# RelayShield Certificate Expiry Checker

> RelayShield Certificate Expiry Checker is a paid API for AI agents from api.relayshield.net, paid per call via x402, $0.05/call, status unknown (last checked 2026-09-14).

Checks the SSL/TLS certificate expiry status for a given domain, returning days remaining, risk level, and a renewal recommendation.

## Facts

- Endpoint: POST https://api.relayshield.net/v1/payg/cert-expiry
- Price: $0.05/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/relayshield-certificate-expiry-checker-d753a5ce
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Ld4Le4-LKBMg9hdCTmN61

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 relayshield-certificate-expiry-checker-d753a5ce -d '<json body>'
```

Example prompt: Can you check the SSL certificate expiry for mybusiness.com and tell me how many days are left, what the risk level is, and whether I need to do anything about renewal?

## When to prefer this

Use this endpoint when you need a quick, pay-per-call SSL certificate expiry lookup with a structured risk assessment and human-readable recommendation, particularly in agent workflows where periodic domain health checks are needed without standing up a full certificate monitoring service.

## Known failure modes

- Domain not found or unreachable — cert_found may be false with no expiry data
- Invalid domain format returns an error
- Certificate lookup timeout for slow-responding domains
- Domain has no SSL certificate configured — cert_found returns false
- Network error reaching the target domain

## How this service works

RelayShield Landing Site

## Output

Returns a JSON object with the domain, certificate issue date, expiry date, whether a certificate was found, days remaining until expiry, a risk level (e.g. LOW, MEDIUM, HIGH), and a human-readable recommendation about whether renewal action is needed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "domain": {
   "type": "string",
   "description": "Domain to check TLS certificate expiry for"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "data": {
   "domain": "acme.com",
   "issued_at": "2026-06-07T00:00:00+00:00",
   "cert_found": true,
   "expires_at": "2026-09-05T00:00:00+00:00",
   "risk_level": "MEDIUM",
   "days_remaining": 46,
   "recommendation": "Certificate renews in 46 days — no action needed yet, but confirm your renewal automation is configured."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/relayshield-certificate-expiry-checker-d753a5ce/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.relayshield.net](https://www.zero.xyz/host/api.relayshield.net/llms.txt)