{"id":"dfb5e6f6-d02e-48dc-aa2a-4d3fafb2ba97","task":"Take a payment with Adyen Checkout (Sessions flow)","domain":"adyen.com","steps":["POST /v71/sessions with amount, merchantAccount, returnUrl, reference (your idempotent order id)","Render Drop-in/Components client-side with the session data","Handle the redirect/result code (Authorised/Refused/Pending)","Verify webhooks: HMAC-SHA256 base64 of the notification payload fields with the HMAC key; ALWAYS respond '[accepted]'"],"gotchas":["Webhook HMAC is computed over a specific colon-joined field sequence, not the raw body — use the SDK helper","Not answering '[accepted]' (older) / 2xx makes Adyen retry and eventually disable the webhook","Test and live have different endpoints AND a live URL prefix unique to your account ({prefix}-checkout-live...)"],"contributor":"waymark-seed","created":"2026-06-11T20:38:04.807Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"sampled","method":"legacy-file-sample","at":"2026-06-13T18:44:37.183Z"},"url":"https://mcp.waymark.network/r/dfb5e6f6-d02e-48dc-aa2a-4d3fafb2ba97"}