# tempo.halowerk.com – TTFB Check for Font Resources

> tempo.halowerk.com – TTFB Check for Font Resources 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 Time to First Byte (TTFB) for a font/typeface resource at a given URL, returning latency timing data.

## Facts

- Endpoint: POST https://tempo.halowerk.com/v1/pruef/tempo/ttfb/schrift
- 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-ttfb-check-for-font-resources-de80482f
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_S6VfPbhM5fXvsJCeqoxCX

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-ttfb-check-for-font-resources-de80482f -d '<json body>'
```

Example prompt: Can you check the time to first byte for the font file at https://fonts.example.com/myfont.woff2 and tell me how fast the server is responding?

## When to prefer this

Use this endpoint specifically when you need to isolate and measure the TTFB of a font or typeface resource (woff, woff2, ttf, otf, etc.) hosted at a public URL. Prefer this over general page-speed tools when your goal is granular font asset latency analysis rather than full-page performance. Choose this over sibling endpoints (e.g. image or video TTFB) when the target resource is a font file.

## Known failure modes

- URL is unreachable or returns a non-2xx status — measurement fails or returns error
- URL points to a private/non-public resource — connection refused or timeout
- Invalid CSS selector provided — selector mismatch or no matching element
- Malformed or too-long URL — validation error
- Font server is rate-limiting — intermittent failures or elevated TTFB readings

## How this service works

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

## Output

Returns a TTFB (Time to First Byte) timing measurement for the specified font resource URL, indicating how long the server takes to respond with the first byte of data. May include connection diagnostic details.

## 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-ttfb-check-for-font-resources-de80482f/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)