Genesis402

Screen address against sanctions lists

genesis402_screen_sanctions

Screen a crypto address against OFAC SDN, scam blocklists, and fraud registry to flag counterparties on published lists. Returns matches, sources, and evidence hash.

Instructions

Paid ($0.008 USDC). List lookup for one address on any chain against OFAC SDN digital-currency entries, community scam-address blocklists and the Blockchain Fraud case registry. Use as a fast, cheap first gate on a counterparty address. For balances plus sanctions plus a summary on an EVM address use genesis402_wallet_brief. Returns whether any list matched, and for every list consulted its dataset name, fetch URL and entry count, plus an evidence hash. A hit means the address appears on a published list; absence from every list is not a clearance. Not a compliance decision, not a finding about any person, not legal advice. Payment: call once without payment_signature to get the exact price quote (nothing is charged or signed), then call again with the signed payment to receive the result and settlement details.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "address": "<address>"
    },
    "name": "genesis402_screen_sanctions"
  }
}

Input Schema

Name	Required	Description	Default
`address`	Yes	The crypto address to screen, on any chain, exactly as written on that chain (4 to 120 characters, no spaces).
`payment_signature`	No	Optional. An x402 v2 payment you signed for this call's quote (the PAYMENT-SIGNATURE header value). Omit to get the price quote first; nothing is charged without it.

Output Schema

Name	Required	Description
`mode`	Yes	QUOTE_ONLY: price quote only, nothing signed or charged. PAID: the call was paid and result holds the data. FREE: the endpoint answered without payment.
`paid`	Yes	true only when a payment was settled for this call.
`price`	No	The Base USDC quote. Present on QUOTE_ONLY and on PAID calls made by a local payer; null when the rail offered no Base USDC lane or the caller signed the payment.
`result`	No	PAID or FREE: the endpoint's JSON result.
`resource`	No	QUOTE_ONLY: the full URL of the paid resource.
`how_to_pay`	No	QUOTE_ONLY: how to sign and resend the call.
`settlement`	No	PAID: decoded PAYMENT-RESPONSE settlement (transaction hash, network, payer), or null if the rail sent none.
`what_you_get`	No	QUOTE_ONLY: the rail's description of what the payment buys.
`payment_required_b64`	No	QUOTE_ONLY: the raw base64 PAYMENT-REQUIRED header, to sign with any x402 v2 client.
`also_accepted_networks`	No	QUOTE_ONLY: every network the 402 challenge accepts.

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv0.3.4Sep 29, 2026

changedOutput schema / (root)

Previous value: -nullNew value: +{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "additionalProperties": false,
+  "properties": {
+    "also_accepted_networks": {
+      "description": "QUOTE_ONLY: every network the 402 challenge accepts.",
+      "items": {
+        "type": "string"
+      },
+      "type": "array"
+    },
+    "how_to_pay": {
+      "description": "QUOTE_ONLY: how to sign and resend the call.",
+      "type": "string"
+    },
+    "mode": {
+      "description": "QUOTE_ONLY: price quote only, nothing signed or charged. PAID: the call was paid and result holds the data. FREE: the endpoint answered without payment.",
+      "enum": [
+        "QUOTE_ONLY",
+        "PAID",
+        "FREE"
+      ],
+      "type": "string"
+    },
+    "paid": {
+      "description": "true only when a payment was settled for this call.",
+      "type": "boolean"
+    },
+    "payment_required_b64": {
+      "description": "QUOTE_ONLY: the raw base64 PAYMENT-REQUIRED header, to sign with any x402 v2 client.",
+      "type": [
+        "string",
+        "null"
+      ]
+    },
+    "price": {
+      "anyOf": [
+        {
+          "additionalProperties": false,
+          "properties": {
+            "atomic": {
+              "description": "Price in USDC atomic units (6 decimals), as a decimal string.",
+              "type": "string"
+            },
+            "network": {
+              "description": "CAIP-2 network id of the lane, eip155:8453 (Base).",
+              "type": "string"
+            },
+            "payTo": {
+              "description": "Address the payment settles to.",
+              "type": "string"
+            },
+            "usd": {
+              "description": "Price in US dollars.",
+              "type": "number"
+            }
+          },
+          "required": [
+            "atomic",
+            "usd",
+            "payTo",
+            "network"
+          ],
+          "type": "object"
+        },
+        {
+          "type": "null"
+        }
+      ],
+      "description": "The Base USDC quote. Present on QUOTE_ONLY and on PAID calls made by a local payer; null when the rail offered no Base USDC lane or the caller signed the payment."
+    },
+    "resource": {
+      "description": "QUOTE_ONLY: the full URL of the paid resource.",
+      "type": "string"
+    },
+    "result": {
+      "description": "PAID or FREE: the endpoint's JSON result."
+    },
+    "settlement": {
+      "description": "PAID: decoded PAYMENT-RESPONSE settlement (transaction hash, network, payer), or null if the rail sent none."
+    },
+    "what_you_get": {
+      "description": "QUOTE_ONLY: the rail's description of what the payment buys.",
+      "type": "string"
+    }
+  },
+  "required": [
+    "mode",
+    "paid"
+  ],
+  "type": "object"
+}

Changed1 schema field changedv0.3.3Sep 29, 2026

changedInput schema / properties / address / description

Previous value: -"The crypto address to screen, as a string (4 to 120 characters)."New value: +"The crypto address to screen, on any chain, exactly as written on that chain (4 to 120 characters, no spaces)."

Changed2 schema fields changedv0.3.2Sep 26, 2026

addedInput schema / properties / address / description

Added value: +"The crypto address to screen, as a string (4 to 120 characters)."

changedInput schema / properties / payment_signature / description

Previous value: -"Optional. An x402 v2 payment you signed for this call's quote (the PAYMENT-SIGNATURE header value). Omit to get the price quote first."New value: +"Optional. An x402 v2 payment you signed for this call's quote (the PAYMENT-SIGNATURE header value). Omit to get the price quote first; nothing is charged without it."

First observedv0.3.1Sep 26, 2026

TDQS

A4.8/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Goes well beyond the sparse annotations (readOnlyHint=false, openWorldHint=true) by disclosing the price ($0.008 USDC), the two-call quote-then-pay flow, what 'nothing is charged or signed' means on the first call, settlement details on the second, and explicit limitations ('absence from every list is not a clearance', 'not a compliance decision'). It also describes the return contents (per-list dataset name, fetch URL, entry count, evidence hash), which the annotations do not cover.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the price and the core purpose, then usage, returns, caveats and the payment protocol in a logical order. It is dense and fairly long, but nearly every clause carries decision-relevant information; only minor trimming is possible.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given an output schema exists, return values need not be explained, yet the description still summarizes the shape (match flag, per-list metadata, evidence hash). For a paid, open-world lookup with caveats and a two-step payment handshake, nothing an agent needs to call it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3; the description adds real meaning on top by clarifying that the address can be on any chain, that the first call requires no payment_signature, and that the second call must carry the signed quote to obtain a result. It does not restate format details already in the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('List lookup for one address on any chain') plus the exact data sources (OFAC SDN digital-currency entries, community scam blocklists, Blockchain Fraud registry). It explicitly names the sibling it is not ('For balances plus sanctions plus a summary on an EVM address use genesis402_wallet_brief'), so an agent can distinguish it without opening either schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives a clear when-to-use ('fast, cheap first gate on a counterparty address') and names the specific alternative plus the condition that selects it (genesis402_wallet_brief for EVM balances + summary). It also states the call protocol: once without payment_signature for a quote, again with the signed payment.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.