qm_buy
Returns the live 402 payment challenge for one purchase. The input is exactly one of: sku (a music SKU id from qm_catalog, $0.05–$299.00 USDC) or endpoint ('iss-pass' or 'summarize', $0.05 USDC each) with its params (lat/lon for iss-pass, url for summarize). Returns the rail's exact payment requirements (amounts in USDC smallest units — 6 decimals) in machine-readable form. Payment is USDC on Base via x402 v1. The tool makes no payments, handles no private keys, and holds no funds; signing and submission happen from the caller's own wallet, and the rail fulfills automatically after settlement. Example: {sku:'deep-focus-vol1'} returns the $9.99 challenge; {endpoint:'iss-pass', lat:30.5, lon:-97.8} returns the $0.05 challenge for those coordinates.
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| lat | No | Latitude for iss-pass (-90 to 90). | |
| lon | No | Longitude for iss-pass (-180 to 180). | |
| sku | No | Music SKU id from qm_catalog (exactly one of sku or endpoint). | |
| url | No | Public http(s) URL for summarize. | |
| endpoint | No | Data endpoint id (exactly one of sku or endpoint). |