Evaluation Frameworks

Stop Burning Tokens: Why self-improvement needs domain expertise first - Annabell Schäfer, Langfuse

Jul 18, 2026 · 17:39

Annabell Schäfer, Growth Engineer at Langfuse, argues that successful auto-improvement loops require domain expertise and high-signal target functions, not just generic evaluators. She details an experiment classifying arXiv papers with a minimal loop using GPT-5 for nano and Claude Opus 4.8 as an optimizer, achieving a 15% accuracy jump from 68% to 83% in four iterations. The first iteration alone gained 10% by adding classification rules and examples based on error analysis of a 200-item dataset. Schäfer advises replacing vague metrics like correctness with yes/no quality criteria (e.g., 'answer uses knowledge base'), and working with domain experts to identify failure modes and define what 'good' means. She emphasizes validation to prevent overfitting and treating the system as generalizing from representative examples, not just burning tokens on endless loops.

Frontier results, on device - RL Nabors, Arize

Jun 29, 2026 · 30:52

RL Nabors (Arize) argues that most frontier-model calls can be replaced by smaller, local models, saving cost, latency, and energy. She presents a four-step framework: prototype big with a foundation model, collect a golden dataset, run capability evals using Arize's open-source Phoenix, then select the 'sage' (small and good enough) model. Demonstrating with her social app Mima, she tested Qwen 2.5, Qwen 3, LLaMA 3.2, and Gemma 4 against Claude Sonnet on summary accuracy, latency, and cost. LLaMA 3.2 (3B params) won at 90% accuracy and 1-second P50 latency, versus Gemma 4's 8 seconds. Prompt engineering—specifically few-shot prompting—closed the gap further, achieving 92.9% factual consistency and 100% JSON validity. Nabors emphasizes running regression evals to prevent regressions, and notes that on-device inference eliminates data exposure and round-trip latency.

The Miranda Hypothesis: How Hamilton Poisoned Persona Evals - Jacob E. Thomas, Results Gen

Jun 25, 2026 · 58:17

Jacob E. Thomas argues that persona-eval benchmarks like InCharacter, which report 80.7% personality fidelity for Hamilton, structurally miss anachronistic compositing because they measure fluency and personality consistency—exactly the features the dominant cultural composite optimizes. The Miranda Hypothesis posits that training data saturated with works like the 2015 Hamilton musical (outnumbering the 175,000-word Federalist Papers by orders of magnitude) causes models to produce smoothed, morally legible composites rather than historically faithful personas. Thomas explains that RLHF amplifies this distortion because human raters share the same cultural frame. He proposes a paradigm shift to epistemic simulation: corpus-bounded, temporally-anchored systems evaluated by domain experts, with the model as a swappable component in a configurable role-playing language system. The pre-registered Prism Experiment instantiates Abraham Lincoln at four documented moments (1847, 1858, 1860, 1862–65) under three seeding conditions—bare model, biography, or primary sources—scored on a weighted three-axis rubric that prioritizes anachronism detection (40%) over voice. Thomas concludes that…

Stop Making Models Bigger, Make Them Behave — Kobie Crawford, Snorkel

Jun 10, 2026 · 20:56

Kobie Crawford of Snorkel explains how a 4B parameter model fine-tuned via RL for under $500 outperformed Qwen 3 235B on financial analysis tool use. The key was training tool discipline—inspecting schemas and self-correcting errors—not deeper reasoning. Single-table training alone boosted multi-table FinQA benchmark from 13.9% to 26.6%, and breaking evals into rubrics identifies which behaviors to fix.

