# x402 Web Tools – HTTP Reachability & TLS Checker

> x402 Web Tools – HTTP Reachability & TLS Checker is a paid API for AI agents from web.kagurazaka.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-29).

Checks whether an HTTPS URL is reachable, reports its HTTP status, redirect chain with timings, security headers, and TLS certificate details including expiry.

## Facts

- Endpoint: GET https://web.kagurazaka.dev/v1/http-check?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-web-tools-http-reachability-tls-checker-31f55124
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_1l5-aaL4CnaKAfSNGFz98

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 x402-web-tools-http-reachability-tls-checker-31f55124
```

Example prompt: Can you check if https://www.x402.org/ is reachable right now, and tell me the full redirect chain, HTTP status, and when the TLS certificate expires?

## When to prefer this

Choose this endpoint when you need a quick, structured health-check of a specific HTTPS URL covering reachability, redirect tracing, TLS certificate validity, and security header presence in a single call. Prefer it over generic HTTP fetch endpoints when you specifically need TLS expiry dates, redirect hop timings, or security header auditing without retrieving page content.

## Known failure modes

- URL is unreachable (DNS failure, timeout, connection refused) — returns reachable: false with reason
- Non-HTTPS URL provided — schema requires https:// URLs
- Malformed or missing URL parameter — 400-level error
- TLS handshake failure — reachable: false with TLS error detail
- Endpoint itself times out on very slow targets — may return partial or error response

## How this service works

Request an https URL and report whether it is reachable, its status, every redirect hop with timings, key and security headers (HSTS, CSP and others), and the TLS certificate with its issuer, the names it covers and the days until it expires. An unreachable URL is a result too, with the reason.

## Output

Returns a JSON object with: reachable (bool), HTTP status code, total round-trip time in milliseconds, final URL after redirects, number of redirect hops with per-hop timings, key security headers (HSTS, CSP, etc.), and TLS certificate info including issuer, validity end date, days remaining, and an expires_soon flag.

## 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": [
      "url"
     ],
     "properties": {
      "url": {
       "type": "string",
       "description": "https URL of the page"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "tls": {},
      "status": {},
      "total_ms": {},
      "final_url": {},
      "reachable": {},
      "redirects": {}
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "tls": {
   "issuer": "Let's Encrypt, E7",
   "valid_to": "2026-12-20T00:00:00.000Z",
   "days_left": 56,
   "expires_soon": false
  },
  "status": 200,
  "total_ms": 180,
  "final_url": "https://www.x402.org/",
  "reachable": true,
  "redirects": 1
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-web-tools-http-reachability-tls-checker-31f55124/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from web.kagurazaka.dev](https://www.zero.xyz/host/web.kagurazaka.dev/llms.txt)