Evalt
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Hit your quality bar. Cut the AI cost.

Turn a recurring AI task into a tested production route. On the first call, Evalt builds and judges the test, searches prompts, few-shot examples, models, and reasoning levels, then serves the cheapest configuration proven to clear your quality bar.

Python packageevaltv0.10.20 · Python 3.10+
python3 -m pip install --upgrade https://evalt.onrender.com/python-sdk/dist/evalt-0.10.20-py3-none-any.whl
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.

Not the smartest model. The right model for this job.

Evalt rejects models that are too weak, then stops paying for extra intelligence once a cheaper route proves it can do the work reliably.

Lowest-cost route above every gate$2.13 / 1K calls
ConfigurationWeighted finalCost / 1KDecision
GPT-5.6 Luna · low83.3%$49.25Below gate
MiniMax M3 · low100%$9.86Passes, costs more
DeepSeek V4 · high83.3%$5.91Below gate
DeepSeek V4 · rewrite + medium66.7%$2.98Rewrite still fails
GPT OSS 120B · medium100%$2.30Passes, costs more
GPT OSS 20B · medium100%$2.13Selected
GPT OSS 20B · low83.3%$1.07Too inaccurate
Ling 2.6 Flash · none0%$0.002Too inaccurate
Did it clear the target?

Every route faces the same unseen final-test cases and the same 95% requirement.

Was it repeatable?

Repeated executions expose a route that passes once and fails the next time.

What regressed?

Hard rules can veto an attractive average score.

Can I inspect each result?

Open the exact case, model output, and decision behind every score.

What did it cost?

Live spend stays visible under a server-enforced cap.

Can I prove it later?

Export the prompt, frozen contract, results, and model labels.

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.

Ready to test a real task?

Start with a reviewable test. Leave with a route you can ship.