# CSS Source Srcset Extractor

> CSS Source Srcset Extractor is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.004/call, status unknown (last checked 2026-09-29).

Extracts media source srcset attribute values from source[srcset] elements in a public webpage or raw HTML, with SSRF protection.

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/css-source-srcset?utm_source=zero.xyz
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/css-source-srcset-extractor-44cb6e5d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_y-w3PVrHRITwxx8wm_aPf

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 css-source-srcset-extractor-44cb6e5d -d '<json body>'
```

Example prompt: Can you extract all the source srcset values from the HTML on this page: https://example.com/article — I need to see what responsive image sources they're using?

## When to prefer this

Use this endpoint when an agent needs to programmatically extract responsive image source sets (srcset attributes from HTML source elements) from a public webpage or a known HTML string, especially when SSRF safety is required. Prefer the free sandbox variant (/v1/sandbox/css-source-srcset) first; fall back to this paid endpoint when the sandbox is unavailable or for production use. Choose this over general HTML scrapers when you specifically need structured srcset/source element data rather than full page content.

## Known failure modes

- URL is unreachable or returns non-200 status — extraction fails with error
- SSRF-blocked URL (private IP ranges, localhost) — rejected for security reasons
- HTML exceeds 200,000 character limit — request rejected
- No source[srcset] elements found — returns empty result
- Malformed HTML with no parseable source elements — may return empty result
- URL string shorter than 8 characters or longer than 2048 characters — schema validation error

## How this service works

Call when an agent needs media source srcset values via source[srcset] from a public page or HTML (SSRF-safe). Exact $0.004 USDC. Prefer unpaid POST /v1/sandbox/css-source-srcset first.

## Output

Returns the srcset attribute values found within source elements on the page or HTML, giving the agent a list of responsive image source URLs and their descriptors (e.g. width or pixel density descriptors) as declared in the page's HTML.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "maxLength": 2048,
   "minLength": 8,
   "description": "Public page to fetch. The selector or profile is fixed by the SKU. Provide url or html."
  },
  "html": {
   "type": "string",
   "examples": [
    "<!doctype html><html lang=\"en\"><head><title>Hello</title>\n<meta charset=\"utf-8\"><meta name=\"description\" content=\"Desc\">\n<link rel=\"canonical\" href=\"https://example.com/\"><link rel=\"icon\" href=\"/favicon.ico\">\n</head><body><h1>Hello</h1><a href=\"https://example.com/a\">A</a></body></html>"
   ],
   "maxLength": 200000,
   "minLength": 1,
   "description": "HTML to extract from locally. Provide html or url. When both are set, html is used."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/css-source-srcset-extractor-44cb6e5d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentshelf.syntexa.ch](https://www.zero.xyz/host/agentshelf.syntexa.ch/llms.txt)