diff --git a/internal/p9/beads.go b/internal/p9/beads.go
index 2809a58..e5ea367 100644
--- a/internal/p9/beads.go
+++ b/internal/p9/beads.go
@@ -920,8 +920,7 @@ func containsBdRef(s string) bool {
 	lower := strings.ToLower(s)
 	idx := strings.Index(lower, "bd-")
 	for idx != -1 {
-		rest := lower[idx+3:]
-		if len(rest) > 0 && isAlphanumeric(rest[0]) {
+		if idx+3 < len(lower) && isAlphanumeric(lower[idx+3]) {
 			return true
 		}
 		next := strings.Index(lower[idx+1:], "bd-")
diff --git a/internal/p9/server.go b/internal/p9/server.go
index ca4c99e..2d343e2 100644
--- a/internal/p9/server.go
+++ b/internal/p9/server.go
@@ -600,7 +600,7 @@ func (s *Server) open(cs *connState, fc *plan9.Fcall) *plan9.Fcall {
 	return &plan9.Fcall{Type: plan9.Ropen, Tag: fc.Tag, Qid: qid}
 }
 
-func (s *Server) create(cs *connState, fc *plan9.Fcall) *plan9.Fcall {
+func (s *Server) create(_ *connState, fc *plan9.Fcall) *plan9.Fcall {
 	return errFcall(fc, "create not supported")
 }