presign-guard

Is it safe to sign?

CommunityOnlineNo sign-inGlobalFreeRead-only

What it can do

    What data it sees

    Do you need an account

    No: the server works without sign-in

    Is it safe to sign? Checks agent transactions, permits, tokens and approvals: green/orange/red.

    How to connect

    How to connect presign-guard to Claude

    The server address to paste into Claude settings:

    https://presign-guard.fizzl.eu/mcp

    1. Open Claude (claude.ai or the desktop app).
    2. Go to Settings → Connectors.
    3. Click Add custom connector.
    4. Paste the server address copied below into Remote MCP server URL and click Add.
    5. In a chat, click + → Connectors and switch the new connector on.

    Custom connectors are available on Free, Pro, Max, Team and Enterprise plans (Free is limited to one). On Team and Enterprise an organization Owner adds the connector first under Organization settings → Connectors.

    Authorization

    After you click Add, a sign-in window for the service opens. Sign in with your own account and approve access. Claude never sees your password.

    How to connect presign-guard to ChatGPT

    The server address to paste into ChatGPT settings:

    https://presign-guard.fizzl.eu/mcp

    1. Open ChatGPT in a browser (chatgpt.com). A Plus, Pro, Business, Enterprise or Edu plan is required.
    2. Turn on developer mode once: Settings → Apps → Advanced settings → Developer mode.
    3. Open Settings → Connectors and click Create.
    4. Fill in the form: Name (anything), Description (one line about what the service does), MCP server URL (copy it below).
    5. Under Authentication choose OAuth if the service requires sign-in, otherwise None. Click Create.
    6. In a new chat open + → Apps/Connectors and enable the connector.

    OpenAI has renamed this section before (Connectors → Apps/Plugins). If the label differs, search settings for "developer mode". On Business/Enterprise workspaces an admin must allow custom connectors first.

    Authorization

    On first use ChatGPT opens the service's sign-in window. Sign in and approve access.

    How to connect presign-guard to Cursor

    The server address to paste into Cursor settings:

    https://presign-guard.fizzl.eu/mcp

    Fastest: click Open in Cursor below and confirm the prompt.

    Manually:

    1. In Cursor open Settings → Cursor Settings → MCP and click Add new global MCP server.
    2. Paste the JSON copied below into ~/.cursor/mcp.json (per project: .cursor/mcp.json in the repo root).
    3. Save the file. The server appears in the MCP list; authorize it there if asked.

    Authorization

    If the service needs sign-in, an authorize button appears next to the server in the MCP list.

    Server tool list (8)

    Raw names from tools/list. Only developers need these.

    presign_quick_checkFree: the green/orange/red verdict only, for a transaction, token approval, EIP-712 signature, XRP Ledger transaction (type xrpl) or Algorand transaction (type algorand) your agent is about to sign. Limited to 10 calls per hour. For the reason codes and details use presign_check ($0.01); for a plain-language explanation presign_check_explain ($0.03).
    token_quick_verdictFree: the green/orange/red verdict and grade only, for a Solana or EVM token your agent is about to buy, hold or accept. Limited to 10 free calls per hour (shared with presign_quick_check). For the reasons, one-line summary and market data use token_verdict ($0.01).
    presign_checkPaid ($0.01 USDC via x402 on Base or Solana): call this before you sign. Send the transaction, token approval or EIP-712 signature (Permit, Permit2, EIP-3009 x402 payment, Seaport) your agent is about to sign; get back green, orange or red with reason codes: who gets access, whether the spender or recipient is flagged, sanctioned (OFAC SDN) or unverified, unlimited allowances, and the token itself (honeypot, fake look-alike, high tax). On Solana (type solana, the base64 wire transaction): every instruction decoded and the transaction simulated (token account takeovers, System Assign, unlimited delegates, durable nonces, hidden owner or delegate changes). On the XRP Ledger (type xrpl, the unsigned tx JSON): account takeovers (SetRegularKey, SignerListSet, disabling the master key), fake RLUSD, partial payments, missing destination tags, trust-line and issuer risks, and DEX offers far below market. On Algorand (type algorand, base64 msgpack transaction or group in transactions): rekeys, closing the account or an asset to someone else, clawbacks, fake USDC, app update/delete/clear, simulated. Only proceed on green; on orange ask your user; never sign on red. Same as POST /v1/check. The answer carries a signed receipt (EIP-191, bound to your arguments) that proves later which verdict you got.
    presign_check_explainPaid ($0.03 USDC via x402 on Base or Solana): the same verdict and reason codes as presign_check, plus a 3 to 5 sentence plain-language explanation a person can read before approving (lang en or nl). Same as POST /v1/check/explain. The answer carries a signed receipt (EIP-191, bound to your arguments) that proves later which verdict you got.
    token_verdictPaid ($0.01 USDC via x402 on Base or Solana): call this before your agent buys, holds or accepts a token. Send the chain (solana, base, ethereum, arbitrum, optimism, polygon, bsc, xrpl, algorand) and the token address, mint, CURRENCY.rIssuer or Algorand asset id; get back green/orange/red, a grade (SAFE, CAUTION, RISKY, AVOID), reason codes (mint or freeze authority still active, honeypot, tax or transfer fee, LP not locked, low liquidity, new token, concentrated holders, rugged), a one-line summary, and market data (price, liquidity, market cap, 24h volume, age). Same as GET /v1/token. The answer carries a signed receipt (EIP-191, bound to your arguments) that proves later which verdict you got.
    wallet_approvalsPaid ($0.02 USDC via x402 on Base or Solana): audit the open token approvals of a wallet on an EVM chain (base, ethereum, arbitrum, optimism, polygon, bsc) or on Solana, for example your agent's own wallet as a periodic check. Get back green/orange/red, a grade, a one-line summary and every approval with its spender. EVM, every ERC-20 allowance: flagged malicious (red), a plain wallet, on a doubt list, an unverified contract or an unlimited allowance to a spender not on the GoPlus trust list (orange), with a revoke.cash link. Solana, every SPL token delegation (Approve): a delegate on the OFAC SDN list (red), a delegate that is a plain wallet or an unlimited delegation (orange), with the token account to revoke on; Token-2022 tokens with a permanent delegate are listed too. NFT approvals are not covered. Same as GET /v1/approvals. The answer carries a signed receipt (EIP-191, bound to your arguments) that proves later which verdict you got.
    screen_walletPaid ($0.01 USDC via x402 on Base or Solana): call this before your agent pays an address, or before accepting money from one. Send any chain's wallet address (EVM 0x..., Solana, Tron, Bitcoin, XRP Ledger, Algorand, or another currency OFAC lists). Get back green/orange/red: red SANCTIONED_ADDRESS with the SDN entry (name, programs, currency) when the address is on the OFAC SDN list, red or orange when GoPlus reports theft, phishing, laundering or mixer use (EVM). Never pay or accept funds on red. The answer carries a signed receipt (EIP-191, bound to your arguments) that proves later which verdict you got.
    feedbackReport a bug, a missing feature or anything else about this service, in a structured way. Free. A person reads every report; nothing is run or changed automatically.