Back to the catalog

send21

Non-custodial payment drafts/pay links for BTC, USDC, USDT, EURC. Never holds keys.

Open source Repository Open in the app JSON README (API)

About

Non-custodial payment drafts/pay links for BTC, USDC, USDT, EURC. Never holds keys.

Details

Kind
MCP servers
Topic
Finance & crypto
Publisher
send21io
Origin
official
Category
ferramentas
Transport
http
Version
1.0.0
Last push
2026-09-06T05:27:51Z
Repository state
ativo
License
MIT
Added
2026-09-06 06:00:46
Updated
2026-09-06 06:00:46
Origin id
io.github.send21io/mcp

README

# send21 MCP

Remote [Model Context Protocol](https://modelcontextprotocol.io/) 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

## Connect

Point an MCP client at the remote server:

```json
{
  "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.

## What the tools do

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.

## Brand

send21 — Direct. Non-custodial. Yours.  
Contact: integration@send21.io

## License

MIT

More