# CORE HTML SEO Analyzer

> CORE HTML SEO Analyzer is a paid API for AI agents from 92-222-181-125.sslip.io, 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 description, canonical URL, heading outline, links, JSON-LD blocks, and structural validation checks.

## Facts

- Endpoint: POST https://92-222-181-125.sslip.io/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-70cd8dfa
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_302FE46Vaj6U48_uFlrYF

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-70cd8dfa -d '<json body>'
```

Example prompt: Can you run an SEO audit on this HTML and tell me if the title, meta description, canonical, heading structure, and JSON-LD are all correct — flag any issues like missing H1, wrong heading order, or invalid structured data?

## When to prefer this

Use this endpoint when you have raw HTML content and need a fast, structured SEO audit without fetching any URLs or executing JavaScript. Ideal for pre-publish checks in a CMS pipeline, static site generator, or content workflow where you already have the HTML string and need immediate JSON-formatted SEO diagnostics including heading validation and JSON-LD verification.

## Known failure modes

- HTML exceeding 64 KiB returns a size validation error
- Empty or missing html field returns a 400 bad request
- Malformed or non-UTF-8 HTML may produce incomplete extractions
- JSON-LD blocks with syntax errors are flagged as invalid rather than parsed
- Fragments missing head section will show null for title, meta description, and canonical

## 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 page title, meta description, canonical URL, a nested H1–H6 heading outline, arrays of internal and external links, parsed JSON-LD script blocks, and a set of structural checks indicating whether a single H1 exists, headings are in correct order, no duplicates are present, and JSON-LD blocks are valid.

## Request schema (JSON Schema)

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

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/core-html-seo-analyzer-70cd8dfa/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from 92-222-181-125.sslip.io](https://www.zero.xyz/host/92-222-181-125.sslip.io/llms.txt)