Free Casper RPC (CSPR)

Common JSON-RPC errors

What you are most likely to hit calling this interface, and what to do about it.

-32700

Parse error. The request body was not valid JSON. Check that the body is serialised JSON and that Content-Type is application/json.

-32600

Invalid request. The JSON parsed, but it is not a well-formed JSON-RPC call. Include jsonrpc, method and id fields. A batch must be a non-empty array.

-32601

Method not found. This node does not expose the method you called. Check the spelling and the namespace, and confirm the method is in the list above for this network. Tracing methods in particular are not enabled everywhere.

-32602

Invalid params. The method exists but the arguments are wrong. Check argument order and types. Most EVM methods want hex-encoded quantities, and a block parameter such as latest or a hex height.

-32603

Internal error. The node failed while handling an otherwise valid request. Retry with backoff. If it persists on one method, it is usually that method rather than the node.

-32000

Server error. A catch-all the node uses for execution failures, most often a reverted call or a request over a limit. Read the accompanying message. Execution reverted means your call failed on chain, not in transport. Narrow the block range if you are querying logs.

HTTP 429

Rate limited. You have exceeded the free tier request allowance. Back off and retry, batch reads into single calls, or move to a dedicated endpoint for production traffic.

HTTP 413

Payload too large. The request body exceeded what the node accepts. Split large batches into smaller ones.