# AgentShelf CalDAV SRV DNS Lookup

> AgentShelf CalDAV SRV DNS Lookup is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-22).

Looks up SRV records at _caldav._tcp.{hostname} for a given registrable domain, returning CalDAV server discovery information.

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/dns-srv-caldav?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentshelf-caldav-srv-dns-lookup-fec927be
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_TZYQpZUpURYcmioU13CQk

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 agentshelf-caldav-srv-dns-lookup-fec927be -d '<json body>'
```

Example prompt: Can you look up the CalDAV SRV DNS record for example.com so I can find the calendar server address?

## When to prefer this

Use this endpoint when an agent needs to programmatically discover a CalDAV server for a given domain via DNS SRV records, especially during calendar client auto-configuration or service validation workflows. It is purpose-built for the CalDAV SRV lookup pattern, avoiding the need for general DNS libraries or direct DNS queries.

## Known failure modes

- No SRV record exists for the given hostname (NXDOMAIN or empty answer)
- Hostname is malformed or exceeds 253 characters
- DNS resolution timeout or upstream DNS failure
- Domain exists but has no _caldav._tcp SRV record configured

## How this service works

Call when an agent needs SRV records at _caldav._tcp.{hostname} for CalDAV. The caller sends the registrable domain, not the underscored name. Exact $0.002 USDC. Prefer unpaid POST /v1/sandbox/dns-srv-caldav first.

## Output

Returns the SRV record fields from _caldav._tcp.{hostname}, including the target CalDAV server hostname, port number, priority, and weight, enabling clients to locate and connect to the correct CalDAV service.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "hostname": {
   "type": "string",
   "examples": [
    "example.com"
   ],
   "maxLength": 253,
   "minLength": 1,
   "description": "Public DNS hostname such as example.com. Not a URL, not an IP literal, and not a private name."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentshelf-caldav-srv-dns-lookup-fec927be/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentshelf.syntexa.ch](https://www.zero.xyz/host/agentshelf.syntexa.ch/llms.txt)