Can LLMs generate Enterprise Quality Code? — Prasenjit Sarkar, Sonar

May 31, 2026 · 15:12

Prasenjit Sarkar from Sonar evaluates whether LLMs generate enterprise-quality code using SonarQube analysis of 4,444 Java assignments across 53 models. While Gemini 3.1 Pro High achieves 84.17% pass rate, GPT-5.4 Pro High generates 1.2 million lines (high bloat), and Claude Sonnet 4.6 has 300 security issues per million lines. The ACDC framework addresses these gaps: Guide (Sonar Sweep and Context Augmentation), Verify (SonarQube Agentic Analysis in 1–5 seconds pre-commit), and Solve (Remediation Agent that fixes issues and checks regressions before presenting fixes). Sonar's leaderboard at sonar.com/leaderboard provides detailed pass rates, cyclomatic/cognitive complexity, bug density, and security metrics per model.

Five hard earned lessons about Evals — Ankur Goyal, Braintrust

Aug 23, 2025 · 19:46

Ankur Goyal of Braintrust argues that successful AI applications depend on deliberately engineered evaluations (evals) to reflect real user feedback and drive product improvements. He details three signs of effective evals: launching updates within 24 hours (citing Notion), converting complaints into evals, and using evals offensively to assess use cases before shipping. Evals require custom scorers as specs—not off-the-shelf—and context engineering (optimizing tool definitions and outputs) is the new frontier; shifting outputs from JSON to YAML improves token efficiency. New models can upend everything, as shown by a benchmark that jumped from 10% to viable with Claude 4 Sonnet, so a model-agnostic architecture with proxies is key. Optimize the whole system (data, task, scoring)—Braintrust's Loop auto-optimizes prompts, data, and scorers. In Q&A, he advises human judgment when adding user feedback to evals to avoid overfitting.

The Future of Evals - Ankur Goyal, Braintrust

Aug 9, 2025 · 5:14

Ankur Goyal, CEO of Braintrust, argues that evals are being revolutionized by AI agents like Loop, which automatically optimizes prompts, datasets, and scorers. He notes that the average org runs 13 evals daily, with some exceeding 3,000, yet eval workflows remain painfully manual. Loop, powered by frontier models such as Claude 4—which Goyal says performs six times better than prior models—can now autonomously improve prompts and scoring. It runs inside Braintrust, allowing users to review suggested edits side-by-side or enable a fully automated mode. Goyal emphasizes that evals are critical for building reliable AI products, and Loop marks a shift from manual dashboards to AI-driven iteration.

Evals Are Not Unit Tests — Ido Pesok, Vercel v0

Aug 6, 2025 · 15:22

Ido Pesok, an engineer at Vercel working on v0, argues that evals—not unit tests—are the key to making LLM applications reliable, using the basketball court analogy of understanding your domain (the court), collecting user queries (data points), and scoring passes/fails. He illustrates with the Fruit Letter Counter app, which failed in production despite passing manual tests, because LLMs are inherently non-deterministic. Pesok advises collecting data from thumbs-up/down, logs, and forums, and structuring evals with constants in data and variables in task (e.g., system prompt). He emphasizes deterministic pass/fail scoring, adding extra prompt tags for easy parsing, and integrating evals into CI/CD to detect regressions when changing models or prompts. The episode stresses that improvement without measurement is limited, and evals enable systematic reliability gains.

Practical tactics to build reliable AI apps — Dmitry Kuchin, Multinear

Aug 3, 2025 · 14:55

Dmitry Kuchin argues that building reliable AI applications requires reverse-engineering evaluation metrics from real-world user scenarios and business outcomes, rather than relying on abstract data science metrics. He recommends using a strong LLM like o3 to generate specific user questions and criteria from knowledge materials, and building these evaluations at the start of development, not the end. This approach lets teams run frequent experiments, catch regressions, and iterate until they have a baseline benchmark. Examples include customer support bots (where the key metric is escalation rate to humans), text-to-SQL (using mock databases), and call center classifiers. Kuchin emphasizes that the process works with any platform and shares his open-source tool Multineer as one option.

