# URL Preflight Check

> URL Preflight Check is a paid API for AI agents from agent.kihustle.tech, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-16).

Performs a fast, deterministic HTTP check on a public URL returning status code, redirect chain, content-type, response size, and page title before committing to deeper crawls.

## Facts

- Endpoint: POST https://agent.kihustle.tech/services/url-preflight/jobs
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/url-preflight-check-4e65512c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_6GYFomFc7BC3KIalhljzg

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 url-preflight-check-4e65512c -d '<json body>'
```

Example prompt: Before we start scraping, do a quick preflight check on https://example.com/landing-page — I just need to know if it's alive, what status code it returns, whether it redirects anywhere, and what the content-type and page title are.

## When to prefer this

Use this endpoint as a cheap gate ($0.01) before investing in deeper, more expensive crawls or content extraction. Ideal when you need to confirm a URL is alive, check its final destination after redirects, or gate on content-type before attempting to parse. Choose this over full scraping endpoints when you only need HTTP-level metadata and don't need page content or structured extraction.

## Known failure modes

- URL is unreachable or times out — returns error status and no content metadata
- URL returns non-2xx status (e.g. 404, 403, 500) — status code returned but content fields may be empty
- Malformed or non-public URL provided — likely returns validation error
- URL is behind authentication or firewall — may return 401/403 with no content
- Redirect loop detected — may return error or partial redirect chain

## How this service works

Fast deterministic check that a public URL is alive: HTTP status, redirects, content-type, size, and title. Built for agent workflows before paying for deeper crawls.

## Output

Returns HTTP status code, any redirect chain (intermediate and final URLs), content-type header, response body size in bytes, and extracted page title — all from a single lightweight HEAD/GET probe of the target URL.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "description": "Public https URL to preflight"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "alive": true,
  "bytes": 12500,
  "title": "Example Domain",
  "job_id": "job_example",
  "status": "completed",
  "service": "url-preflight",
  "sources": [
   {
    "url": "https://example.com/",
    "note": "preflight"
   }
  ],
  "summary": "URL alive (HTTP 200); no redirect; title=set. Preflight complete for agent workflow gating.",
  "final_url": "https://example.com/",
  "next_jobs": [
   {
    "url": "https://agent.kihustle.tech/services/aeo-readiness/jobs",
    "why": "Deeper agent-surface / AEO readiness audit",
    "service_id": "aeo-readiness"
   }
  ],
  "redirected": false,
  "issue_codes": [],
  "limitations": [
   "Single GET; no JS render; private IPs blocked."
  ],
  "status_code": 200,
  "content_type": "text/html",
  "generated_at": "2026-01-01T00:00:00+00:00"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/url-preflight-check-4e65512c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agent.kihustle.tech](https://www.zero.xyz/host/agent.kihustle.tech/llms.txt)