Returns pricing and payment details for a marketplace asset. Use this before purchasing to determine whether the asset is free or paid.

• Free assets: response contains isFree: true and basic asset metadata. You can download these directly via the marketplace URL.
• Paid assets: response contains isFree: false, asset metadata including sellerAddress and pricePerDownload, plus a full paymentRequirements object. Use the requirements to construct and sign an EIP-712 payment payload, then submit it to POST /v1/aion/marketplace/purchase.

Requires scope marketplace:read.

{
  "asset": {
    "uploadId": "up_a1b2c3d4e5f6g7h8",
    "title": "Public Dataset",
    "fileName": "data.csv",
    "mimeType": "text/csv",
    "sizeBytes": 12800
  }
}