Inspect an example without sending it
Switch networks to compare the request bodies. Copying JSON does not execute it. Replace example identifiers with the values required by your own read-only test and send requests only to an endpoint you are authorized to use.
READ-ONLY EXAMPLE / eth_getBalance
{
"jsonrpc": "2.0",
"id": 1,
"method": "eth_getBalance",
"params": [
"0x0000000000000000000000000000000000000000",
"latest"
]
}Run the downloadable helper locally
The helper has no package dependencies. It reads its configuration from environment variables, allows only three fixed read methods, sets a timeout, and exits with a sanitized error if the request fails. It never prompts for wallet access.
Download the Node.js read helperexport RPC_URL="YOUR_HTTPS_RPC_ENDPOINT"
export NETWORK="solana"
# Optional: set RPC_AUTHORIZATION for your provider.
node rpc-read.mjsConfiguration
| Variable | Meaning |
|---|---|
RPC_URL | Your HTTPS endpoint, or an HTTP localhost node. |
NETWORK | ethereum, solana, or bitcoin. |
RPC_AUTHORIZATION | Optional Authorization header value, supplied only in your local environment. |
RPC_TIMEOUT_MS | Optional timeout between 1,000 and 60,000 milliseconds; default 10,000. |
What to add in a real application
Validate the specific result schema, compare the reported network to your expected configuration, and define precision handling for methods that return amounts. Add a reviewed retry policy only after you classify errors. The example intentionally avoids automatic retries.
See the security checklist and bounded recovery guide before turning the helper into shared application infrastructure.