diff --git a/apps/ai-game-creator-shell/src-tauri/src/agent/direct_tool_calls.rs b/apps/ai-game-creator-shell/src-tauri/src/agent/direct_tool_calls.rs
index 5f3cc5dee..fedf2cc12 100644
--- a/apps/ai-game-creator-shell/src-tauri/src/agent/direct_tool_calls.rs
+++ b/apps/ai-game-creator-shell/src-tauri/src/agent/direct_tool_calls.rs
@@ -444,13 +444,25 @@ fn read_tool_call_lines(path: &Path) -> Vec<DirectToolCall> {
     let Ok(file) = File::open(path) else {
         return Vec::new();
     };
+    let mut reader = BufReader::new(file);
+    let mut buffer = Vec::new();
     let mut calls = Vec::new();
-    for line in BufReader::new(file).lines() {
-        let Ok(line) = line else {
-            break;
-        };
-        if let Some(call) = tool_call_from_line(&line) {
-            calls.push(call);
+    loop {
+        buffer.clear();
+        match reader.read_until(b'\n', &mut buffer) {
+            Ok(0) => break,
+            // 单行解码失败（非法 UTF-8）只跳过这一行，继续读后面的行；
+            // 契约要求「单行损坏跳过该行继续」，不能把后续记录一起丢掉。
+            Ok(_) => match std::str::from_utf8(&buffer) {
+                Ok(line) => {
+                    if let Some(call) = tool_call_from_line(line) {
+                        calls.push(call);
+                    }
+                }
+                Err(_) => continue,
+            },
+            // 读 I/O 错误：无法再定位下一行边界，停止读取（已读到的照常返回）。
+            Err(_) => break,
         }
     }
     calls
@@ -1164,4 +1176,49 @@ mod tests {
         );
     }
 
+    /// 判据：单行损坏（含非法 UTF-8 字节）只跳过损坏行，后续合法记录必须继续读回。
+    #[test]
+    fn tool_call_read_skips_invalid_utf8_line() {
+        let root = init_tool_call_project("tool-call-invalid-utf8");
+        let path = tool_calls_path(root.path());
+        std::fs::create_dir_all(path.parent().expect("parent")).expect("create dir");
+
+        // 形态一（契约原文）：合法行 + 非法字节行 + 合法行 → 读回 2 条。
+        let mut bytes = Vec::new();
+        bytes.extend_from_slice(tool_call_row("item-a", 1000, 1000).as_bytes());
+        bytes.push(b'\n');
+        bytes.extend_from_slice(&[0xff, 0xfe, b'\n']);
+        bytes.extend_from_slice(tool_call_row("item-b", 2000, 2000).as_bytes());
+        bytes.push(b'\n');
+        std::fs::write(&path, &bytes).expect("write invalid utf8 fixture");
+        let calls = read_direct_tool_calls_at(root.path()).expect("read with invalid utf8");
+        assert_eq!(
+            calls.len(),
+            2,
+            "非法 UTF-8 行只跳过该行，后面的合法记录必须读回"
+        );
+        assert_eq!(calls[0].id, "item-a");
+        assert_eq!(calls[1].id, "item-b");
+
+        // 形态二：损坏行缺换行（写入被截断），与紧随其后的记录黏成一行。
+        // 此时被丢掉的只有黏连的那一行，其后的合法记录必须继续读回。
+        let mut bytes = Vec::new();
+        bytes.extend_from_slice(tool_call_row("item-a", 1000, 1000).as_bytes());
+        bytes.push(b'\n');
+        bytes.push(0xff);
+        bytes.extend_from_slice(tool_call_row("item-b", 2000, 2000).as_bytes());
+        bytes.push(b'\n');
+        bytes.extend_from_slice(tool_call_row("item-c", 3000, 3000).as_bytes());
+        bytes.push(b'\n');
+        std::fs::write(&path, &bytes).expect("write truncated utf8 fixture");
+        let calls = read_direct_tool_calls_at(root.path()).expect("read with truncated line");
+        assert_eq!(
+            calls.len(),
+            2,
+            "损坏行缺换行时只丢黏连的那一行，其后的合法记录必须继续读回"
+        );
+        assert_eq!(calls[0].id, "item-a");
+        assert_eq!(calls[1].id, "item-c");
+    }
+
 }