# POP3 SRV Record Lookup via DNS over HTTPS

> POP3 SRV Record Lookup via DNS over HTTPS is a paid API for AI agents from dns.intel.rallylive.ca, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-22).

Resolves _pop3._tcp SRV DNS records for a given domain using Cloudflare DoH, returning priority, weight, port, and target host for the domain's POP3 mail service.

## Facts

- Endpoint: GET https://dns.intel.rallylive.ca/dns/srv/pop3-tcp?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/pop3-srv-record-lookup-via-dns-over-https-bb5b531f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_liaGgtGQ1jPmq_PqGsgaj

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 pop3-srv-record-lookup-via-dns-over-https-bb5b531f
```

Example prompt: Can you look up the POP3 SRV record for example.com so I know what host and port their incoming mail service is running on?

## When to prefer this

Use this endpoint when you need to programmatically discover a domain's POP3 service configuration via DNS SRV records rather than guessing hostnames like 'pop.domain.com' or 'mail.domain.com'. Ideal for email client auto-configuration, infrastructure auditing, or verifying POP3 service endpoints before connecting. Prefer this over generic DNS tools when you specifically need SRV record fields (priority, weight, port, target) for the POP3 protocol.

## Known failure modes

- Domain has no _pop3._tcp SRV record — returns empty result or NXDOMAIN
- Invalid or malformed domain name input — returns error
- Cloudflare DoH upstream timeout — returns service unavailable
- Domain exists but POP3 SRV record not published — lookup returns no results
- Network failure reaching Cloudflare DoH resolver

## How this service works

POP3 service discovery (_pop3._tcp.<domain>): SRV records with priority, weight, port and target host, from Cloudflare DoH. Tells a client where the domain's pop3 service lives without guessing hosts. $0.01 per lookup.

## Output

Returns the SRV record details for _pop3._tcp.<domain> including priority (integer for server selection ordering), weight (load-balancing factor), port number (where POP3 listens), and target hostname, sourced from Cloudflare DNS over HTTPS. If no SRV record exists, returns an empty or error response.

## 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",
     "properties": {}
    }
   },
   "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/pop3-srv-record-lookup-via-dns-over-https-bb5b531f/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from dns.intel.rallylive.ca](https://www.zero.xyz/host/dns.intel.rallylive.ca/llms.txt)