Can agents find your site and its capabilities?
The page registers no tools via the WebMCP browser API (navigator.modelContext).
Fix: Expose your actions to AI agents with the WebMCP browser API: register tools via navigator.modelContext.registerTool. Optionally also publish a /.well-known/webmcp.json tool catalog as a discovery signpost.
Found https://slack.com/llms.txt.
Found at least one "[name](url)" markdown link.
Found a "> summary" blockquote.
First line is a top-level "# Title" heading.
Crawled 9 of 12 discovered pages beyond the homepage.
If your llms.txt file does not follow recommendations, large language models may not be able to understand how you want your website to be crawled or used for training. The [llms.txt](https://llmstxt.org/) file should be a Markdown file containing at least one H1 header.
Lighthouse Agentic Browsing audits ran.
Could not identify a known website platform (custom stack or unrecognised).
Can agents understand your content?
Homepage ignored Accept: text/markdown and returned HTML.
Fix: Serve a markdown version of high-value pages when the client asks for text/markdown. AI summarisers, chatbots and IDE agents prefer markdown — fewer tokens, no DOM noise.
Homepage contains ~2125 elements — heavy.
Fix: Aim for under 1500 elements on the homepage. Heavier DOMs slow first paint and overflow some AI crawlers' parse buffers.
Only 6/88 images have width+height — large CLS risk.
Fix: Set width and height on every <img> so the browser reserves space before the image loads. A layout that shifts while loading makes an AI agent mis-click the element it targeted.
Homepage server response contains 2121 words of visible text — content is reachable without executing JavaScript.
35 headings, no level skips.
Language declared as "en-US".
88 of 88 <img> tags have alt attributes.
262 internal links found.
All four landmark elements present (main, header, footer, nav).
Exactly one <h1> on the homepage.
All 9 reachable key pages have both a <title> and <h1>.
All 9 pages return ≥80 words of visible text without JavaScript.
Can agents actually operate the page?
A well-formed [accessibility tree](http://goo.gle/lighthouse-agentic-a11y) helps AI agents to navigate and interact with the page.
0.264
The page registers no tools via the navigator.modelContext browser API, so an AI agent has no structured way to operate it.
Fix: Expose your site’s actions to AI agents with the WebMCP browser API: call navigator.modelContext.registerTool({ name, description, inputSchema, execute }) from your page so an agent can invoke them. Implement it directly, or with a library like the @mcp-b polyfill (https://mcp-b.ai). Spec: https://github.com/webmachinelearning/webmcp.
883ms (field data from CrUX) — needs improvement.
Fix: Every request an AI agent makes pays this server latency, and agents make many requests per task. Reduce TTFB with edge caching, a CDN, and shipping less server-side work per request.
All 11 agent-critical accessibility audits passed — an agent can perceive and operate the page through its accessibility tree.
`[aria-*]` attributes match their roles passed.
`[aria-hidden="true"]` is not present on the document `<body>` passed.
`[aria-hidden="true"]` elements do not contain focusable descendents passed.
`[role]`s have all required `[aria-*]` attributes passed.
`[role]` values are valid passed.
`[aria-*]` attributes are valid and not misspelled passed.
`[aria-*]` attributes have valid values passed.
Buttons have an accessible name passed.
Document has a `<title>` element passed.
ARIA IDs are unique passed.
Links have a discernible name passed.
Lighthouse accessibility score: 98/100. Agents read the page through its accessibility tree, so this is a proxy for how navigable your site is to an AI agent.
0.010 (field data from CrUX) — good.
Lists the [WebMCP tools](http://goo.gle/webmcp-docs) registered at the time of analysis.
No tool catalog was found at /.well-known/webmcp.json (or /.well-known/webmcp). The catalog is a community convention, not part of the WebMCP standard, so this does not affect WebMCP presence.
Fix: Consider also publishing a tool catalog at /.well-known/webmcp.json: a JSON document with a "spec" of "webmcp/0.1" and a "tools" array, where each tool declares a name and a clear description. It is a community convention (optional, not part of the WebMCP standard) that lets crawlers and agents discover your tools without executing JavaScript.
Can agents safely transact?
/.well-known/oauth-authorization-server returned 404.
Fix: Publish /.well-known/oauth-authorization-server so AI agents discovering your OAuth setup can negotiate flows automatically. Required if your site offers an authenticated API.
/.well-known/oauth-protected-resource returned 404.
Fix: Publish /.well-known/oauth-protected-resource so AI agents discovering your OAuth setup can negotiate flows automatically. Required if your site offers an authenticated API.
No Web Bot Auth signature headers — sites can't verify agent identity.
Fix: Web Bot Auth (IETF HTTP Message Signatures over Signature / Signature-Input) lets you cryptographically verify which agent is hitting you. Several CDNs offer turn-key support; otherwise skip until vendor support matures.
No Content-Security-Policy header on the homepage.
Fix: Add a Content-Security-Policy. Even a strict default-src directive cuts XSS blast radius dramatically. Start in report-only mode to find violations.
No `X-Content-Type-Options: nosniff` header.
Fix: Add `X-Content-Type-Options: nosniff` to prevent browsers (and some agents) from re-interpreting your responses as a different content type.
max-age=31536000, includeSubDomains=true, preload=true.
Homepage scheme is https:.
http://slack.com → https://slack.com/ (1 hop).
No stack-trace markers in the first 5KB.
Homepage HTML references no http:// resources.
Referrer-Policy: no-referrer.
Valid for 43 more days (Sep 3 09:48:09 2026 GMT, issuer: YR2).
Server / X-Powered-By headers don't leak product version.
X-Frame-Options: SAMEORIGIN.