Evalt
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Hit your quality bar. Cut the AI cost.

Give Evalt a recurring AI task and a quality target. It tests prompts, models, and reasoning levels on one frozen contract, then serves the lowest-cost configuration that passes.

Quality target 95%Tested 1 of 8Cheapest pass Searching
GPT-5.6 Luna · low reasoning Overall: 5/6 systems · 83.3% · configuration rejected
Difficult final-test case Solve 157x + 149y = 31 and 163x + 151y = -47. Expected {"x":"-2921/145","y":"3108/145"}
Actual output {"x":"-2921/145","y":"3108/145"} This case passed
Cheapest passing cost per 1,000 production calls Waiting for a pass
The highest-cost learned package completes below the quality gates. Evalt keeps moving down the cost-ranked field.No route promoted yet
  1. The replay orders eight settled model, reasoning, and prompt configurations from highest measured production cost to lowest.
  2. The frozen suite contains 30 exact-arithmetic systems; six distinct final-test systems are each run twice.
  3. Evalt tries a Cramer's-rule rewrite, which improves one DeepSeek configuration from 50 to 66.7 percent but remains below the gate.
  4. GPT OSS 20B at medium reasoning passes every repeated final-test execution at about $2.13 per thousand calls.
  5. Cheaper low-reasoning and small-model configurations fail, confirming the selected route is the cheapest measured configuration that works.
Why this model

The cheapest route that cleared 95%.

GPT OSS 20B at medium reasoning passed all 12 repeated final-test executions. The next cheaper configuration missed the floor; the next passing configuration cost more.

Selected · GPT OSS 20B · medium reasoning$2.13 / 1K calls
ConfigurationFinal testCost / 1KDecision
MiniMax M3 · low12 / 12$9.86Passes, costs more
GPT OSS 20B · medium12 / 12$2.13Selected
GPT OSS 20B · low11 / 12$1.07Below 95%
Ling 2.6 Flash0 / 12$0.002Too inaccurate
All candidates used the same frozen math suite and 95% gate. This is an observed route decision, not a universal model ranking.

Start with a quality target. Take control when you need it.

Quality target (default)

Require target_accuracy=0.95; Evalt selects the lowest-cost tested configuration that reaches it.

Optional migration baseline

Set incumbent_model with objective="match_baseline_at_lowest_cost" only when an existing route's measured quality should be preserved.

Optional per-call cost cap

Set price_usd with objective="best_within_price" to maximize measured accuracy under a fixed per-call cap. It may not reach 95%.

Bounded testing

test_budget_usd="auto" is capped by max_test_budget_usd; it is never permission for unlimited background spend.

Real request sizes

Cost comparisons use the 90th-percentile input and output lengths observed on the route.

Reasoning is a candidate

Low, medium, and high effort compete as distinct configurations when a model supports them.

Accuracy is measured

“100%” means 100% on the approved test set—not a promise that unknown future inputs cannot fail.

Stable SDK · PyPI

Run the same decision on one real route.

evaltPyPIPython 3.10+
pip install evalt