Claude Opus 4.6 Extended Reasoning Dataset: Traces for Better LLM Reasoning

The **Claude Opus 4.6 Extended Reasoning** dataset, created by TeichAI, is a small (<1 K records) JSON‑formatted collection of reasoning traces generated with Anthropic's Claude Opus 4.6. It aggregates distilled reasoning from several sources: Bullshit Bench for nonsense detection, legal and life‑decision scenarios for broader generalization, examples that illustrate how models handle vague or lazy prompts, and multi‑turn tool‑calling interactions.

Each entry follows a structured "messages" schema compatible with chat‑based pipelines. Non‑tool rows contain a system prompt, a user query, and an assistant reply that separates a `<think>` reasoning segment from the final answer. Tool rows extend this format with explicit `tool_calls` (e.g., a `web_search` function) and a subsequent `tool` response before the assistant produces a final answer. The dataset is licensed under Apache‑2.0 and can be loaded with the Hugging Face `datasets` library as well as pandas, polars, or mlcroissant.

Because the data captures both the internal thought process and external tool usage, it is valuable for fine‑tuning or evaluating large language models on chain‑of‑thought reasoning, tool‑augmented workflows, and robustness to ambiguous prompts. Its inclusion of legal and life‑decision contexts also makes it a useful testbed for alignment and interpretability research.