# TLS Self-Signed Certificate Checker

> TLS Self-Signed Certificate Checker is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-02).

Checks whether a TLS endpoint's port-443 certificate issuer DN equals its subject DN, indicating a self-signed certificate

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/tls-self-signed?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/tls-self-signed-certificate-checker-1a15c7ea
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_9Y8J2ZXACassEoFFBnFBw

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 tls-self-signed-certificate-checker-1a15c7ea -d '<json body>'
```

Example prompt: Can you check if the TLS certificate on api.example.com is self-signed — specifically whether the issuer DN matches the subject DN on port 443?

## When to prefer this

Use this endpoint when you need a deterministic, programmatic check of whether a TLS certificate is self-signed (issuer DN == subject DN) without relying on an LLM or manual inspection. Prefer the unpaid sandbox endpoint at POST /v1/sandbox/tls-self-signed for testing; use this paid endpoint for production verification where reliability and a guaranteed response are needed.

## Known failure modes

- Host unreachable or connection timeout on port 443
- Invalid URL or hostname format
- Host does not support TLS on port 443
- Certificate parsing failure
- DNS resolution failure for provided hostname

## How this service works

Call when an agent needs whether the port-443 issuer DN equals the subject DN. Exact $0.001 USDC. Prefer unpaid POST /v1/sandbox/tls-self-signed first.

## Output

A boolean or structured result indicating whether the certificate's issuer DN equals its subject DN (confirming self-signed status), along with relevant certificate details such as the issuer DN and subject DN values extracted from the port-443 TLS handshake.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "maxLength": 2048,
   "minLength": 8,
   "description": "Public URL whose hostname is inspected. Provide url or host. Private targets are rejected."
  },
  "host": {
   "type": "string",
   "examples": [
    "example.com"
   ],
   "maxLength": 253,
   "minLength": 1,
   "description": "Public hostname such as example.com. The port and check are fixed by the SKU. Provide host or url."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/tls-self-signed-certificate-checker-1a15c7ea/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)