UnFee — 1-Credit Base/ETH/XRPL RPC Gateway, True 0% Crypto Checkout & Form 8949 Tax Engine

xyz.unfee/mcpunfee.xyzstreamable-httpv1.4.0Scanned 1 hour ago

Flat 1-credit Base/ETH/XRPL RPC (eth_getLogs=1 credit, 250K free/mo), 0% crypto checkout & tax CSV.

12 tools: 2 do something that can't be undone, 6 change things and 4 only read.

Reads private data · 0
Reads text others write · 0
Can send data out · 1
No findings

Anlyon alternative

8 of these tools change something. Run those as governed actions.

Declare what an action changes, and Anlyon puts it under a shared limit, binds every approval to the exact request, and grades the outcome. It works on any HTTPS API you can describe as an action.

Anlyon does not run, proxy or govern this MCP server. A tool your own code calls directly is not routed through Anlyon and is not governed by it.

Import an OpenAPI spec →

Tools

Grouped by what each tool does, most consequential first. Open one for its reasons and full description; descriptions are the publisher's own words.

12 tools

Can't be undone 2Sends, pays, publishes or merges: once done, it cannot be taken back.Claude Code: ask

create_payment_linkCreate a zero-middleman-fee UnFee payment short link (/to/<wallet>/<amount>/<currency>), hosted checkout URL, dynamic OpenGraph social preview card, scannable SVG QR code, and 1-li…Can send data outNo findings
Why it is in this group
- The name "create_payment_link" says "create": a word for a change.
- The input carries an amount (input.amount) and a currency, so it moves money.
- The input addresses people (input.to): what it sends cannot be taken back.
What it can reach
- outboundThe input takes a destination (input.to): what the tool writes goes there.
Description, as the server wrote it
Create a zero-middleman-fee UnFee payment short link (/to/<wallet>/<amount>/<currency>), hosted checkout URL, dynamic OpenGraph social preview card, scannable SVG QR code, and 1-line HTML embed snippet for Base (USDC, ETH, cbBTC, EURC) or XRPL (XRP, RLUSD).
unfee_pay_with_delivery_proofExecute an atomic HTTP-200 Proof-of-Delivery x402 settlement check: settles payment ONLY if the seller returns HTTP 200..299 with a valid non-empty payload and matching SHA-256 dig…No findings
Why it is in this group
- The name "unfee_pay_with_delivery_proof" says "pay": a word that usually means money moves, which cannot be taken back.
Description, as the server wrote it
Execute an atomic HTTP-200 Proof-of-Delivery x402 settlement check: settles payment ONLY if the seller returns HTTP 200..299 with a valid non-empty payload and matching SHA-256 digest; drops authorization with $0.00 buyer charge if upstream fails.

Changes things 6Creates or changes something that can be changed back.Claude Code: ask

base_rpc_requestExecute any Base Mainnet (Chain ID 8453) JSON-RPC method (eth_call, eth_getLogs, eth_getBalance, eth_estimateGas, eth_sendRawTransaction, eth_blockNumber) at a flat 1 Request = 1 C…No findings
Why it is in this group
- The name "base_rpc_request" says "request": a word for a change.
Description, as the server wrote it
Execute any Base Mainnet (Chain ID 8453) JSON-RPC method (eth_call, eth_getLogs, eth_getBalance, eth_estimateGas, eth_sendRawTransaction, eth_blockNumber) at a flat 1 Request = 1 Credit (250,000 free calls/month, zero compute-unit multipliers).
ethereum_rpc_requestExecute any Ethereum Mainnet (Chain ID 1) JSON-RPC method (eth_call, eth_getLogs, eth_getBalance, eth_blockNumber, eth_estimateGas) at 1 flat credit per request (250,000 free calls…No findings
Why it is in this group
- The name "ethereum_rpc_request" says "request": a word for a change.
Description, as the server wrote it
Execute any Ethereum Mainnet (Chain ID 1) JSON-RPC method (eth_call, eth_getLogs, eth_getBalance, eth_blockNumber, eth_estimateGas) at 1 flat credit per request (250,000 free calls/month).
unfee_check_seller_reputationCheck a seller or x402 API provider on-chain/gateway Proof-of-Delivery reputation (verified HTTP-200 deliveries, dropped failed calls, delivery rate %, and buyer USD saved on faile…No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
Description, as the server wrote it
Check a seller or x402 API provider on-chain/gateway Proof-of-Delivery reputation (verified HTTP-200 deliveries, dropped failed calls, delivery rate %, and buyer USD saved on failed calls).
unfee_generate_tax_reportGenerate an instant IRS Form 8949, Schedule D summary, FIFO/HIFO/LIFO cost-basis calculation, non-taxable self-transfer reconciliation, and TurboTax / QuickBooks CSV export for any…No findings
Why it is in this group
- The name "unfee_generate_tax_report" says "generate": a word for a change.
Description, as the server wrote it
Generate an instant IRS Form 8949, Schedule D summary, FIFO/HIFO/LIFO cost-basis calculation, non-taxable self-transfer reconciliation, and TurboTax / QuickBooks CSV export for any Base (0x...) or XRPL (r...) wallet at $0.01 via x402 (or $0 on $5/mo Indie Tier), undercutting Koinly and CoinTracker by 99.9%.
verify_transactionVerify an on-chain Base Mainnet or XRPL transaction hash and return settlement confirmation details.No findings
Why it is in this group
- Nothing in its name or description says what it does, so it is counted as a write.
Description, as the server wrote it
Verify an on-chain Base Mainnet or XRPL transaction hash and return settlement confirmation details.
xrpl_rpc_requestExecute any native XRP Ledger (XRPL Mainnet) JSON-RPC method (account_info, book_offers, server_info, tx, submit, account_lines) at 1 flat credit per request with zero compute-unit…No findings
Why it is in this group
- The name "xrpl_rpc_request" says "request": a word for a change.
Description, as the server wrote it
Execute any native XRP Ledger (XRPL Mainnet) JSON-RPC method (account_info, book_offers, server_info, tx, submit, account_lines) at 1 flat credit per request with zero compute-unit markups.

