All servers · Crypto & blockchain · Payments & accounting

send21

io.github.send21io/mcp · v1.7.0

Measured by MCP Station

Description written by the publisher, not verified

Crypto pay links and API for people and AI agents. BTC, Lightning, USDC, USDT, EURC, SOL, ETH.

Connect

claude mcp add --transport http mcp https://send21.io/mcp

{
  "mcpServers": {
    "mcp": {
      "url": "https://send21.io/mcp"
    }
  }
}

claude mcp add --transport http mcp https://send21.io/mcp/oauth

{
  "mcpServers": {
    "mcp": {
      "url": "https://send21.io/mcp/oauth"
    }
  }
}

Tools as reported by the server

• get_transaction_template
  Get the transaction template for an on-chain draft: every output to pay, plus walletcreatefundedpsbt arguments and a pay-to-many CSV on Bitcoin, or payment URIs (and calldata on EVM chains) on Solana, Ethereum, Base, Arbitrum and Polygon. The sender's own wallet funds, reviews and signs it; send21 c
• get_fee_schedule
  Get the public send21 fee schedule: tiered percent by payment size in USD, min/max fee, and dust limit. No authentication needed.
• create_payment_request
  Create a payment request / checkout pay link (you are the RECEIVER asking to get paid). Price in any of 161 fiat currencies; the payer opens the returned payPath, picks one of the offered currencies (rate locks then), and pays a single QR-scannable transfer straight to your address. On accounts with
• propose_receiving_address
  Propose an address for the owner to approve: one of the owner's own receiving addresses (for pay links) or the address of someone the owner pays (for drafts). It is saved unapproved and the owner gets an email. On accounts with the policy ApprovedOnly, API keys can only use approved addresses, and o
• get_account_status
  What stands between you and a live pay link: whether the owner's email is confirmed, the receiving-address policy, how many addresses are approved or waiting for approval, unsettled fees, your key's scopes, and the next steps. Requires scope drafts:read.
• list_address_book
  List the account's saved addresses (label, address, network, direction: Sending = recipients the owner pays, Receiving = the owner's own addresses). Requires scope addressbook:read.
• get_draft
  Get a payment draft by id, including amounts, fee, quote, and status. Requires scope drafts:read.
• submit_lightning_proof
  Confirm a paid Lightning draft with its proof of payment: the 64-character preimage the paying wallet shows after a Lightning payment. Needed for drafts with a pasted bolt11 invoice, and for Lightning addresses whose provider does not report payments. send21 checks that SHA-256 of the preimage equal
• create_account
  Create a send21 account for your human owner, without a key. The owner gets an email with a link to take the account over; until they do, nothing can be created. Returns a bootstrap API key ONCE (save it and send it as Authorization: Bearer on every later call; reconnect this MCP client with it). Th
• get_payment_request
  Get a payment request by id: status (Open/Completed/Cancelled/Expired), pay path, offered currencies, and the underlying draft once the payer committed. Includes changeSignals and changeNotes: what is unusual compared with the account's paid payments (new_address, new_asset, unusual_amount), the sam
• get_rate
  Get the current exchange rate for an asset in a fiat currency (rate = fiat units per 1 whole asset unit, with source provenance). Assets: Btc, Usdc, Usdt, Eurc, Sol, Eth. 161 ISO 4217 fiat currencies are supported. Requires an API key.
• create_draft
  Create a non-custodial payment draft (you are the SENDER paying a receiver address). Amount is either exact base units (sats for BTC, micro-units for stablecoins, lamports for SOL, gwei for ETH) via amountBaseUnits, or fiat-pegged via fiatCurrency+fiatAmount with the exchange rate locked at creation
• list_draft_quotes
  List every quote (rate lock) of a fiat-priced draft, oldest first. Quotes never change; a re-quote adds a new one with its own id. Each has a sha256 (RFC 8785 JCS + SHA-256). Requires scope drafts:read.
• get_draft_status
  Lightweight status snapshot of a draft: status (AwaitingPayment/Seen/Confirmed/Expired/Cancelled), paying txid, confirmations, and reviewState when a transfer with a different amount arrived (pending = needs the receiver's decision and the draft is not paid; accepted; rejected; unresolved = the draf

Tool changes

• 2026-10-21: get_transaction_template, get_fee_schedule, create_payment_request, propose_receiving_address, get_account_status, list_address_book, get_draft, submit_lightning_proof, create_account, get_payment_request, get_rate, create_draft
• 2026-10-16: get_transaction_template, get_fee_schedule, create_payment_request, list_address_book, get_draft, submit_lightning_proof, get_payment_request, get_rate, create_draft, list_draft_quotes, get_draft_status

Website · JSON · Text for agents · Registry updated 2026-10-22