# Tempo Halowerk – iframe Render Start Time Check

> Tempo Halowerk – iframe Render Start Time Check is a paid API for AI agents from tempo.halowerk.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Measures the time-to-first-render (render start) of an iframe object on a given web page, returning a performance audit result.

## Facts

- Endpoint: POST https://tempo.halowerk.com/v1/pruef/tempo/renderstart/iframe
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/tempo-halowerk-iframe-render-start-time-check-bedaf0e6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_8ROtya971eMecJVa-EqaW

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 tempo-halowerk-iframe-render-start-time-check-bedaf0e6 -d '<json body>'
```

Example prompt: Check how long it takes for the iframe on https://example.com/embed-page to start rendering visibly — I want the render start time performance metric for that iframe.

## When to prefer this

Use this endpoint when you specifically need to measure the time-to-render-start metric for an iframe element on a public web page. It is distinct from full-page render timing, first contentful paint, or time-to-first-byte checks. Choose this when diagnosing or benchmarking embedded content (third-party widgets, payment forms, video embeds) and you need iframe-scoped render start latency rather than general page performance.

## Known failure modes

- Target URL is not publicly accessible — returns an error or timeout
- No iframe found on the target page — audit returns no result or an object-not-found error
- CSS selector matches zero or multiple elements — first match is used or error returned
- Invalid or malformed URL input — validation error
- Page requires authentication or blocks headless browsers — measurement fails or returns incomplete data

## How this service works

Prüft am Objekt iframe den Befund Zeit bis zum sichtbaren Renderstart.

## Output

Returns a performance measurement indicating the time elapsed until the iframe element begins its visible render (render start), expressed as a duration metric. This may include timing data scoped to the specific iframe object on the target page.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "ziel": {
   "oneOf": [
    {
     "type": "string",
     "maxLength": 2048,
     "minLength": 1,
     "description": "Öffentliche HTTP(S)-Adresse; bei DNS-Befunden Domain oder öffentliche IP."
    },
    {
     "type": "object",
     "required": [
      "adresse"
     ],
     "properties": {
      "adresse": {
       "type": "string",
       "maxLength": 2048,
       "minLength": 1
      },
      "selektor": {
       "type": "string",
       "maxLength": 240,
       "minLength": 1,
       "description": "CSS-Selektor: genau ein Objekt, sonst erster Treffer des Objektfilters."
      },
      "vergleich": {
       "type": "string",
       "maxLength": 2048,
       "description": "Öffentliche Vergleichsadresse für Link-, Sitemap- oder Sprachbefunde."
      },
      "user_agent": {
       "type": "string",
       "pattern": "^[A-Za-z0-9_-]{1,80}$"
      },
      "dkim_selektor": {
       "type": "string",
       "pattern": "^[A-Za-z0-9_-]{1,63}$"
      }
     },
     "additionalProperties": false
    }
   ]
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/tempo-halowerk-iframe-render-start-time-check-bedaf0e6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from tempo.halowerk.com](https://www.zero.xyz/host/tempo.halowerk.com/llms.txt)