Getting Started

Connect to Obsidian

Network Details

Property	Value
Chain ID	421 (0x1a5)
RPC URL	https://rpc.obsidian.network
Block Explorer	https://explorer.obsidian.network

Add to Wallet

MetaMask:

1. Settings → Networks → Add Network

2. Enter details above

3. Save

Programmatic:

await window.ethereum.request({
  method: "wallet_addEthereumChain",
  params: [
    {
      chainId: "0x1a5",
      chainName: "Obsidian",
      rpcUrls: ["https://rpc.obsidian.network"],
      nativeCurrency: { name: "OBS", symbol: "OBS", decimals: 18 },
    },
  ],
});

Send Your First Message

Using ethers.js

import { ethers } from "ethers";

const provider = new ethers.JsonRpcProvider("https://rpc.obsidian.network");
const wallet = new ethers.Wallet(privateKey, provider);

// Create message
const payload = "0x" + Buffer.from("Hello Obsidian!").toString("hex");
const nonce = "0x" + Date.now().toString(16);
const chainId = "0x1a5";

// Sign it
const messageHash = ethers.keccak256(
  ethers.solidityPacked(["bytes", "uint256", "uint256"], [payload, nonce, chainId])
);
const signature = await wallet.signMessage(ethers.getBytes(messageHash));

// Send (free via SMQ - compute VDF first)
const result = await provider.send("eth_sendMessageBlob", [
  {
    from: wallet.address,
    data: payload,
    signature: signature,
    nonce: nonce,
    chainId: chainId,
  },
]);

console.log("Message hash:", result);

Using viem

import { createPublicClient, http } from "viem";

const client = createPublicClient({
  transport: http("https://rpc.obsidian.network"),
});

const result = await client.request({
  method: "eth_sendMessageBlob",
  params: [{ from, data, signature, nonce, chainId }],
});

Retrieve Messages

// Get messages from a block
const messages = await provider.send("eth_getBlockMessages", [
  {
    blockNumber: "0x1234",
  },
]);

// Get messages by sender
const myMessages = await provider.send("eth_getMessagesBySender", [
  {
    address: myAddress,
    fromBlock: "0x0",
    toBlock: "latest",
  },
]);

Next Steps

• RPC Reference — All available methods

• Code Examples — Copy-paste snippets

• Use Cases — Inspiration for your app