# SiteCheck Web Intel – Barracuda Reputation Block List Lookup

> SiteCheck Web Intel – Barracuda Reputation Block List Lookup is a paid API for AI agents from api.webintel-api.workers.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-24).

Checks an IPv4 mail-sending address against the Barracuda Reputation Block List (BRBL) via public DNS and returns whether the IP is listed and what response code it received.

## Facts

- Endpoint: GET https://api.webintel-api.workers.dev/api/security/barracuda-reputation?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-24
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/sitecheck-web-intel-barracuda-reputation-block-list-lookup-36651422
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_aS9ylfhDgtg6uaywXqq94

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability sitecheck-web-intel-barracuda-reputation-block-list-lookup-36651422
```

Example prompt: Can you check whether the IP address 198.51.100.42 is listed on the Barracuda Reputation Block List — I need to know if it's flagged as a spam sender before we use it for outbound email?

## When to prefer this

Use this endpoint when you need a fast, DNS-based check of a specific IPv4 address against the Barracuda Reputation Block List specifically — ideal for email deliverability pre-flight checks, spam source investigation, or automated infrastructure vetting. Prefer it over generic IP reputation APIs when Barracuda BRBL coverage is specifically required. Note it does not cover domain reputation or other blocklists.

## Known failure modes

- Invalid or non-IPv4 input returns an error or no result
- IPv6 addresses are not supported by this endpoint
- Transient DNS failures may produce false negatives — retry recommended
- The list is point-in-time; a recently listed or delisted IP may not reflect the current state immediately
- No domain-level reputation is returned — only IPv4 addresses are checked

## How this service works

Checks an IPv4 mail-sending address against the Barracuda Reputation Block List (b.barracudacentral.org) through public DNS. Listed addresses return a 127.0.0.x code; unlisted ones return no record. The list is updated continuously, so this is a point-in-time answer. Domain reputation is not covered.

## Output

Returns whether the queried IPv4 address is listed on the Barracuda Reputation Block List. If listed, includes the 127.0.0.x DNS response code indicating the listing type. If unlisted, returns no record. This is a point-in-time result reflecting the continuously updated BRBL.

## Request schema (JSON Schema)

```json
{
 "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",
     "required": [
      "ip"
     ],
     "properties": {
      "ip": {
       "type": "string",
       "description": "IPv4 address such as 127.0.0.2 (test entry) or a sending IP (required)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/sitecheck-web-intel-barracuda-reputation-block-list-lookup-36651422/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.webintel-api.workers.dev](https://www.zero.xyz/host/api.webintel-api.workers.dev/llms.txt)