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Jev Guardrails

Mock carrier support agent with the guardrail layer built twice behind one interface: chat-model JSON judging versus TypeSafe Jev typed questions over the same 25 rules.

Stars
3
Language
Python
Published by
Community
Author
deepansh-saxena
Last verified
Oct 2026

Comparing LLM-as-judge vs TypeSafe Jev for agent guardrails: same rules, same agent, measured on cost, latency, calibration and coverage.

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1
Last pushed
Updated Sep 2026

Repo stats from the GitHub API, cached Oct 2026.

About this project

The same agent, the same 25 rules, the same thresholds. The only variable is what answers the question. A mock carrier support agent whose guardrail layer is built twice, behind one interface, so the two can be measured against each other on identical traffic. 51 labelled cases, both backends, same rules, same thresholds, same agent:

Quoted from the project's README. Read the full README.

Highlights

  • Same LangGraph triage agent routing to six desks over 43 mock tools.
  • Desk prompts shrink from 8,694 to 3,004 chars by removing clauses from prompt.
  • Single-reply full coverage reported near 200 ms for Jev versus 5,500 ms for LLM.
  • Five guardrail layers from deterministic gates to scope and behavioural rubric.

Watch out

Genuine errors were 3 versus 3 after excluding provider-filter artefacts, and one Jev false refusal remains. Copy reviewed against the repository README on 2026-10-04, not from running it.

Questions about this entry

Short answers drawn from the linked project or page.

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