{"rule_id":"AB-030","category":"payments","icon":"💰","title":"Paid Endpoint Response","short_description":"When an agent tries to access a paid feature, your site responds with a clear payment request.","user_value":"This is how agents know a feature costs money and how to pay. Without it, agents hit a wall and move on.","wrong_example":"Paid endpoints return a generic error. Agents don't know payment is required.","right_example":"Paid endpoints clearly communicate the price and payment method.","effort_hint":"complex","estimated_cost":"$100+","severity":"high","pillar":"executability","version":"1.0.0","counted_in_score":true,"check":{"type":"http_probe","sources":["x402"],"target":"/passport/request"},"fix":{"eligible":false,"type":"none","note":"Return HTTP 402 with Payment-Required header on paid endpoints"},"checklist_anchor":"#AB-030","checklist_url":"/agent-readiness-checklist#AB-030","html_url":"/rules/AB-030","json_url":"/rules/AB-030.json","related_rules":[{"rule_id":"AB-031","title":"Payment Challenge Decodable","category":"payments"},{"rule_id":"AB-032","title":"Payment Required Header","category":"payments"},{"rule_id":"AB-033","title":"Payment Recipient","category":"payments"},{"rule_id":"AB-034","title":"Payment Amount","category":"payments"},{"rule_id":"AB-035","title":"Payment Discovery File","category":"payments"},{"rule_id":"AB-038","title":"Payment Facilitator","category":"payments"},{"rule_id":"AB-070","title":"Lightning Payment Support","category":"payments"},{"rule_id":"AB-071","title":"Lightning Payment Details","category":"payments"},{"rule_id":"AB-088","title":"MPP (Machine Payments Protocol) Support","category":"payments"},{"rule_id":"AB-093","title":"SPT (Stripe Payment Terms) Support","category":"payments"}]}