// GLOSSARY -- WEB3 INFRASTRUCTURE

What is JSON-RPC?

1 min read Updated

JSON-RPC is the protocol standard for communicating with Ethereum nodes — defining a set of methods for querying blockchain state, submitting transactions, and subscribing to events through structured JSON messages.

WHY IT MATTERS

JSON-RPC is how every application talks to Ethereum. Methods like eth_getBalance, eth_sendRawTransaction, and eth_call form the API that wallets, dApps, and agents use to interact with the blockchain.

The protocol is simple: send a JSON request with a method name and parameters, receive a JSON response with the result. This simplicity has made it the universal blockchain API standard, copied by virtually every EVM chain.

Most developers interact with JSON-RPC through libraries (ethers.js, viem, web3.py) that abstract the raw protocol into typed function calls. Direct JSON-RPC interaction is useful for debugging and custom tooling.

FREQUENTLY ASKED QUESTIONS

What are the most common JSON-RPC methods?
eth_getBalance (check balance), eth_sendRawTransaction (submit transaction), eth_call (read contract), eth_blockNumber (current block), eth_getLogs (query events).
Do I need to know JSON-RPC?
Most developers use libraries that abstract it. Understanding JSON-RPC helps with debugging, custom tooling, and understanding what your library does under the hood.
Is JSON-RPC the same on all chains?
All EVM chains use the same core JSON-RPC methods. Some chains add custom methods. Non-EVM chains (Solana, Bitcoin) have different RPC interfaces.

FURTHER READING

Enforce policies on every tool call

Intercept is the open-source MCP proxy that enforces YAML policies on AI agent tool calls. No code changes needed.

npx -y @policylayer/intercept
github.com/policylayer/intercept →
// GET IN TOUCH

Have a question or want to learn more? Send us a message.

Message sent.

We'll get back to you soon.