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Grounded AI

One Python interface for evaluating what LLM apps and agents say and do. Its CascadeEvaluator asks a decision model first — Jev, OpenAI's Decisions API, or any model served at /v1/systemone — keeps confident answers, and sends only the rest to an LLM judge.
Stars
71
Language
Python
License
MIT
Reading time
2 min
Published by
Community
Author
grounded-ai
Last verified
Oct 2026

Highlights

  • CascadeEvaluator asks a decision model first — Jev, OpenAI's Decisions API, or any model served at /v1/systemone — and only uncertain answers reach the judge.
  • On 200 agent turns: threshold 0.7 sent 37% to the judge at 1.28 s and $2,997 per 1M checks, versus 2.59 s and $7,751 for Sonnet 4.6 alone.
  • The README reports 51% faster and 61% cheaper at threshold 0.7 with accuracy 0.695, against 0.675 for the judge alone.
  • Install with pip install grounded-ai for LLM judges (OpenAI, Anthropic, Bedrock) or pip install "grounded-ai[jev]" to add decision models.
  • MIT, 71 stars, 7 forks, Python, created 2024-06-14, last pushed 2026-10-16; a Colab notebook runs a full cascade.

Quickstart

python
from grounded_ai import CascadeEvaluator
from grounded_ai.backends.jev import HALLUCINATION, JevInput

cascade = CascadeEvaluator(
    decision_model="jev/jev-latest",
    judge="anthropic/claude-haiku-4-5",
    min_confidence=0.7,
)

Watch out

README reviewed 2026-10-17 and truncated mid-command in the Install block, so the decision-model extras and the full setup are not in the digest. The cascade timings, costs, and accuracies are the project's own benchmark on 200 agent turns against Claude Sonnet 4.6; no independent replication appears in the excerpt.

Questions about this entry

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Reactions & coverage

Posts, threads, and videos about this entry from around the web.

X: Microsoft-Decision-1 against Jev on a private eval

X: Vals AI's independent evaluation of Jev

X: An eval suite for System One models

X: Jev and Laya play chess instead of benchmarks

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