How to Check Whether One Address Is Blacklisted

Use isBlacklisted when you want to check one address and do not need the full transaction context:

import { findRegistryCell, fetchRegistryPayload, isBlacklisted } from "@ckb-firewall/sdk";

const { txHash, index } = await findRegistryCell(rpcUrl, registrySpec);
const registry = await fetchRegistryPayload(rpcUrl, txHash, index);

const blocked = isBlacklisted("0xababababababababababababababababababababab", [registry]);
console.log(blocked ? "Blacklisted" : "Clean");

isBlacklisted compares entries with expiresAt in the past against the current wall-clock time and treats them as inactive. It accepts multiple registry payloads and checks the union of all entries.

For type args, use isTypeArgsBlacklisted:

import { isTypeArgsBlacklisted } from "@ckb-firewall/sdk";

const blocked = isTypeArgsBlacklisted("0x...", [registry]);

For a full transaction check with structured error codes, use preflightCheck instead — see How to run a pre-flight check in TypeScript.