crossmint-wallets

name: crossmint-wallets description: "Create and manage blockchain wallets for users, agents, and companies using Crossmint API. Supports EVM chains, Solana, and Stellar."

Crossmint Wallet Management

Create programmable wallets for users, AI agents, and treasury operations using the Crossmint API.

Setup

Requires API key in Doppler. The scripts will check for WALLET_API_KEY first (from your Doppler mao-mao/prd config), then fall back to CROSSMINT_API_KEY.

Get your API key from Crossmint Console and add it to Doppler:

doppler secrets set WALLET_API_KEY sk_staging_... --project mao-mao --config prd

Scripts

All scripts use Bun runtime. Each script asks for confirmation before executing API calls. Use -y or --yes to skip confirmation (for automation).

1. Create Wallet

Create a new smart wallet for an agent or user.

# Using Doppler (recommended - picks up WALLET_API_KEY automatically)
doppler run --project mao-mao --config prd --command 'bun scripts/create-wallet.ts'

# Create wallet with custom user ID
doppler run --project mao-mao --config prd --command 'bun scripts/create-wallet.ts --userId AGENT01'

# Create non-custodial wallet (for production)
doppler run --project mao-mao --config prd --command 'bun scripts/create-wallet.ts --signer evm-passkey-signer'

# Specify chain
doppler run --project mao-mao --config prd --command 'bun scripts/create-wallet.ts --chain base-sepolia'

# Skip confirmation prompt (for automation)
doppler run --project mao-mao --config prd --command 'bun scripts/create-wallet.ts --userId AGENT01 --yes'

2. Get Wallet

Retrieve wallet details by address or user ID.

doppler run --project mao-mao --config prd --command 'bun scripts/get-wallet.ts --address 0x1234...'
doppler run --project mao-mao --config prd --command 'bun scripts/get-wallet.ts --userId AGENT01'

3. Fund Wallet (Testnet)

Fund a testnet wallet with USDC for testing.

doppler run --project mao-mao --config prd --command 'bun scripts/fund-wallet.ts --address 0x1234... --amount 100'

4. Transfer Tokens

Transfer tokens from one wallet to another.

# Basic transfer (default: base-sepolia, USDC)
doppler run --project mao-mao --config prd --command 'bun scripts/transfer.ts --from 0x1234... --to 0x5678... --amount 10 --token usdc'

# ETH transfer on Sepolia (note: use "ethereum-sepolia" not "sepolia")
doppler run --project mao-mao --config prd --command 'bun scripts/transfer.ts --from 0x1234... --to 0x5678... --amount 0.01 --token eth --chain ethereum-sepolia --yes'

Important: Both wallets must be Crossmint-managed for transfers to work. Check with get-wallet.ts first.

Wallet Types

Signer Types

Supported Chains

Important: Use full chain names in API calls, not short names:

Full list: EVM chains (ethereum, base, polygon, arbitrum, optimism, avalanche) + testnets (-sepolia suffix), plus solana and stellar.

Gotcha: --chain sepolia will fail. Use --chain ethereum-sepolia.

Environment Variables

The scripts automatically use your Doppler secrets. Configured in mao-mao/prd:

WALLET_API_KEY=sk_staging_...       # Your Crossmint API key (from Doppler)
CROSSMINT_ENV=staging               # "staging" or "www" for production (optional)

Note: Scripts check for WALLET_API_KEY first (Doppler), then CROSSMINT_API_KEY (fallback).

Testing

Run unit tests:

bun test

Run E2E test (requires CROSSMINT_API_KEY):

bun tests/e2e.test.ts

The E2E test will:

1. Create a wallet with a unique test user ID
2. Retrieve the wallet by address
3. Retrieve the wallet by user ID
4. Fund the wallet with testnet USDC
5. Create a second wallet
6. Transfer tokens between wallets

API Reference

• Create Wallet
• Get Wallet
• Fund Wallet
• Create Transaction

Example: Agent Wallet Flow

// 1. Create wallet for agent
const wallet = await createWallet({ userId: 'AGENT_001' });

// 2. Fund wallet (testnet)
await fundWallet(wallet.address, 100);

// 3. Agent can now make purchases via Orders API

Quick Reference: Common Workflows

Check if a wallet is Crossmint-managed

doppler run --project mao-mao --config prd --command 'bun scripts/get-wallet.ts --address 0xYOURADDRESS --yes'

If it returns wallet details (Type, User, Created), it's Crossmint-managed. If error, it's external.

Transfer ETH on Sepolia (working example)

doppler run --project mao-mao --config prd --command 'bun scripts/transfer.ts \
  --from 0xc54f836CBb4299B828b696Ef56f42edd898b3486 \
  --to 0x289155723B5d8F685D49446b2d9a4F7Bfa7606E3 \
  --amount 0.01 \
  --token eth \
  --chain ethereum-sepolia \
  --yes'

Known Wallets