# Sharelint

> The link linter: score and fix how a URL previews in 12 apps, what AI assistants can read, and whether it opens your app.

Free link checker: see how a URL previews on WhatsApp, Facebook, X, LinkedIn and 8 more apps, whether ChatGPT, Claude and Perplexity can read it, and whether it opens your iOS or Android app.

Sharelint is built and run by DevLab Technologies LLC.

The checker fetches a public URL with each platform’s real crawler User-Agent, parses the raw HTML head (no JavaScript, like the crawlers), downloads the preview images to read their size and dimensions, and reports per-platform layouts and problems.

It also scores AI visibility: whether AI crawlers and assistants (OAI-SearchBot, ChatGPT-User, Claude-SearchBot, Claude-User, PerplexityBot, Perplexity-User and others) are allowed by robots.txt and reach the page, and what text they read from the raw HTML.

It checks app links too: whether a shared URL opens the site’s iOS app (apple-app-site-association, including Apple’s CDN copy) or Android app (assetlinks.json, including Google’s Digital Asset Links verification).

Every report ends with an ordered list of fixes, each with steps and copy-ready code filled from the page.

## MCP server

- Remote MCP endpoint (Streamable HTTP, no auth): https://sharelint.com/api/mcp. Tools: check_link_preview (share previews in 12 apps), check_ai_visibility (ChatGPT, Claude, Perplexity and other AI bots), check_app_links (iOS Universal Links and Android App Links) and check_url (all three). Each returns a Markdown report that starts with ordered, copy-ready fixes.

## API

- [Markdown report](https://sharelint.com/api/preview?format=md&url=https://example.com): `GET /api/preview?url=<url>&format=md`. Returns a Markdown report with share preview, AI visibility and app links scores, ordered fixes with copy-ready code, a per-platform table and the meta tags found. Best for LLM agents and pull-request comments. Add `&section=share`, `ai` or `apps` for one view.
- [JSON report](https://sharelint.com/api/preview?url=https://example.com): `GET /api/preview?url=<url>`. Returns { result, pageIssues, platforms[], score, ai, apps, fixes }. `ai` holds the AI visibility score, per-bot access and the extracted page text; `apps` holds iOS and Android app link status (score is null when the site has no app); `fixes` has ordered fixes for each view.
- [OpenAPI spec](https://sharelint.com/openapi.json): full schema. Optional `crawler` parameter: facebook, whatsapp, twitter, telegram, linkedin, discord, slack, imessage, browser.

## Guides

- [AI visibility checker for ChatGPT, Claude and Perplexity](https://sharelint.com/ai-visibility-checker.md): Check whether AI search tools and assistants can reach your page, which bots your robots.txt blocks, and what text they actually read when they do.
- [App links checker for iOS Universal Links and Android App Links](https://sharelint.com/app-links-checker.md): Check whether a shared link opens your iOS or Android app instead of the browser: apple-app-site-association, assetlinks.json, and the copies Apple and Google have cached.
- [Facebook link preview checker](https://sharelint.com/facebook-link-preview.md): Facebook builds link cards from Open Graph tags fetched by facebookexternalhit. The same cache is shared by Messenger and Instagram DMs.
- [WhatsApp link preview checker](https://sharelint.com/whatsapp-link-preview.md): WhatsApp generates previews on the sender’s device from the og: tags, and is strict about image weight and format.
- [X (Twitter) card validator alternative](https://sharelint.com/twitter-card-validator.md): X reads twitter: tags first and falls back to Open Graph. X retired its official Card Validator preview, so you need another way to check cards.
- [Telegram link preview checker](https://sharelint.com/telegram-link-preview.md): Telegram shows og:site_name as a coloured header, then the title, description and image.
- [LinkedIn link preview checker](https://sharelint.com/linkedin-link-preview.md): LinkedIn shows the og:title, image and domain. Descriptions are no longer shown in the feed.
- [iMessage link preview checker](https://sharelint.com/imessage-link-preview.md): iMessage fetches the page from the sender’s device and shows only the title, domain and image or icon.
- [Discord embed preview checker](https://sharelint.com/discord-embed-preview.md): Discord renders an embed coloured by theme-color, with the site name, title, description and image.
- [Slack unfurl preview checker](https://sharelint.com/slack-unfurl-preview.md): Slackbot unfurls links using the favicon, og:site_name, title, description and image.
- [Messenger link preview checker](https://sharelint.com/messenger-link-preview.md): Messenger uses the Facebook crawler and cache, shown as a rounded chat card.
- [Instagram link preview checker](https://sharelint.com/instagram-link-preview.md): Instagram only shows link cards in direct messages. Links in captions are not clickable.
- [Snapchat link preview checker](https://sharelint.com/snapchat-link-preview.md): Snapchat shows a compact card with a thumbnail, title and domain in chats and Snap attachments.
- [TikTok link preview checker](https://sharelint.com/tiktok-link-preview.md): TikTok shows minimal link previews, and only in DMs. Links in captions are plain text.

## Optional

- [Full guide text](https://sharelint.com/llms-full.txt): every platform guide plus the FAQ in one file