send21
Crypto pay links and API for people and AI agents.
Connector by send21io · GitHub account verified by the MCP Registry
Install
Works with Claude Code, VS Code, Cursor, Windsurf. Read the repository before you give any tool access to your data.
npx agentmarket install connector/send21io-mcp
Asks which of your tools to add it to (Claude Code, Codex, Cursor, VS Code, Windsurf, Gemini CLI, Claude Desktop) and shows the change first. See https://agentmart.dev/cli.
Remote endpoints
https://send21.io/mcpRemote (HTTP)https://send21.io/mcp/oauthRemote (HTTP)
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About
Reviews
Write a reviewNo reviews yet. Installed it? Reviews come from verified installers only. How reviews work
Permissions
What this server can do and what it asks for, from its tool list and install config. Checked Oct 25, 2026.
- Tools
- 9 read · 5 write · 0 delete
- Secrets
- 1 (API keys, tokens or passwords)
- Install scripts
- Nothing to install (hosted)
- Runs as
- Hosted (remote endpoint)
Tools by what they do 14
From the running server's own tool list (tools/list) on Oct 25, 2026.
Read 9 · Look things up without changing anything.
get_account_statusget_draftget_draft_statusget_fee_scheduleget_payment_requestget_rateget_transaction_templatelist_address_booklist_draft_quotes
Write 5 · Create, change, send or run things.
create_accountcreate_draftcreate_payment_requestpropose_receiving_addresssubmit_lightning_proof
Secrets and settings it asks for
Secrets: values you paste in that let it act as you.
Authorization
Network hosts it talks to 1
send21.io· found in remote endpoint, install command
Tools (14)
As the server listed them on Oct 25, 2026. Descriptions are the server’s own words; hidden characters are shown as [U+…].
create_accountCreate send21 account for ownerCreate 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). The key can read, propose addresses and check get_account_status; it can create pay links only after the owner took the account over and approved a receiving address you proposed. Agents onboard themselves; humans approve where the money lands. If the email already has an account, ask the owner for an…
create_draftCreate payment draftCreate 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. Returns the draft incl. id, amounts, fee, and status. Funds move only when the sender signs in their own wallet. send21 never holds keys. On accounts with the policy ApprovedOnly the receiver must be an address the owner approved (422 address_not_approved otherwise). Requires scope drafts:write.
create_payment_requestCreate pay linkCreate 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 the policy ApprovedOnly (see get_account_status) every address must be one of the owner's approved receiving addresses; otherwise the answer is 422 address_not_approved and nothing is created (propose it with propose_receiving_address). Requires scope drafts:write.
get_account_statusGet account statusread-onlyWhat 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.
get_draftGet payment draftread-onlyGet a payment draft by id, including amounts, fee, quote, and status. Requires scope drafts:read.
get_draft_statusGet draft statusread-onlyLightweight 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 draft expired while undecided, the money is with the receiver). Cheap to poll. Requires scope drafts:read.
get_fee_scheduleGet fee scheduleread-onlyGet the public send21 fee schedule: tiered percent by payment size in USD, min/max fee, and dust limit. No authentication needed.
get_payment_requestGet pay linkread-onlyGet 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 same lines the payer sees on the pay page; empty when nothing is unusual. Requires scope drafts:read.
get_rateGet exchange rateread-onlyGet 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.
get_transaction_templateGet wallet payment instructionsread-onlyGet 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 contains no signing code. Not for Lightning drafts (pay their invoice). Requires scope drafts:read.
list_address_bookList address bookread-onlyList the account's saved addresses (label, address, network, direction: Sending = recipients the owner pays, Receiving = the owner's own addresses). Requires scope addressbook:read.
list_draft_quotesList draft quotesread-onlyList 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.
propose_receiving_addressPropose receiving addressPropose 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 only the owner can approve one, signed in to the send21 app with a passkey or authenticator code. No key can approve an address. Requires scope addressbook:write.
submit_lightning_proofSubmit Lightning payment proofConfirm 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 equals the invoice's payment hash; the draft then confirms within about 30 seconds. Requires scope drafts:write.
Signals
- Last release
- Oct 22, 2026 (7 days ago)
Details
- Registry name
io.github.send21io/mcp- Version
- 1.7.0
- Auth
- Bearer token, Auth not stated
- License
- License unknown
- Website
- send21.io/docs/mcp
- First seen
- Oct 24, 2026
- Last checked
- Oct 24, 2026
- Source
- Official MCP Registry
Cite this page
send21 MCP server. Agent Mart. https://agentmart.dev/connectors/send21io-mcp (last updated 2026-10-24)