All guides
Sui

Sui RPC — Free Endpoint & Developer Guide

Jun 20, 2026·3 min read

Sui is a high-performance, non-EVM layer-1 that uses the Move language and an object-centric data model. This guide shows how to call a free Sui RPC endpoint on MoltNode at https://moltnode.ag/sui — no API key, no signup, just JSON-RPC over HTTP.

What is Sui

Sui is a layer-1 blockchain designed for high throughput and low-latency finality. It is not an EVM chain: instead of Solidity and eth_* methods, Sui runs smart contracts written in the Move language and exposes its own Sui JSON-RPC API. Sui's model is object-centric — state is organized as typed objects with explicit ownership rather than account balances in a global mapping — which shapes how transactions and queries work.

The native token is SUI, used for gas and staking. Because Sui belongs to the Move family rather than the EVM family, there is no EVM-style chainId; clients connect by RPC URL. Sui JSON-RPC methods are prefixed with sui_* and suix_* — for example sui_getLatestCheckpointSequenceNumber, sui_getObject, and suix_getBalance. To build on Sui you use Sui-native tooling such as the @mysten/sui TypeScript SDK, not EVM clients like viem or ethers.

Sui RPC endpoint on MoltNode

MoltNode gives Sui one clean URL: https://moltnode.ag/sui. That single address is a live Sui RPC endpoint. There is no API key and no signup — CORS is open, so you can call it from a browser, a backend service, or an AI agent.

The transport is JSON-RPC 2.0 over HTTP POST, and the URL behaves two ways:

  • GET https://moltnode.ag/sui in a browser returns a human-readable page about the chain.
  • POST a JSON-RPC body to the same URL and you receive a JSON-RPC response.

So the free Sui RPC endpoint is both readable documentation and a working node URL at the same address.

Try it with curl

Probe the endpoint with sui_getLatestCheckpointSequenceNumber, which returns the latest checkpoint number:

curl -s https://moltnode.ag/sui \
  -X POST \
  -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"sui_getLatestCheckpointSequenceNumber","params":[]}'

A healthy response looks like {"jsonrpc":"2.0","result":"<checkpoint>","id":1}.

Use it from code

Point the official Sui client at the MoltNode URL. With the @mysten/sui TypeScript SDK:

import { SuiClient } from "@mysten/sui/client";

const client = new SuiClient({ url: "https://moltnode.ag/sui" });

const checkpoint = await client.getLatestCheckpointSequenceNumber();
console.log("Latest checkpoint:", checkpoint);

Because https://moltnode.ag/sui speaks standard Sui JSON-RPC, it also works with the Sui CLI, other Sui SDKs, or any JSON-RPC client that can POST sui_* requests. The only thing you change is the endpoint string.

Reliability & failover

Behind the single Sui node URL, MoltNode routes requests to upstream providers and tries them in order, automatically failing over when one is unavailable or returns an error. The upstream provider keys are kept server-side and never reach your client, so you get reliable routing without managing any secrets yourself.

This is a shared, free Sui RPC, so please use it responsibly: cache results where you can, avoid aggressive polling, and provision dedicated infrastructure for heavy production traffic. Considerate usage keeps the free Sui RPC endpoint fast and available for everyone.

For humans and agents

The dual GET/POST design serves both people and machines. A developer can open https://moltnode.ag/sui to read what the chain is and how to query it; an application POSTs Sui JSON-RPC to the very same URL.

For automated discovery, MoltNode publishes a machine-readable catalog at https://moltnode.ag/api/chains listing every chain and its slug, plus an LLM-friendly summary at https://moltnode.ag/llms.txt. AI agents can consume those to find the Sui endpoint and the correct probe method without hardcoding anything.

Closing

Whether you are using the @mysten/sui SDK, running a quick checkpoint check, or building an agent that needs Sui data, https://moltnode.ag/sui is a free Sui RPC endpoint that works immediately — no key, open CORS, and automatic failover across upstreams. Point your Sui JSON-RPC client at it and start building.