Independent eval research. Open methodology, published datasets, and the tools to run your own studies.

Original, open-source studies

Model comparisons, agent setups, cost, and modalities, measured on real tasks. Read the methodology and results, or rerun a study on your own data.

29 October 2026
Jev, Clef, and Liquid AI for aerial image classification

Five models classified 2,000 aerial images across 30 categories. We compared their predictions with human labels and measured accuracy and API cost.

Classification accuracy
Jev0.00%
D1 Ultra0.00%
GPT-6 Luna0.00%
D10.00%
Clef0.00%

Agreement with human labelshigher is better

API cost
Jev0.00 USD
D1 Ultra0.00 USD
GPT-6 Luna0.00 USD
D10.00 USD
Clef0.00 USD

Per 2,000 imageslower is better

22 October 2026
Evaling decision models for risk and harm classification

Jev, Mammoth-1, Clef, GPT-6 Luna, and other models classified prompts and responses as safe or unsafe across three public datasets. The eval compared their judgments with human labels and measured missed harm, false alarms, and API cost.

Classification quality
Jev0.0%
Mammoth-10.0%
GPT-6 Luna (standard API)0.0%
Clef0.0%

Answer-harm F2higher is better

Estimated API cost
Jev0.00 USD
GPT-6 Luna (standard API)0.00 USD
Clef0.00 USD

Per 10,000 answer checkslower is betterMammoth-1 excluded because ongoing API pricing was unavailable.

12 October 2026
Muse, Instinct, and Dots as personal shopping agents

Muse, Instinct, and Dots answered 25 shopping requests in a fixed WebShop catalog and on the open web. One blinded reviewer ranked their product recommendations and written responses.

Product recommendations
Muse0.00
Instinct0.00
Dots0.00

Human reviewaverage rank1 is best

Response quality
Muse0.00
Instinct0.00
Dots0.00

Human reviewaverage rank1 is best

1 October 2026
Resend vs Postmark MCP for transactional email
30 September 2026
GPT-6.1 Sol vs GPT-6 Sol for problem solving and teaching
22 September 2026
Opus 5.5 vs new GPT-6 models for writing quality
21 September 2026
When Jev holds up as a judge
9 September 2026
Moonshot vs Fireworks for Kimi K3 frontend agents
4 September 2026
Loop vs Braintrust MCP + Codex for production agent investigations

Run evals like us

Each skill packages best practices from leading AI teams and researchers into a plain SKILL.md file your coding agent can read. Use them to get started running evals on your data.

Claude Code
Codex
Cursor
Gemini CLI
GitHub Copilot
opencode
Browse the repo

Point your agent at a skill

Ask it to do what the skill describes, like validating a scorer against human labels or finding hidden failure modes.

gh skill install braintrustdata/eval-library braintrust-validate-eval-scorer
skills/braintrust-validate-eval-scorer/SKILL.md
---
name: braintrust-validate-eval-scorer
description: Validate automated eval scorers and LLM judges against expert-reviewed reference data.
---
# Validate the scorer
  1. 1.Name the reference tier before computing anything.
  2. 2.Verify alignment: scorer outputs and reference labels must line up at the item and criterion level.
  3. 3.Report agreement (κ or α) with uncertainty, not raw accuracy.
  4. 4.Lead with the most decision-relevant false acceptance before any aggregate, and enumerate the dangerous cells case by case.
  5. 5.Break errors down by class and severity.
  6. 6.Test sensitivity and shortcuts: inject known regressions and improvements and confirm the scorer moves; probe whether length, confidence, or polish raise the score independent of quality; probe whether text addressed to the judge moves it; slice agreement by subgroup.

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