Gaps. Discovery works, but trust does not.

Walmart scores 47 out of 100, landing squarely in the Gaps band, and the shape of the failure is almost comical: the largest retailer in the United States welcomes every AI crawler by name in robots.txt, then slams a PerimeterX challenge in their face the moment they try to fetch the homepage. This is not a site that has thought about agents. It is a site that has thought about bots, decided they are bad, and left the welcome mat out purely as a formality. The most consequential hole is agent posture. Check 4.1 scored zero of six because 13 of 29 fetches returned PerimeterX challenge pages, including walmart.com itself, /cart, /returns, and every single category URL sampled. Check 4.2 compounds this: CAPTCHA is present on homepage, cart, and checkout, and the scanner flagged transaction_blocking as true. An agent cannot transact through a wall. The robots.txt in check 1.1 lists GPTBot, ClaudeBot, PerplexityBot, Google-Extended, and Amazonbot as allowed, but allowance at the policy layer is meaningless when the edge infrastructure challenges them anyway. Six points and four points, gone, because the right hand does not know what the left hand is doing. Structured data is the second disaster. Check 1.2 scored zero of six: across nine sampled URLs spanning category pages, buying guides, and browse listings, not one returned Product or Offer schema. Check 2.1 shows prices exist only in rendered HTML, never in the raw response, meaning any agent that does not run a full headless browser sees nothing but a cart button reading "$0.00." For a catalog this vast, the absence of JSON-LD Product markup is not an oversight, it is a deliberate architectural choice that privileges the React client over machine consumers. Agents that rely on cheap, fast HTML parsing will simply pick Amazon, which serves structured offers at the raw-HTML layer. Checkout transparency is the third weak point. Check 3.2 scored zero of four because the cart page surfaces only "Sign in or create account" with no visible guest path, and check 3.1 could not even resolve the checkout flow because PerimeterX blocked access. Check 3.3 confirmed shipping is calculator-only and tax is invisible pre-auth. For a commerce graph that boasts pickup-today and delivery-today across most sampled URLs, the inability of an agent to see total landed cost before authenticating is a conversion killer in an agent-mediated world. The bright spots are real but narrow. Check 5.1 earned full marks: the 90-day return policy with detailed exception windows and refund timelines is genuinely machine-readable. Check 5.3 and 5.4 also went full, with sale-markup detected on all nine URLs and Bazaarvoice review infrastructure identified. Check 3.5 passed on cart API accessibility, and check 4.3 showed no rate limiting at five requests per second. Walmart clearly has the content assets an agent needs. It just does not expose them through structured contracts. The single biggest opportunity is to reconcile the robots.txt welcome with the PerimeterX wall: either allowlist verified agent user-agents at the edge or publish an agents.json endpoint with authenticated access, because telling crawlers they are invited and then challenging them at the door is the worst of both worlds.