# tempo.halowerk.com Image TTFB Checker

> tempo.halowerk.com Image TTFB Checker 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 Byte (TTFB) for a specific image resource at a given URL, reporting how long the server takes to begin delivering the image.

## Facts

- Endpoint: POST https://tempo.halowerk.com/v1/pruef/tempo/ttfb/bild
- 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-com-image-ttfb-checker-37f1b516
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_eh0GGBDhZxwkAM8dZXdzO

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-com-image-ttfb-checker-37f1b516 -d '<json body>'
```

Example prompt: Can you check the time to first byte for the hero image at https://example.com/images/hero.jpg and tell me how fast the server starts responding?

## When to prefer this

Use this endpoint when you specifically need to measure the Time to First Byte for an image resource (as opposed to a full page, video, script, or font). It is ideal for diagnosing image-specific server latency, validating CDN performance for image assets, or auditing individual image URLs in a performance pipeline. For page-level TTFB or other resource types (video, font, script), use the corresponding sibling endpoints on tempo.halowerk.com.

## Known failure modes

- Invalid or unreachable image URL returns an error indicating the target could not be fetched
- Private or non-public IP addresses are rejected as invalid targets
- CSS selector matching no image element may fall back to first matching element or return an error
- Timeouts if the remote server is unresponsive
- Malformed URL input fails schema validation

## How this service works

Prüft am Objekt bild den Befund Zeit bis zum ersten Byte.

## Output

Returns a performance finding (Befund) for the specified image resource, indicating the measured Time to First Byte (TTFB) — the elapsed time from initiating an HTTP request to the image URL until the first byte of the response is received. This helps identify server latency, slow origin response, or CDN delivery issues for image assets.

## 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-com-image-ttfb-checker-37f1b516/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)