a Noul — analyzers win on formal defects (compare).
• Sending minified bundles and expecting a security verdict (jaggedness).
• Asking Jev to write the patch.
• Auto-merging on merge_ok_if_ci without a high floor and green analyzers.
• Invented defect-escape rates.

HTTP vs application:

Do not treat a Noul of 0.5 as a “medium” code review routing score — it means yes and no are equally likely. Conjunctions stay in your code.

Guardrails and escalation

Fail closed: do not auto-approve the merge. Schema-safe answers are not factual correctness. TypeSafe’s confidence-gated examples use a lower bar for recoverable reads than for irreversible actions. Those numbers are illustrations. For code review routing, treat auto_approve_merge as the high bar (approving a merge or skipping required review). Tune on labels — see offline evaluation.

Evaluation and rollout notes

Your canary set should include each bullet above.

• Missed auth-bypass language on a planted set
• False security pages (reviewer fatigue)
• Override rate after humans read the same hunks

Pin jev-1.13.0 (the versioned id) after you fit thresholds. jev-latest and the marketing line jev-1.13 can move. Log the response model. TypeSafe’s published list price for jev-1.13 is $0.042 per million input tokens (vendor claim — confirm on the models page); output tokens are free on that same page. Unused distractors still bill as input.

Official Python and JavaScript SDKs read TYPESAFE_API_KEY and retry documented 429/529. This site does not sell, issue, or proxy TypeSafe keys. Use a credential you already have from the console or a documented gateway.

Pack map

FAQ

If the API returns 200, is the decision good? 200 only means the call parsed. Low confidence, Noul ≈ 0.5, or a policy miss are application failures.

Where do official weaknesses live? TypeSafe’s jev-1.13 jaggedness note — distractors, arithmetic, adversarial content. We do not invent more.

Where is the rest of the Code review pack? Start with Code review evaluation and Code review decision workflow. Cluster hub: Use cases.

Does the TypeSafe agent skill replace our linter? No. It teaches agents to batch questions. Analyzers still own AST truth. See agent skill.

Can Jev score cyclomatic complexity? Do not use a 2–10 Score as complexity math. Count in code or skip.

What this page does not claim

• Not a SAST, linter, or merge bot product.
• No published precision on vulnerability finding.
• Not official TypeSafe.
• Official TypeSafe status, or that jev.pro issues API keys.
• That a schema-constrained answer is automatically factually correct.

Disclaimer

This is an independent unofficial site and is not affiliated with TypeSafe AI; official documentation is available at https://docs.typesafe.ai.

Primary documentation: https://docs.typesafe.ai. Hub: Use cases.