Only reads 4Looks things up and changes nothing.Show 4 read-only tools

compare_payment_feesCompare legacy card processor fees (2.9% + $0.30) against UnFee Starter ($0/mo, 0.005% = 5¢ per $1,000 micro-fee) and UnFee Indie ($5/mo, True 0% protocol fee).No findings
Why it is in this group
- The name "compare_payment_fees" says "compare": a word for reading.
Description, as the server wrote it
Compare legacy card processor fees (2.9% + $0.30) against UnFee Starter ($0/mo, 0.005% = 5¢ per $1,000 micro-fee) and UnFee Indie ($5/mo, True 0% protocol fee).
eth_getLogs_flat_rateQuery Base Mainnet (8453) or Ethereum Mainnet (1) eth_getLogs event logs at 1 flat credit per request (saving 75x–500x vs.No findings
Why it is in this group
- The name "eth_getLogs_flat_rate" says "get": a word for reading.
Description, as the server wrote it
Query Base Mainnet (8453) or Ethereum Mainnet (1) eth_getLogs event logs at 1 flat credit per request (saving 75x–500x vs. legacy compute-unit RPC gateways that charge 75–500 CUs per eth_getLogs call).
get_instant_free_rpc_keyMint a live UnFee API key with Free Tier credits (flat 1 request = 1 credit across eth_call, eth_getLogs, and XRPL JSON-RPC; 0 compute-unit multipliers).No findings
Why it is in this group
- The name "get_instant_free_rpc_key" says "get": a word for reading.
Description, as the server wrote it
Mint a live UnFee API key with Free Tier credits (flat 1 request = 1 credit across eth_call, eth_getLogs, and XRPL JSON-RPC; 0 compute-unit multipliers).
get_live_arb_opportunitiesScan all 9 live Base Mainnet 3-hop triangular flash-loan arbitrage loops (cbXRP, AERO, EURC, cbBTC, VIRTUAL, BRETT, DEGEN, MORPHO, WELL) and XRPL CLOB spreads.No findings
Why it is in this group
- The name "get_live_arb_opportunities" says "get": a word for reading.
Description, as the server wrote it
Scan all 9 live Base Mainnet 3-hop triangular flash-loan arbitrage loops (cbXRP, AERO, EURC, cbBTC, VIRTUAL, BRETT, DEGEN, MORPHO, WELL) and XRPL CLOB spreads.

This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.

Exfil surface

Which tools read private data, which read text someone else can write, and which can send data out. One of each is a path a prompt injection can use.

No private-data, untrusted-input, outbound path in this server alone: no tool is tagged private-data or untrusted-input.

Reads private data0: Reads files, mail, messages, databases, secrets, calendars or repositories.
Reads text others write0: Brings in text someone else can write: web pages, inbound email, messages, issues and comments.
Can send data out1: Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL.; create_payment_link

Other servers in the same agent add their own tools to these paths. Audit your whole setup to see them together.

Findings

Matches of fixed checks, with the text they matched.

No check matched anything in these tool definitions. That is not a safety guarantee.

History

Changes to its tool definitions and to its remote endpoint, newest first.

No change seen yet. Its tools are rescanned every day, and a remote endpoint is looked at once a week.

All changes to this server

Install

Pinned to version 1.4.0. Values in angle brackets are yours to fill in.

claude mcp add --transport http unfee https://unfee.xyz/mcp

claude mcp add --transport http unfee https://unfee.xyz/mcp

Run in a terminal.

Claude Code permissions

Allow the reads, ask before a change or a way out, deny the deletes. Paste into .claude/settings.json.

.claude/settings.json

{
  "permissions": {
    "allow": [
      "mcp__unfee__get_instant_free_rpc_key",
      "mcp__unfee__compare_payment_fees",
      "mcp__unfee__get_live_arb_opportunities",
      "mcp__unfee__eth_getLogs_flat_rate"
    ],
    "ask": [
      "mcp__unfee__create_payment_link",
      "mcp__unfee__verify_transaction",
      "mcp__unfee__unfee_check_seller_reputation",
      "mcp__unfee__unfee_pay_with_delivery_proof",
      "mcp__unfee__unfee_generate_tax_report",
      "mcp__unfee__base_rpc_request",
      "mcp__unfee__xrpl_rpc_request",
      "mcp__unfee__ethereum_rpc_request"
    ],
    "deny": []
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. A read that can send data out (it takes a URL, say) asks first too. It assumes the server is installed as unfee. Review it before you use it.

Capability tags behind 1 rule

mcp__unfee__create_payment_link outbound

Keep the decision: fail CI when the tools change, follow every change, or show a badge.

Pin in CI

Fail a build when the tools you reviewed are not the tools the server serves today.

curl -s "https://anlyon.dev/api/v1/servers/xyz.unfee/mcp/verify?hash=ba508312f609228a73466ab14d447665bc0207d7cab81e5375aa907eb35393fe" | jq -e '.changed == false'

Pinned hash ba508312f609, from Oct 26, 2026, 05:18 UTC.

Watch

Get told when its tools change: a new tool, a new description, a new class.

https://anlyon.dev/servers/xyz.unfee/mcp/changes.xml

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Badge

[![anlyon.dev](https://anlyon.dev/badge/xyz.unfee/mcp.svg)](https://anlyon.dev/servers/xyz.unfee/mcp)

Source: MCP Registry. Synced Oct 26, 2026, 05:17 UTC.