All servers · Payments & accounting · Crypto & blockchain

Assay: settlement verification

io.fomox/assay · v1.0.0

Measured by MCP Station

Description written by the publisher, not verified

Verify crypto payments really settled and how much arrived. 20 chains. Read only, no API key.

Connect

claude mcp add --transport http assay https://fomox.io/api/assay/mcp

{
  "mcpServers": {
    "assay": {
      "url": "https://fomox.io/api/assay/mcp"
    }
  }
}

Tools as reported by the server

• verify_payment
  Check whether a crypto payment really settled and how much was ACTUALLY delivered, which is often not the amount the transaction claims. Use this before crediting anyone for an incoming payment. Returns `delivered` (what truly moved), `claimed` (what the transaction says), `mismatch` (true when they
• list_chains
  List every chain this service can verify, with the confirmation depth each needs before a payment is treated as final, and how deeply it can be verified. Call this if you are unsure whether a chain is supported or what to pass as `chain`.
• list_failure_modes
  List every known way a blockchain payment can appear successful while being worth less than it claims, or nothing at all. Each entry explains what the chain does, what it costs you when you get it wrong, and the one-line fix. Useful when writing or reviewing code that credits users for incoming cryp
• evaluate_spend_policy
  Check a proposed payment against spending limits that live OUTSIDE your context, where no instruction in a prompt, a message or a web page can change them. Returns a signed allow or deny with reasons. Use this before executing any transfer on behalf of a user. It enforces velocity caps, per-action c
• run_sandbox_case
  Practise on a payment designed to deceive you, with no money at risk. Returns a verification result shaped exactly like a real one for one of 19 adversarial cases. Decide whether you would credit it, then call check_sandbox_answer to find out whether you were right and what the mistake would have co
• check_sandbox_answer
  Score your decision on a sandbox case. Tell it whether you would have credited the payment and for how much, and it replies with whether that was correct and, if not, exactly what the error would have cost you in real units. This is the fastest way to find out whether your payment handling is actual

Website · JSON · Text for agents · Registry updated 2026-09-26