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.
Per llmstxt.org, follow the H1 with a "> short summary" blockquote.
Fix: Add a "> One-sentence description of your site." blockquote under the H1.
Found a Markdown guide at /AGENTS.md.
Found https://tatcha.com/llms.txt.
Found at least one "[name](url)" markdown link.
First line is a top-level "# Title" heading.
Crawled 4 of 12 discovered pages beyond the homepage.
Lighthouse Agentic Browsing audits ran.
Built on Shopify.
Can agents understand your content?
Homepage contains ~2254 elements — heavy.
Fix: Aim for under 1500 elements on the homepage. Heavier DOMs slow first paint and overflow some AI crawlers' parse buffers.
103 of 107 images have alt attributes (96%).
Fix: Add alt text to the remaining images. Empty alt="" is fine for purely-decorative graphics.
Homepage returns text/markdown when requested.
Homepage server response contains 3464 words of visible text — content is reachable without executing JavaScript.
9 headings, no level skips.
Language declared as "en".
107/107 images set width and height — no layout shift.
150 internal links found.
All four landmark elements present (main, header, footer, nav).
Exactly one <h1> on the homepage.
All 4 reachable key pages have both a <title> and <h1>.
All 4 pages return ≥80 words of visible text without JavaScript.
Can agents actually operate the page?
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.
Lighthouse accessibility score: 88/100. Agents read the page through its accessibility tree, so this is a proxy for how navigable your site is to an AI agent.
Fix: Resolve the failing accessibility audits below — each one removes an element or relationship an agent would otherwise be blind to.
0/1 data-collecting forms expose errors via ARIA attributes.
Fix: Wire inputs to their error containers with `aria-describedby` and toggle `aria-invalid` on validation failure. Agents that can't see styled error text rely on these attributes.
No HTML5 validation hints (pattern / minlength / maxlength / min / max) on any data-collecting form input.
Fix: Publish input constraints via HTML attributes so agents and browsers can validate client-side.
All 13 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.
Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children. passed.
`[role]`s are contained by their required parent element 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.
`<frame>` or `<iframe>` elements have a title passed.
Links have a discernible name passed.
All 1 data-collecting forms set autocomplete on at least one field.
6 of 6 visible interactive form fields have labels.
1/1 data-collecting forms mark required fields.
0.010 (field data from CrUX) — good.
639ms (field data from CrUX) — good.
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?
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.
HSTS max-age=7889238 is below six months.
Fix: Raise max-age to at least 15768000 (six months). The HSTS preload list requires 31536000 (one year).
No Referrer-Policy header on the homepage.
Fix: Add `Referrer-Policy: strict-origin-when-cross-origin` so outbound links don't leak full URLs (including query strings) to third parties.
/.well-known/oauth-authorization-server returns parseable JSON.
/.well-known/oauth-protected-resource returns parseable JSON.
cf-ray: a1eb77285ad8a5c5-AMS (Cloudflare); Server: cloudflare
CSP header present.
Homepage scheme is https:.
http://tatcha.com → https://tatcha.com/ (1 hop).
No stack-trace markers in the first 5KB.
Homepage HTML references no http:// resources.
Valid for 30 more days (Aug 20 20:30:32 2026 GMT, issuer: E7).
Server / X-Powered-By headers don't leak product version.
X-Content-Type-Options: nosniff.
X-Frame-Options: DENY.
Can agents shop and check out?
Found the human-approval-for-checkout rule.
Content-Type: text/markdown; charset=utf-8.
Mentions the store ("tatcha") — looks customised beyond the default.
References UCP / a UCP version or /.well-known/ucp.
No secret/token or admin-path references found.
Found at https://tatcha.com/agents.md.
References the UCP MCP endpoint (/api/ucp/mcp).
Manifest parses as JSON.
Manifest reachable at https://tatcha.com/.well-known/ucp.
Services: dev.ucp.shopping.
Transports: mcp, embedded.