# Tempo Halowerk – Script TTFB Check

> Tempo Halowerk – Script TTFB Check is a paid API for AI agents from tempo.halowerk.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-16).

Measures the Time to First Byte (TTFB) for a script resource at a given public URL, optionally targeted by CSS selector.

## Facts

- Endpoint: POST https://tempo.halowerk.com/v1/pruef/tempo/ttfb/skript
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-16
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/tempo-halowerk-script-ttfb-check-cfa1a097
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Dkeg45EoB7tizuRzvh_pl

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-script-ttfb-check-cfa1a097 -d '<json body>'
```

Example prompt: Can you check the Time to First Byte for the script at https://cdn.example.com/app.js and tell me how fast the server is responding?

## When to prefer this

Use this endpoint when you specifically need to measure Time to First Byte for a script (JavaScript) resource, as opposed to images, fonts, videos, or full page loads. It is the right choice when diagnosing slow JS delivery from CDNs, third-party script hosts, or origin servers, and when you want granular TTFB data isolated to a single script asset rather than overall page load metrics.

## Known failure modes

- URL is not publicly reachable — endpoint cannot connect to the target
- URL does not resolve to a script resource — wrong resource type targeted
- CSS selector matches zero elements — no script found at given selector
- Target host blocks automated probes — connection refused or timeout
- Invalid URL format provided — schema validation error
- Network congestion causes inconsistent TTFB readings

## How this service works

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

## Output

Returns the measured Time to First Byte (TTFB) for the targeted script resource, indicating how quickly the server begins delivering data after receiving a request. The finding includes timing data that can be used to diagnose server, network, or CDN latency issues specific to script 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-script-ttfb-check-cfa1a097/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)