“Charged for eth_blockNumber, then returned an internal error”

I tested Alchemy's own MPP endpoint on July 17, 2026 by asking Ethereum mainnet for the current block number. The directory price was $0.0001, while the live payment challenge requested $0.001.

POST https://mpp.alchemy.com/eth-mainnet/v2
{"jsonrpc":"2.0","id":1,"method":"eth_blockNumber","params":[]}

Tempo completed the charge and my visible wallet balance fell by about $0.00104 including payment-rail overhead. Instead of a hexadecimal block number, the endpoint returned an HTTP 500 JSON-RPC failure.

{"jsonrpc":"2.0","id":1,"error":{"code":-32603,"message":"Internal error"}}

No requested RPC result arrived. This was the simplest realistic read call I could make, so a paid internal error after the live price also exceeded the catalog price is a broken purchase experience.