diff --git a/src/agent/agent_loop.rs b/src/agent/agent_loop.rs
index 1ef5bf5..8f2069a 100644
--- a/src/agent/agent_loop.rs
+++ b/src/agent/agent_loop.rs
@@ -933,6 +933,21 @@ impl AgentLoop {
                 Some(tool_defs)
             };
 
+            // Defense-in-depth: sanitize incomplete tool call sequences
+            // before EVERY LLM request, not just once at process() entry.
+            // This catches edge cases where compression, persistence races,
+            // or delta message merging may have introduced orphaned sequences
+            // that survived the initial sanitization.
+            let mid_loop_removed =
+                crate::bus::message::sanitize_incomplete_tool_call_sequences(&mut messages);
+            if mid_loop_removed > 0 {
+                tracing::warn!(
+                    iteration = iteration,
+                    removed_count = mid_loop_removed,
+                    "Mid-loop sanitize removed incomplete tool call sequences before LLM request"
+                );
+            }
+
             // 过滤超出轮次和数量限制的图片
             let filtered_messages = filter_images_by_age_and_count(
                 &messages,