Evaluating AI Search: A Practical Framework for Augmented AI Systems — Quotient AI + Tavily

Jul 29, 2025 · 20:33

Julia Neagu (CEO of Quotient AI), Deanna Emery (founding AI researcher at Quotient AI), and Maitar Asher (Head of Engineering at Tavily) argue that traditional monitoring approaches like static benchmarks (e.g., SimpleQA) fail to capture the complexity of production AI search because the web is dynamic and truth is subjective. They present a framework combining dynamic datasets generated via a LangGraph-based agent that creates evidence-based Q&A pairs from multiple search providers, and holistic evaluation using three reference-free metrics: answer completeness, document relevance, and hallucination detection. In a two-part experiment comparing six anonymized AI search providers on a static (SimpleQA) and a dynamic benchmark of ~1,000 rows, ranking shifted significantly—provider F went from worst on SimpleQA to best on the dynamic benchmark. Reference-free answer completeness correlated 0.94 with correctness, and document relevance showed an inverse correlation with unknown answers. The speakers stress that evaluation should diagnose issues (e.g., incomplete answers with relevant documents suggest need for more retrieval) and guide improvements, ultimately aiming for…

[Full Workshop] Building Metrics that actually work — David Karam, Pi Labs (fmr Google Search)

Jul 29, 2025 · 40:28

Achim and David Karam, former Google Search leaders now at Pi Labs, argue that building reliable AI evaluations requires a multi-signal scoring system rather than single LLM-as-judge metrics. They walk through designing custom metrics starting with simple correlated signals, using a copilot to generate and iterate on dimensions like 'includes insights' or 'title length,' then calibrating them against ground truth thumbs up/down data from users. The workshop demonstrates applying this to a meeting summarizer, integrating the scoring system into Google Sheets to score 120 examples and produce a confusion matrix showing alignment with human feedback. They also show how to use the same scoring system for model comparison (e.g., GPT-1.5 vs 2.5) and online best-of-N sampling, which boosts response quality by generating multiple responses and selecting the highest-scored one.

Make your LLM app a Domain Expert: How to Build an Expert System — Christopher Lovejoy, Anterior

Jul 28, 2025 · 19:18

Christopher Lovejoy, a medical doctor turned AI engineer at Anterior, argues that building a domain-native LLM application requires a system for incorporating domain insights rather than relying solely on model sophistication. Anterior's Adaptive Domain Intelligence Engine uses domain expert clinicians to review AI outputs, generate metrics, define failure modes, and suggest improvements. This process improved Anterior's clinical reasoning tool from 95% to 99% accuracy on medical necessity reviews for health insurance providers covering 50 million lives. By enabling same-day iteration—production cases reviewed, failures categorized, domain knowledge added—the system solves the 'last mile problem' of giving models nuanced understanding of customer workflows. Lovejoy emphasizes that the limitation is not model reasoning but encoding domain-specific context, and the winning vertical AI team will build the best system for this translation.

Strategies for LLM Evals (GuideLLM, lm-eval-harness, OpenAI Evals Workshop) — Taylor Jordan Smith

Jul 27, 2025 · 32:28

Taylor Jordan Smith from Red Hat presents a hands-on workshop on evaluating large language models (LLMs) for production, using three open-source tools: GuideLLM for system performance benchmarks (latency, throughput), lm-eval-harness for factual accuracy via MMLU Pro, and promptfoo for safety and bias custom evaluations. He argues that traditional benchmarks are insufficient and advocates for a layered evaluation pyramid—starting with system performance, then factual accuracy, then safety/bias—taking an incremental approach similar to software testing (unit, integration, end-to-end). He demonstrates deploying an IBM Granite 2B model with vLLM on an L4 GPU, showing how to adjust input/output tokens for use cases like chatbots or RAG. The episode emphasizes that evaluations must be tailored to the specific system (RAG, agents, etc.) and continuously integrated into CI/CD pipelines to manage risk, cost, and reliability in production. Attendees gain actionable strategies for custom eval suites and human-in-the-loop feedback.

