schema.markup
Parse JSON-LD blocks and report JSON syntax errors.
How to use it
schema.markup is exposed by the MCP Web Validator MCP server. Add the server to your MCP client (Claude Desktop, Cursor, Windsurf and others), and the schema.markup tool becomes available to the model automatically. See the full listing for setup details and every tool this server provides.
Install MCP Web Validator
npx -y mcp-web-validatorOther tools in MCP Web Validator (15)
Run a bounded sitemap-first audit of up to eight authorized, same-origin public pages. It respects robots.txt, returns compact page coverage and deduplicated findings, and does not run site-wide link checks.
Fetch one authorized public HTML page and run the combined HTML, SEO/accessibility-signal, and JSON-LD syntax audit. Link checks are optional.
Audit supplied HTML for covered on-page SEO and accessibility signals.
Check up to 20 authorized public links extracted from supplied HTML.
Validate a local CSS file.
Combine the checks for supplied markup; baseurl resolves relative links but does not fetch a page.
Validate a local HTML file.
Validate the markup returned by a public URL.
Check links extracted from supplied HTML.
Combine HTML, optional CSS, SEO, JSON-LD, and bounded link checks in a Markdown report.
Capture desktop, tablet, mobile, or custom viewport screenshots.
Audit titles, descriptions, canonical tags, headings, viewport metadata, image alt attributes, and Open Graph metadata.
Parse supplied CSS for syntax errors inside the Worker.
Validate raw HTML markup already supplied in the conversation.
Check JSON-LD blocks in supplied HTML for JSON syntax errors.