fix: skip malformed document tool call items (#3494)

src/tool_schemas.py

@@ -1258,14 +1258,24 @@ def function_call_to_tool_block(name: str, arguments: str) -> Optional[ToolBlock
         content = "\n".join(parts)
     elif tool_type == "edit_document":
         blocks = []
-        for edit in args.get("edits", []):
+        edits = args.get("edits", [])
+        if not isinstance(edits, list):
+            edits = []
+        for edit in edits:
+            if not isinstance(edit, dict):
+                continue
             blocks.append(
                 f'<<<FIND>>>\n{edit.get("find", "")}\n<<<REPLACE>>>\n{edit.get("replace", "")}\n<<<END>>>'
             )
         content = "\n".join(blocks)
     elif tool_type == "suggest_document":
         blocks = []
-        for s in args.get("suggestions", []):
+        suggestions = args.get("suggestions", [])
+        if not isinstance(suggestions, list):
+            suggestions = []
+        for s in suggestions:
+            if not isinstance(s, dict):
+                continue
             blocks.append(
                 f'<<<FIND>>>\n{s.get("find", "")}\n<<<SUGGEST>>>\n{s.get("replace", "")}\n<<<REASON>>>\n{s.get("reason", "")}\n<<<END>>>'
             )

tests/test_function_call_non_object_args.py

@@ -35,3 +35,27 @@ def test_non_object_arguments_do_not_crash(arguments):
     assert block is not None
     assert block.tool_type == "bash"
     assert block.content == ""
+
+
+def test_edit_document_skips_non_object_edit_items():
+    block = function_call_to_tool_block(
+        "edit_document",
+        '{"edits": ["bad", 42, null, {"find": "old", "replace": "new"}]}',
+    )
+
+    assert block is not None
+    assert block.tool_type == "edit_document"
+    assert block.content == "<<<FIND>>>\nold\n<<<REPLACE>>>\nnew\n<<<END>>>"
+
+
+def test_suggest_document_skips_non_object_suggestion_items():
+    block = function_call_to_tool_block(
+        "suggest_document",
+        '{"suggestions": ["bad", 42, null, {"find": "old", "replace": "new", "reason": "clearer"}]}',
+    )
+
+    assert block is not None
+    assert block.tool_type == "suggest_document"
+    assert block.content == (
+        "<<<FIND>>>\nold\n<<<SUGGEST>>>\nnew\n<<<REASON>>>\nclearer\n<<<END>>>"
+    )