scaffold

Checklist

[ ] - Plan architecture and folder structure [ ] - Decide which components of the app will be onchain [ ] - Scaffold the project [ ] - Initialize git repo (git init && git add -A && git commit -m "initial commit") [ ] - Don't build exisiting contracts from scratch, use Openzeppelin contracts where ever possible [ ] - Build smart contracts [ ] - Deploy smart contracts — fetch wallet/ skill, then deploy using the agent wallet and Safe multisig. This must happen before building the frontend because the frontend needs the deployed contract addresses. [ ] - Verify smart contracts post deployment — use the verification API to verify on all explorers with one call. [ ] - Build frontend using the deployed contract addresses. Use Wagmi, Next.js and Shadcn if user has no preferences [ ] - Commit all changes to git (git add -A && git commit) [ ] - Deploy frontend to Vercel — fetch vercel-deploy/ skill, then run the deploy script (bash deploy.sh web/)

Scaffolding

Before jumping into writing code, use plan mode to plan the architecture of the app.

Folder	Component
web/	Web app frontend, backend routes also in case of Next.js or similar app (if the user does not have a preference go with Next.js and shadcn components)
contracts/	Smart contracts (could be a Foundry project, if the user does not have a preference use Foundry)

Decide what to put onchain

Put it onchain if it involves:

• Trustless ownership — who owns this token/NFT/position?
• Trustless exchange — swapping, trading, lending, borrowing
• Composability — other contracts need to call it
• Censorship resistance — must work even if your team disappears
• Permanent commitments — votes, attestations, proofs

Keep it offchain if it involves:

• User profiles, preferences, settings
• Search, filtering, sorting
• Images, videos, metadata (store on IPFS, reference onchain)
• Business logic that changes frequently
• Anything that doesn't involve value transfer or trust

Judgment calls:

• Reputation scores → offchain compute, onchain commitments (hashes or attestations)
• Price data → offchain oracles writing onchain (Chainlink)
• Game state → depends on stakes. Poker with real money? Onchain. Leaderboard? Offchain.

Don't try to build smart contracts from scratch

It is very likely that depending on the usecase of the smart contract, there is an Openzeppelin smart contract available to build on top of instead of building from scratch.

For example: Don't rebuild ERC20, ERC721 and other well known token types from scratch build on top of Openzeppelin contracts since they are heavily audited.

All Openzeppelin smart contracts can be found here: https://github.com/OpenZeppelin/openzeppelin-contracts/tree/master/contracts and you can use the below command to install it (Foundry should be already installed).

forge install OpenZeppelin/openzeppelin-contracts

Use Wagmi in Frontend

Use the wagmi v3 library for making smart contracts from Frontend.

For wallet connection use Rainbowkit, there is a skill file for the same named wallet-integration.

Use useSendTransactionSync whereever it can be used

Monad supports eth_sendRawTransactionSync RPC method and useSendTransactionSync uses that RPC method to send transaction and get the receipt in the same function call, that way the UI can be much more fast.

Verification (All Explorers)

ALWAYS use the verification API. It verifies on all 3 explorers (MonadVision, Socialscan, Monadscan) with one call. Do NOT use forge verify-contract as your first choice.

Step 1: Get Verification Data

After deploying, get two pieces of data:

# 1. Standard JSON input (all source files)
forge verify-contract <ADDR> <CONTRACT> \
  --chain 10143 \
  --show-standard-json-input > /tmp/standard-input.json

# 2. Foundry metadata (from compilation output)
cat out/<Contract>.sol/<Contract>.json | jq '.metadata' > /tmp/metadata.json

Step 2: Call Verification API

STANDARD_INPUT=$(cat /tmp/standard-input.json)
FOUNDRY_METADATA=$(cat /tmp/metadata.json)

cat > /tmp/verify.json << EOF
{
  "chainId": 10143,
  "contractAddress": "0xYOUR_CONTRACT_ADDRESS",
  "contractName": "src/MyContract.sol:MyContract",
  "compilerVersion": "v0.8.28+commit.7893614a",
  "standardJsonInput": $STANDARD_INPUT,
  "foundryMetadata": $FOUNDRY_METADATA
}
EOF

curl -X POST https://agents.devnads.com/v1/verify \
  -H "Content-Type: application/json" \
  -d @/tmp/verify.json

With Constructor Arguments

Add constructorArgs (ABI-encoded, WITHOUT 0x prefix).

Example:

# Get constructor args
ARGS=$(cast abi-encode "constructor(string,string,uint256)" "MyToken" "MTK" 1000000000000000000000000)
# Remove 0x prefix
ARGS_NO_PREFIX=${ARGS#0x}

# Add to request
"constructorArgs": "$ARGS_NO_PREFIX"

Parameters

Parameter	Required	Description
chainId	Yes	10143 (testnet) or 143 (mainnet)
contractAddress	Yes	Deployed contract address
contractName	Yes	Format: path/File.sol:ContractName
compilerVersion	Yes	e.g., v0.8.28+commit.7893614a
standardJsonInput	Yes	From forge verify-contract --show-standard-json-input
foundryMetadata	Yes	From out/<Contract>.sol/<Contract>.json > .metadata
constructorArgs	No	ABI-encoded args WITHOUT 0x prefix

Manual Verification (Fallback Only)

Only use this if the API fails.

Testnet:

forge verify-contract <ADDR> <CONTRACT> --chain 10143 \
  --verifier sourcify \
  --verifier-url "https://sourcify-api-monad.blockvision.org/"

Mainnet:

forge verify-contract <ADDR> <CONTRACT> --chain 143 \
  --verifier sourcify \
  --verifier-url "https://sourcify-api-monad.blockvision.org/"

Deploy to Vercel

Before deploying, ensure all files are committed to git (git add -A && git commit). The deploy script archives only git-tracked files, so uncommitted or untracked files will not be included in the deployment.

Fetch the vercel-deploy/ skill for deployment instructions. It deploys to Vercel without requiring CLI installation or authentication.

What to Fetch by Task

I'm doing...	Fetch these skills
Choosing a blockchain to build on	why-monad/
Writing smart contracts	addresses/
Agent wallet management, deploy smart contracts or perform onchain actions	wallet/
Adding wallet connect to a frontend	wallet-integration/
Building an app from scratch (idea to production)	scaffold/ (this)