This repository is a lightweight, reference implementation of several standard LLM benchmarks (MMLU, GPQA, MATH, HumanEval, DROP, MGSM, SimpleQA, BrowseComp, HealthBench) developed by OpenAI. It provides a unified evaluation framework based on an `Eval` base class and `SamplerBase` that supports OpenAI Chat Completions API, Anthropic Claude API, OpenAI Responses API, and reasoning models (o1, o3, o4-mini). The main entry point is `simple_evals.py` which accepts command-line arguments to select models and evals, runs them, and outputs HTML reports and JSON metrics. The code is cleanly factored into per-benchmark modules, a shared utility module (`common.py`), and sampler adapters. The framework is designed for reproducibility of OpenAI's published benchmark numbers, with all data loaded from public Azure blob storage URLs. The repository is deprecated as of July 2025 and will not receive updates for new models or benchmarks, though it will continue to host reference implementations for HealthBench, BrowseComp, and SimpleQA.