feat: harden prepaid billing and commercial operations

1 files changed, 11 insertions, 0 deletions

diff --git a/internal/usage/observer.go b/internal/usage/observer.go
index cc8b52f..808781f 100644
--- a/internal/usage/observer.go
+++ b/internal/usage/observer.go
@@ -44,6 +44,17 @@ func (o *Observer) Usage() domain.Usage {
 	return o.usage
 }
 
+// Reported distinguishes a real zero-token usage object from a response that
+// omitted usage entirely. Billing must never infer this from token totals.
+func (o *Observer) Reported() bool {
+	if !o.stream {
+		o.parseJSON(o.buffer)
+	} else if len(o.line) > 0 {
+		o.parseSSELine(o.line)
+	}
+	return o.found
+}
+
 func (o *Observer) captureTail(p []byte) {
 	if len(p) >= maxCaptureBytes {
 		o.buffer = append(o.buffer[:0], p[len(p)-maxCaptureBytes:]...)