send

Build an unsigned transfer transaction (native or ERC-20).

Tier: Free

Parameters

ParameterTypeRequiredDescription
toAddressstringYesRecipient wallet address (0x…)
tokenstringYesToken to send — symbol (e.g. “ETH”, “USDC”) or contract address
amountstringYesAmount in human-readable units (e.g. “1.5” for 1.5 ETH)
chainIdnumberNoChain ID (default: 1)

The sender’s wallet address is resolved automatically from the Y0_API_KEY session — no need to pass it explicitly.

Example

"Send 0.5 ETH to 0x1234... on Ethereum"

Signing Flow

  1. MCP server calls signing service /api/build/send
  2. Signing service builds unsigned transfer (native or ERC-20 transfer())
  3. Unsigned tx queued for approval
  4. User reviews recipient, amount, and signs

Notes

  • Native transfers: simple value tx
  • ERC-20 transfers: encoded transfer(to, amount) calldata via viem