{"uid":"cap_Bmy-XdpkY3eGIwkjj4oul","slug":"efnet-rbl-ipv4-dnsbl-lookup-a1314d17","name":"EFnet RBL IPv4 DNSBL Lookup","description":"Is this IPv4 address listed on efnet rbl (rbl.efnetrbl.org)? Performs the DNSBL query (reversed octets under rbl.efnetrbl.org, via Cloudflare DoH) and returns listed yes/no with the return codes and, where the list publishes one, the reason text. One list, one precise answer. $0.01 per lookup.","url":"https://ip.intel.rallylive.ca/ip/blacklist/efnet-rbl?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","properties":{}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_EohKCo5YaHK2vQSiqeiV0","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Checks whether an IPv4 address is listed on the EFnet RBL (rbl.efnetrbl.org) DNS-based blacklist, returning listed status, return codes, and reason text.","exampleAgentPrompt":"Can you check if 192.0.2.45 is listed on the EFnet RBL blacklist and tell me the reason code if it is?","exampleUseCases":[{"title":"Email server deliverability check","prompt":"Before I send our marketing campaign, check if our mail server IP 203.0.113.10 is listed on the EFnet RBL so I know if it might get blocked."},{"title":"Inbound connection abuse screening","prompt":"We're seeing suspicious traffic from 198.51.100.77 — can you check if that IP is on the EFnet RBL blacklist and what reason code it carries?"},{"title":"New hosting IP reputation audit","prompt":"We just got assigned 104.21.88.34 from our new hosting provider — can you verify it's not listed on the EFnet RBL before we start using it?"}],"resultDescription":"Returns a yes/no listed status for the queried IPv4 address on rbl.efnetrbl.org, along with the DNSBL return/response codes and, where published by the list, a human-readable reason text explaining why the address is listed.","failureModes":["Invalid or non-public IPv4 address returns an error or no result","DNS resolution failure via Cloudflare DoH causes a lookup error","IPv6 addresses are not supported (IPv4 only)","IP not listed returns a clean/not-listed result with no reason text","Temporary DNS timeout may cause intermittent failures"],"whenToPreferThis":"Use this endpoint when you specifically need to check an IPv4 address against the EFnet RBL (rbl.efnetrbl.org) DNS blacklist — for example when screening email senders, auditing new IP allocations, or filtering IRC/network abuse. Prefer it over generic reputation services when you need the precise EFnet RBL return codes and reason text for one specific list rather than an aggregated multi-list score.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-13T00:41:44.705Z","isFirstParty":false,"canonicalSlug":"efnet-rbl-ipv4-dnsbl-lookup-a1314d17"}