eth_getStorageAt

curl https://mainnet.base.org \
  -X POST \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getStorageAt",
    "params": ["0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913", "0x0", "latest"],
    "id": 1
  }'

curl https://mainnet.base.org \
  -X POST \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_getStorageAt",
    "params": ["0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913", "0x0", "pending"],
    "id": 1
  }'

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x0000000000000000000000000000000000000000000000000000000000000001"
}