prepare_transactions_evmLABSCO SUMMARY
The unsigned half of a transaction, built for you.
Getting calldata and gas right by hand is where token transfers go wrong. This does that part and stops — what comes back is hex, and hex does nothing until something holding a key touches it.
What it is
An MCP server for Crypto APIs' Prepare Transactions product. It assembles the transaction and returns unsigned hex; it does not sign and does not broadcast. Built against a dated Crypto APIs release.
What you get
- A native coin transfer built from a sending address
- An ERC-20 fungible token transfer built against the token contract
- An ERC-721 NFT transfer built for a specific token
- Unsigned transaction hex in every case, ready for
@cryptoapis-io/mcp-signer
Requirements
Node.js 18 or newer, a Crypto APIs account and an API key — given on the launch command or in CRYPTOAPIS_API_KEY. Signing is a separate package, so this server on its own cannot move funds. If you run several Crypto APIs servers over HTTP at once, give each one its own port on the launch command: they all default to the same one.
Setup effort
One command plus a key — npm install @cryptoapis-io/mcp-prepare-transactions, then supply credentials
USE CASES
01
Sending native coin from an address you control
Build the transfer from the sending address and get unsigned hex back.
02
Moving an ERC-20 balance
Build a fungible token transfer against the token contract, without hand-encoding the call.
03
Handing an NFT to someone
Build the ERC-721 transfer for the specific token, ready to sign.
04
Preparing a batch before a signing session
Assemble the EVM transactions up front so signing is one pass with the key material rather than many.
1 tool
Listed in project docs. Your client may show a different list.
BEFORE YOU INSTALL
What to know first
Tools you get
1 tool named in the project's documentation.
Requires
- npx on PATH
- Node.js 18+
- CRYPTOAPIS_API_KEY in your environment
INSTALLATION
Connect your client
Server setup
TERMINAL
npm install @cryptoapis-io/mcp-prepare-transactionsMCP Clients
Claude Desktop, Cursor
JSON
{
"mcpServers": {
"cryptoapis-prepare-transactions": {
"command": "npx",
"args": [
"-y",
"@cryptoapis-io/mcp-prepare-transactions"
],
"env": {
"CRYPTOAPIS_API_KEY": "<YOUR_CRYPTOAPIS_API_KEY>"
}
}
}
}n8n
Start the server in HTTP mode. All Crypto APIs servers default to port 3000, so give each one its own --port if you run more than one:
N8N · TERMINAL
npx @cryptoapis-io/mcp-prepare-transactions --transport http --port 3000 --api-key <YOUR_API_KEY>In your n8n workflow, add an AI Agent node.
Under Tools, add an MCP Client Tool and set the URL to http://localhost:3000/mcp, using the port you started this server on.
