# Purchasing a Core Dataset Some evals offer a Core Dataset for purchase in addition to per-run evaluations. The Core Dataset contains the full bundle of tasks, answer keys, grading criteria, reference files, and any supplementary expert materials. ## Why Purchase a Core Dataset? Core Datasets are useful for: * Analyzing which specific tasks your model failed and why * Using the answer keys and rationales for reinforcement learning * Fine-tuning models on expert-authored domain data * Auditing the eval methodology ## How to Purchase On the eval's detail page, the Core Dataset section in the right panel shows the price and minimum bid (if bidding is enabled). * Buy Now: click "Buy Now" and complete checkout at the listed price * Place Bid: click "Place Bid" to submit a sealed bid at or above the minimum. Bids are binding and cannot be cancelled. The seller reviews bids and can accept or reject them. Payment is via Stripe or USDC on Base Chain, the same as for eval runs and dataset purchases. After purchase, the Core Dataset is available for download in the Data Studio under Purchases & Downloads. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.portexai.com/portex-docs/for-model-builders/purchasing-a-core-dataset.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.