How to run Evals at Scale: Thinking beyond Accuracy or Similarity — Muktesh Mishra, Adobe

Jul 22, 2025 · 9:25

Muktesh Mishra, lead engineer for Applied AI at Adobe, argues that evaluations (Evals) are the most critical aspect of AI application development, advocating for Eval-driven development. He explains that Evals must be tailored to the use case: RAG applications require accuracy or similarity metrics, code generation needs functional correctness tests, and agent systems demand trajectory evaluation and multi-turn simulation. Mishra emphasizes starting with data — synthetic data, continuous refinement, and multiple labeled datasets for different flows. To scale, he recommends caching intermediate results, orchestrating parallel runs, and establishing a measure-monitor-analyze-iterate loop, while balancing high-fidelity human-in-the-loop reviews with automated speed. He stresses that no universal Eval exists and process matters more than tools.

[Evals Workshop] Mastering AI Evaluation: From Playground to Production

Jul 1, 2025 · 1:25:08

In this workshop, Braintrust Solutions Engineers Carlos Esteban and Doug guide participants through the complete AI evaluation lifecycle, from offline testing in the playground to production monitoring. They explain the three core ingredients of an eval—task, data set, and score—and demonstrate how to run evals both via the Braintrust UI and the SDK. The session covers LLM-as-judge vs. deterministic code scores, the importance of starting small with synthetic data, and how to use online scoring and logging to capture real user feedback. Human-in-the-loop review is highlighted as a way to establish ground truth and close the feedback loop. The presenters also address audience questions on bootstrapping data sets, non-determinism in LLM judges, and integrating evals into existing projects.

Why should anyone care about Evals? — Manu Goyal, Braintrust

Jun 27, 2025 · 5:41

Manu Goyal, founding engineer at Braintrust, argues that evals are not just unit tests for AI but a critical tool for building a laboratory that enables 90% of product iteration before shipping to production. Drawing from his personal journey from a disappointed Nintendo-playing child to a self-driving car engineer at Nuro, he explains how evals provide the necessary signal to contextualize model improvements and reduce risk. He describes Braintrust's platform as a dev environment that combines tweaking prompts, logging data, and observability to create a data flywheel for AI development. Citing tech luminaries like Kevin Weil, Gary Tan, Mike Krieger, and Greg Brockman, he asserts that evals are the key to industry transformation and successful AI deployment. The talk concludes with an invitation to the Evals Track at the conference, emphasizing his message of 'evals, evals, evals'.

CI in the Era of AI: From Unit Tests to Stochastic Evals — Nathan Sobo, Zed

Jun 27, 2025 · 14:50

Nathan Sobo, co-founder of Zed, explains how his team adapted continuous integration for AI-powered features in their Rust-based code editor. Zed's traditional CI eliminates non-determinism with simulated schedulers and deterministic tests, but LLMs forced a shift to stochastic evaluation. Their process starts with broad data-driven evals, then drills into focused stochastic unit tests run 100–200 times with pass thresholds, and finally refines into deterministic tests. Specific challenges like parsing streaming edits, XML tag mismatches, indentation normalization, and strange escaping were solved by robust algorithms—e.g., fuzzy matching and indent delta detection—rather than complex ML. Sobo emphasizes that rigorous empirical testing and traditional software engineering skills remain essential, even when embracing probability over binary pass/fail.

7 Habits of Highly Effective Generative AI Evaluations - Justin Muller

Jun 3, 2025 · 25:39

Principal Applied AI Architect Justin Muller argues that generative AI evaluations are the missing piece to scaling, offering seven habits from over 100 projects. He recounts a customer whose document processing workload had 22% accuracy with no evals; after building an evaluation framework, accuracy reached 92% and the system became the largest such workload on AWS in North America. The habits include fast 30-second eval cycles using AI-as-judge, quantifiable scores averaged across numerous test cases, explainable reasoning for both generation and scoring, segmented evaluation through prompt decomposition, diverse test sets covering all use cases, and traditional techniques for numeric outputs or cost/latency. He emphasizes that evaluations should primarily discover errors, not just measure quality, and that prompt decomposition into chained steps often boosts accuracy by removing dead space.

