diff --git a/backend/internal/pkg/apicompat/types.go b/backend/internal/pkg/apicompat/types.go
index 9009463e9d..6031eb41df 100644
--- a/backend/internal/pkg/apicompat/types.go
+++ b/backend/internal/pkg/apicompat/types.go
@@ -59,7 +59,7 @@ type AnthropicContentBlock struct {
 	Text string `json:"text,omitempty"`
 
 	// type=thinking
-	Thinking  string `json:"thinking,omitempty"`
+	Thinking string `json:"thinking,omitempty"`
 	// Signature carries provider encrypted reasoning (e.g. xAI encrypted_content)
 	// so multi-turn Claude clients can round-trip it back on subsequent turns.
 	Signature string `json:"signature,omitempty"`