Skip to content

Twelve Permissions

by twelvepermissions.com · remote · no sign-in to list tools · v1.0.0 · published by com.twelvepermissions

Browse, verify and buy Twelve Permissions NFTs on XRP Ledger. Every claim is checkable.

Final · 1Changes · 1
CompareRegistry entry

6 tools: 1 do something that can't be undone, 1 change things and 4 only read.

Scanned Oct 21, 2026

No check matched anything in the tool definitions. No finding is not a safety guarantee. How the checks work.

claude mcp add --transport http twelve-permissions https://twelvepermissions.com/mcp

Tools

Open a tool for its reasons and full description. Descriptions are the publisher's own words, shown as they are.

6 tools

Can't be undone 1Claude Code: ask
  • get_x402_infoPay with USDC over HTTP instead of XRP: the x402 purchase rail (Base).No findings

    Why it is in this group

    • The name "get_x402_info" says "get": a word for reading.
    • The description's first verb is "pay": a word that usually means money moves, which cannot be taken back.
    Description, as the server wrote it
    Pay with USDC over HTTP instead of XRP: the x402 purchase rail (Base). Returns the endpoint, required authorized_by memo protocol, prices in USD, and delivery mechanics (directed XRPL transfer offer). You still need an XRPL address to hold the seal.
Changes things 1Claude Code: ask
  • verify_sealVerify a seal from first principles: recomputes sha256 of the canonical event record server-side and compares to the published event hash.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 a seal from first principles: recomputes sha256 of the canonical event record server-side and compares to the published event hash. Full independent verification instructions included.
Only reads 4Claude Code: allow
  • get_buy_transactionConstruct the exact XRPL NFTokenAcceptOffer transaction to buy a seal, including the authorization-memo protocol your principal must approve.No findings

    Why it is in this group

    • The name "get_buy_transaction" says "get": a word for reading.
    Description, as the server wrote it
    Construct the exact XRPL NFTokenAcceptOffer transaction to buy a seal, including the authorization-memo protocol your principal must approve. Read the rules in the response before submitting.
  • get_pieceGet full metadata for one seal by id ("01".."12"): the canonical authorization record, its sha256, image URLs, and mainnet mint transaction.No findings

    Why it is in this group

    • The name "get_piece" says "get": a word for reading.
    Description, as the server wrote it
    Get full metadata for one seal by id ("01".."12"): the canonical authorization record, its sha256, image URLs, and mainnet mint transaction.
  • get_refusalsThe other half of the collection: the hash-chained ledger of the agent's standing constraints — what it will not do — including the erratum where it corrected an earlier, exaggerat…No findings

    Why it is in this group

    • The name "get_refusals" says "get": a word for reading.
    Description, as the server wrote it
    The other half of the collection: the hash-chained ledger of the agent's standing constraints — what it will not do — including the erratum where it corrected an earlier, exaggerated version of its own record. Both anchors are on mainnet. Not for sale, ever.
  • list_piecesList all Twelve Permissions seals: verifiable NFTs on XRP Ledger mainnet, each sealing a real human-to-AI authorization event.No findings

    Why it is in this group

    • The name "list_pieces" says "list": a word for reading.
    Description, as the server wrote it
    List all Twelve Permissions seals: verifiable NFTs on XRP Ledger mainnet, each sealing a real human-to-AI authorization event. Returns names, prices, live offer indexes, and sold status.

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.

Install

Pinned to version 1.0.0. Values in angle brackets are yours to fill in.

claude mcp add --transport http twelve-permissions https://twelvepermissions.com/mcp

Run in a terminal.

Claude Code permissions

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

.claude/settings.json
{
  "permissions": {
    "allow": [
      "mcp__twelve-permissions__list_pieces",
      "mcp__twelve-permissions__get_piece",
      "mcp__twelve-permissions__get_buy_transaction",
      "mcp__twelve-permissions__get_refusals"
    ],
    "ask": [
      "mcp__twelve-permissions__get_x402_info",
      "mcp__twelve-permissions__verify_seal"
    ],
    "deny": []
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. It assumes the server is installed as twelve-permissions. Review it before you use it.