Docs - Faucet - BuildBear Labs

Fund wallets inside a BuildBear sandbox — drop native tokens (ETH, MATIC, etc.) or mint ERC-20 tokens to any address.

[!NOTE] Faucet commands only work on live sandboxes. Run buildbear status first if you are unsure.

faucet native

Fund native tokens to a wallet address.

buildbear faucet native [rpcUrl] --address <walletAddress> [options]

Arguments:

Argument	Required	Description
`rpcUrl`	No	BuildBear RPC URL. If omitted, reads from `.buildbear.json`

Options:

Flag	Type	Default	Required	Description
`--address <walletAddress>`	string	—	Yes	Wallet address to receive funds
`--amount <amountInEther>`	string	`1`	No	Amount in ether (e.g. `10`, `0.5`)
`--json`	flag	—	No	Output as JSON
`--quiet`	flag	—	No	Suppress output except errors

Examples:

# Fund 1 ETH (default) using .buildbear.json
buildbear faucet native --address 0xYourWalletAddress

# Fund 100 ETH to a specific address
buildbear faucet native --address 0xYourWalletAddress --amount 100

# Using an explicit RPC URL
buildbear faucet native https://rpc.buildbear.io/my-sandbox-id \
  --address 0xYourWalletAddress \
  --amount 10

# JSON output
buildbear faucet native --address 0xYourWalletAddress --amount 5 --json

Output:

✅ Sent 1 native tokens to 0xYourWalletAddress

JSON output:

{
  "result": null,
  "address": "0xYourWalletAddress",
  "amount": "1",
  "rpcUrl": "https://rpc.buildbear.io/my-sandbox-id"
}

faucet erc20

Mint ERC-20 tokens to a wallet address.

buildbear faucet erc20 [rpcUrl] --token <contractAddress> --address <walletAddress> [options]

Arguments:

Argument	Required	Description
`rpcUrl`	No	BuildBear RPC URL. If omitted, reads from `.buildbear.json`

Options:

Flag	Type	Default	Required	Description
`--token <contractAddress>`	string	—	Yes	ERC-20 token contract address
`--address <walletAddress>`	string	—	Yes	Wallet address to receive tokens
`--amount <amount>`	string	`1000`	No	Token amount (in token units, not wei)
`--json`	flag	—	No	Output as JSON
`--quiet`	flag	—	No	Suppress output except errors

Examples:

# Mint 1000 USDC (default amount) to a wallet
buildbear faucet erc20 \
  --token 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 \
  --address 0xYourWalletAddress

# Mint 50,000 USDC
buildbear faucet erc20 \
  --token 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 \
  --address 0xYourWalletAddress \
  --amount 50000

# With explicit RPC URL and JSON output
buildbear faucet erc20 https://rpc.buildbear.io/my-sandbox-id \
  --token 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 \
  --address 0xYourWalletAddress \
  --amount 1000 \
  --json

Output:

✅ Sent 1000 ERC-20 tokens (0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48) to 0xYourWalletAddress

JSON output:

{
  "result": null,
  "address": "0xYourWalletAddress",
  "token": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
  "amount": "1000",
  "rpcUrl": "https://rpc.buildbear.io/my-sandbox-id"
}

How it works

Both faucet commands use BuildBear custom RPC methods that bypass the normal blockchain rules inside a sandbox:

buildbear_nativeFaucet — directly sets the native balance of an address
buildbear_ERC20Faucet — mints ERC-20 tokens to an address without requiring the token owner's signature

These methods are only available on BuildBear sandboxes and will not work against public RPC endpoints.

Faucet

faucet native

faucet erc20

How it works

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