JSON-RPC 2.0
All Ethereum JSON-RPC APIs (Infura, Alchemy, local nodes, MetaMask) use JSON-RPC 2.0. You need to know the protocol to interact with EVM chains.
What It Defines
Stateless, transport-agnostic remote procedure call protocol using JSON. Request: {jsonrpc, method, params, id}. Response: {jsonrpc, result, id} or {jsonrpc, error, id}. Used by Ethereum nodes (eth_call, eth_sendRawTransaction, etc.) over HTTP and WebSocket.
Canonical (Normative)
Convenient (Practical)
The canonical publication point for finalized RFCs. If a protocol is standardized as an RFC, the RFC Editor text is the normative final reference. Published by the IETF, IRTF, IAB, and independent stream.
Related Specs
ERC-20 is the most widely deployed standard in the Ethereum ecosystem. Every DeFi integration, exchange, and wallet interacts with ERC-20 tokens constantly.
EIP-712 is the standard for secure off-chain message signing used in permit() flows, meta-transactions, and Sign-In with Ethereum. Prevents blind signing attacks.
JSON is the lingua franca of web APIs. RFC 8259 is short and worth reading once — it clarifies edge cases around numbers, encoding, and trailing commas.