diff --git a/src/providers/openai.rs b/src/providers/openai.rs
index c50a28f..073bd35 100644
--- a/src/providers/openai.rs
+++ b/src/providers/openai.rs
@@ -160,7 +160,7 @@ impl LLMProvider for OpenAIProvider {
                         for (j, item) in content.iter().enumerate() {
                             if item.get("type").and_then(|t| t.as_str()) == Some("image_url") {
                                 if let Some(url_str) = item.get("image_url").and_then(|u| u.get("url")).and_then(|v| v.as_str()) {
-                                    let prefix = &url_str[..20.min(url_str.len())];
+                                    let prefix: String = url_str.chars().take(20).collect();
                                     tracing::debug!(msg_idx = i, item_idx = j, image_prefix = %prefix, image_url_len = %url_str.len(), "Image in LLM request (first 20 bytes shown)");
                                 }
                             }
@@ -188,8 +188,8 @@ impl LLMProvider for OpenAIProvider {
         // Debug: Log LLM response (only in debug builds)
         #[cfg(debug_assertions)]
         {
-            let resp_preview = &text[..text.len().min(100)];
-            tracing::debug!(status = %status, response_preview = %resp_preview, response_len = %text.len(), "LLM response (first 100 bytes shown)");
+            let resp_preview: String = text.chars().take(100).collect();
+            tracing::debug!(status = %status, response_preview = %resp_preview, response_len = %text.len(), "LLM response (first 100 chars shown)");
         }
 
         if !status.is_success() {