# CORE HTML SEO Analyzer

> CORE HTML SEO Analyzer is a paid API for AI agents from api.coregroupimmo.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-17).

Analyzes raw HTML and returns structured SEO metadata including title, meta tags, heading outline, links, JSON-LD blocks, and structural validation checks

## Facts

- Endpoint: POST https://api.coregroupimmo.com/v1/html/analyze?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-17
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/core-html-seo-analyzer-2e86cf0a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_iVe8T28-SJNmmaW4ayVRI

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 core-html-seo-analyzer-2e86cf0a -d '<json body>'
```

Example prompt: Can you audit the SEO structure of this HTML — check the title, meta description, heading outline, any JSON-LD blocks, and flag structural issues like duplicate H1s or wrong heading order?

## When to prefer this

Choose this endpoint when you have raw HTML in hand and need fast, structured SEO metadata extraction and structural validation without any URL fetching or JavaScript execution. It is ideal for pre-publish audits in content pipelines, CI/CD checks, or CMS integrations where HTML is already available. Prefer this over browser-based or URL-fetching SEO tools when you want a lightweight, deterministic parse with no side effects and guaranteed sub-second turnaround on static HTML under 64 KiB.

## Known failure modes

- HTML exceeds 64 KiB limit — request rejected with payload-too-large error
- Empty or missing html field — validation error returned
- Malformed request body — 400 bad request
- Endpoint does not fetch URLs — passing a URL string instead of raw HTML will be parsed as text, not fetched
- JavaScript-rendered content not visible — dynamic SPA content absent from static HTML will not be analyzed

## How this service works

Analyze raw HTML you provide and get structured SEO data as JSON: title, meta description, canonical, H1-H6 outline, links, JSON-LD blocks and structural checks (single H1, heading order, duplicates, JSON-LD validity). Use it to audit a page before publishing. No URL fetching, no JavaScript execution. Max 64 KiB of HTML.

## Output

A JSON object containing: extracted title tag, meta description, canonical URL, a structured H1-H6 heading outline, arrays of internal and external links, all JSON-LD script blocks, and a set of structural SEO check results (e.g. single-H1 pass/fail, heading order validity, duplicate headings, JSON-LD parse validity).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "html": {
   "type": "string",
   "maxLength": 65536,
   "minLength": 1,
   "description": "Raw HTML document or fragment (max 64 KiB)"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "links": [
    {
     "rel": [],
     "href": "/contact",
     "text": "Contact"
    }
   ],
   "title": "Apartment for sale in Aix-en-Provence",
   "checks": {
    "singleH1": true,
    "jsonLdValid": true,
    "headingOrder": true,
    "titlePresent": true,
    "canonicalPresent": true,
    "descriptionPresent": true
   },
   "jsonLd": [],
   "headings": [
    {
     "text": "3-room apartment",
     "level": 1
    },
    {
     "text": "Features",
     "level": 2
    }
   ],
   "canonical": "https://example.com/aix-3-rooms",
   "description": "Bright 3-room apartment",
   "jsonLdErrors": []
  },
  "service": "core-html-seo-analyzer"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/core-html-seo-analyzer-2e86cf0a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.coregroupimmo.com](https://www.zero.xyz/host/api.coregroupimmo.com/llms.txt)