Click on "Deploy Server".
Wait a few minutes for the server to deploy. Once ready, it will show a "Started" state.
In the chat, type @ followed by the MCP server name and your instructions, e.g., "@send21 Create a USDC pay link for 250 to carol@example.com"
That's it! The server will respond to your query, and you can continue using it as needed.
Here is a step-by-step guide with screenshots.
Remote Model Context Protocol server for send21 — non-custodial payment drafts and pay links.
send21 prepares payment instructions for BTC, USDC, USDT, and EURC. The payer signs in their own wallet. send21 never holds keys, never signs, and never broadcasts.
Live endpoint (Streamable HTTP): https://send21.io/mcp
Descriptor: https://send21.io/.well-known/mcp.json
Agent docs: https://send21.io/llms.txt
OpenAPI: https://send21.io/swagger/v1/swagger.json
Site: https://send21.io
Point an MCP client at the remote server:
{
"mcpServers": {
"send21": {
"url": "https://send21.io/mcp",
"transport": "streamable-http",
"headers": {
"Authorization": "Bearer s21_YOUR_API_KEY"
}
}
}
}Create scoped API keys at https://send21.io/api-keys (s21_…).
Scopes such as drafts:write, drafts:read, webhooks:manage cannot move funds.
tools/list works without authentication.
Related MCP server: coinvoyage-paykit
Typical tools (see live tools/list): create drafts / payment requests, fetch transaction templates, rates, and fee schedule. Signing and broadcast stay in the user’s wallet.
send21 — Direct. Non-custodial. Yours.
Contact: integration@send21.io
MIT
This server cannot be deployed
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