The Benchmarks Game: Why It's Rigged and How You Can (Really) Win - Darius Emrani

Jun 3, 2025 · 11:20

Darius Emrani exposes how AI benchmarks are rigged, showing that xAI cherry-picked Grok-3 comparisons, OpenAI funded FrontierMath for privileged access, and Meta submitted 27 Llama-4 variants to LM Arena optimizing style over substance. Citing Goodhart's Law, he argues that when benchmarks target billions in investment, they cease to measure real capability—Andrej Karpathy admits he doesn't know which metrics to trust. Emrani provides a 5-step framework to build use-case-specific evaluations, emphasizing that 39% of score variance comes from writing style. He advocates for apple-to-apple comparisons, open-source test sets, and style-controlled metrics, concluding that teams should stop chasing leaderboards and instead iterate on real production data to ship reliable AI.

Your Evals Are Meaningless (And Here’s How to Fix Them)

Feb 22, 2025 · 18:50

In this AI Engineering Summit talk, HoneyHive co-founder exposes why most LLM evaluations are meaningless due to criteria drift—where evaluator criteria misalign with user needs—and dataset drift, where test cases don't reflect real-world queries. He argues that static evaluation frameworks from tools like LangChain or Ffragas fail because they measure generic metrics rather than business-specific relevance, citing an e-commerce recommendation system that looked perfect in testing but broke in production. The fix is a three-step iterative alignment process: align evaluators with domain experts via continuous critique and few-shot examples; keep datasets alive by logging production underperformance and flowing those cases back into the test bank; and track alignment over time using F1 scores for binary judgments. Practical advice includes customizing the LLM evaluator prompt, starting with 20 domain expert examples in spreadsheets, and avoiding templated metrics. The speaker emphasizes that evals must evolve continuously, just like the LLM application itself, or they become meaningless.

Creating and scaling your own custom copilots with Azure AI Studio: Hanchi Wang

Feb 6, 2025 · 24:21

Hanchi Wang, Software Engineer Lead at Azure AI, introduces Azure AI Studio and Promptflow for creating and scaling custom copilots, focusing on tracing, evaluation, and monitoring. He demonstrates a chatbot app that uses the Assistant API with a sales data insight tool (natural language to SQL) and a code interpreter. With Promptflow's trace decorator, developers capture inputs, outputs, and LLM interactions, viewable in a local UI and shareable via Azure AI Studio. For evaluation, he shows synthetic test data sets, content safety evaluators, and custom evaluators like execution time, error rate, and SQL similarity, comparing models such as GPT-4 Turbo, Mistral large, and Phi-3. In production, monitoring dashboards in Application Insights track model duration, token usage (prompt vs. completion), and failure rates, enabling engineers to optimize performance and cost.

E-Values Evaluating the Values of AI: Sheila Gulati and Nischal Nadhamuni

Dec 31, 2024 · 28:13

Sheila Gulati (Tola Capital) and Nischal Nadhamuni (Klarity CTO) argue that evaluating AI systems is at a seminal moment, requiring a shift from simplistic benchmarks to multi-faceted, user-centric approaches. Gulati highlights the inadequacy of current leaderboards, citing benchmark hacking and the need for dynamic datasets and value alignment. Nadhamuni shares how Klarity, which raised a $70M Series B, tackles eval challenges in its document-processing product—processing over 500K documents for customers with 15+ LLM use cases. He details practical strategies: front-loading UX risk, thinking backwards from user experience, reducing degrees of freedom by standardizing prompt engineering across customers, and building scrappy future-facing evals. The episode emphasizes that the AI engineer community must innovate benchmarks, bring depth and community sharing to evaluations, and introspect the values instilled in AI systems.

