Add minimal application-owned usage events around the existing MandAPI chat call. Generate an internal request ID, use a server-controlled anonymous user ID and record feature, timestamp, duration, status, model response ID and token counts when present. Keep missing usage unknown. Do not log API keys, prompt bodies, customer messages or email addresses. Do not invent MandAPI analytics APIs or claim arbitrary metadata is stored by the gateway. Start with synthetic events and preserve the application's existing error behavior.