Web Validator by DigestSEO

Validate HTML and CSS, audit technical SEO and JSON-LD, and check user-authorized public links.

CommunityOnlineNo sign-inGlobalFreeRead-only

What it can do

  • Validate Html: Sends supplied HTML markup to the W3C Nu HTML Checker and returns validation messages. Use only markup you are authorized to share.
  • Validate Css: Parses supplied CSS locally and returns syntax messages without contacting an external service.
  • Audit Seo Metadata: Analyzes supplied HTML locally for title, description, canonical, viewport, heading, image-alt, and Open Graph issues.

What data it sees

Do you need an account

No: the server works without sign-in

Validate HTML and CSS, audit technical SEO and JSON-LD, and check user-authorized public links. By digestseo.com.

How to connect

How to connect Web Validator by DigestSEO to Claude

The server address to paste into Claude settings:

https://web-validator--digestseo.run.tools

  1. Open Claude (claude.ai or the desktop app).
  2. Go to Settings → Connectors.
  3. Click Add custom connector.
  4. Paste the server address copied below into Remote MCP server URL and click Add.
  5. In a chat, click + → Connectors and switch the new connector on.

Custom connectors are available on Free, Pro, Max, Team and Enterprise plans (Free is limited to one). On Team and Enterprise an organization Owner adds the connector first under Organization settings → Connectors.

Authorization

After you click Add, a sign-in window for the service opens. Sign in with your own account and approve access. Claude never sees your password.

How to connect Web Validator by DigestSEO to ChatGPT

The server address to paste into ChatGPT settings:

https://web-validator--digestseo.run.tools

  1. Open ChatGPT in a browser (chatgpt.com). A Plus, Pro, Business, Enterprise or Edu plan is required.
  2. Turn on developer mode once: Settings → Apps → Advanced settings → Developer mode.
  3. Open Settings → Connectors and click Create.
  4. Fill in the form: Name (anything), Description (one line about what the service does), MCP server URL (copy it below).
  5. Under Authentication choose OAuth if the service requires sign-in, otherwise None. Click Create.
  6. In a new chat open + → Apps/Connectors and enable the connector.

OpenAI has renamed this section before (Connectors → Apps/Plugins). If the label differs, search settings for "developer mode". On Business/Enterprise workspaces an admin must allow custom connectors first.

Authorization

On first use ChatGPT opens the service's sign-in window. Sign in and approve access.

How to connect Web Validator by DigestSEO to Cursor

The server address to paste into Cursor settings:

https://web-validator--digestseo.run.tools

Fastest: click Open in Cursor below and confirm the prompt.

Manually:

  1. In Cursor open Settings → Cursor Settings → MCP and click Add new global MCP server.
  2. Paste the JSON copied below into ~/.cursor/mcp.json (per project: .cursor/mcp.json in the repo root).
  3. Save the file. The server appears in the MCP list; authorize it there if asked.

Authorization

If the service needs sign-in, an authorize button appears next to the server in the MCP list.

Server tool list (6)

Raw names from tools/list. Only developers need these.

validate_htmlSends supplied HTML markup to the W3C Nu HTML Checker and returns validation messages. Use only markup you are authorized to share.
validate_cssParses supplied CSS locally and returns syntax messages without contacting an external service.
audit_seo_metadataAnalyzes supplied HTML locally for title, description, canonical, viewport, heading, image-alt, and Open Graph issues.
validate_schema_markupParses JSON-LD blocks in supplied HTML and reports JSON syntax problems without contacting external services.
check_broken_linksChecks up to 25 public HTTP(S) links found in supplied HTML. It does not follow redirects or fetch response bodies. Use only URLs you are authorized to inspect.
generate_validation_reportCombines W3C Nu HTML validation with local CSS, SEO, and JSON-LD checks for supplied markup. Optionally checks public links when the user has authorized those requests.