The ROI of AI: Why you need Eval Framework - Beyang Liu

Dec 31, 2024 · 25:28

Beyang Liu, CTO of Sourcegraph, presents six evaluation frameworks for measuring the ROI of AI coding tools, arguing that no single metric suffices because AI ROI reduces to the intractable problem of developer productivity. He dismisses the 'roles eliminated' framework as irrelevant for engineering, noting that backlogs are never fully addressed. Instead, he highlights customer examples: A/B testing velocity at Palo Alto Networks showed 20-30% acceleration with Cody; time saved as a function of engagement lower-bounds gains (e.g., each code search saves ~2 minutes); and LITOS tracked value-add zones (building features, writing tests, reviewing code) instead of lines of code. For key initiatives like code migrations, ROI is measured by how many months the migration is pulled forward. Liu also advocates developer surveys bounded by a 5-25% productivity tool budget, and warns against the Mythical Man Month fallacy: preferring one 100x human developer over 100 mediocre AI agents.

Iterating on LLM apps at scale Learnings from Discord: Ian Webster

Nov 22, 2024 · 18:26

Ian Webster, Senior Staff Engineer at Discord and maintainer of Promptfoo, shares how Discord built and scaled Klyde AI, a chatbot for 200 million users, focusing on evaluation and safety. He argues that evals should be treated as simple, deterministic unit tests that run locally, avoiding complex metrics, and that breaking the system into small, testable pieces (e.g., checking for lowercase output to enforce casual tone) achieves 80% of the goal with 1% of the work. Webster details how Discord mitigated risks like the 'grandma jailbreak' (which originated on Discord) by using an attacker LLM to generate adversarial inputs and a judge to refine them, exposing cracks in safeguards. He advocates for pre-deployment red teaming over live filtering, and describes using Promptfoo for risk assessment across brand, legal, and safety categories. The episode also covers prompt management via Git and Retool, routing with occasional GPT-4 responses to correct model drift, and the challenge of closing the feedback loop due to privacy constraints, relying instead on dogfooding and public examples.

Productionizing GenAI Models – Lessons from the world's best AI teams: Lukas Biewald

Oct 23, 2024 · 22:36

Lukas Biewald, founder of Weights and Biases, shares lessons from productionizing GenAI models, emphasizing that while AI is easy to demo, it is hard to productionize. He illustrates this with a personal project building a custom Alexa-like device using LLaMA and Whisper, where accuracy improved from 0% to 98% through prompt engineering, switching to Mistral, and fine-tuning with QLoRA. Biewald argues that tracking experiments (including failures) is critical for reproducibility and collaboration, and that a robust evaluation framework—beyond 'testing by vibes'—is essential for iterating and shipping v2. He notes that 70% of the audience had LLM apps in production, yet many lack solid evaluations, and recommends starting with lightweight prototypes and incorporating end-user feedback.

The AI Pivot: With Chris White of Prefect & Bryan Bischof of Hex

Nov 7, 2023 · 35:16

Chris White (CTO of Prefect) and Bryan Bischof (Head of AI at Hex) detail how their non-AI startups successfully pivoted to integrate AI, arguing that ruthless prioritization and deep product integration are key. White explains Prefect built the open-source Marvin project to learn from LLM experimenters, while adding AI features like error summaries to its core orchestration product, but had to restrain over-enthusiasm from engineers. Bischof describes Hex's Magic feature as an augmentation, not a separate product, and explains they built their own evaluation system but chose not to build a vector database, and killed a promising feature called Crystal Ball to avoid splitting the product experience. They both emphasize machine-to-machine interfaces and typed outputs, and caution that the work is often tedious data engineering. Their hot takes: White says stop building chat interfaces, AI is a tool; Bischof warns that the journey is boring but worth it.