New tool: restart_language_server

README.md

@@ -596,6 +596,7 @@ Here is the full list of Serena's tools with a short description (output of `uv
 * `read_memory`: Reads the memory with the given name from Serena's project-specific memory store.
 * `replace_lines`: Replaces a range of lines within a file with new content.
 * `replace_symbol_body`: Replaces the full definition of a symbol.
+* `restart_language_server`: Restarts the language server, may be necessary when edits not through Serena happen.
 * `search_in_all_code`: Performs a search for a pattern in all code files (and only in code files) in the project.
 * `summarize_changes`: Provides instructions for summarizing the changes made to the codebase.
 * `think_about_collected_information`: Thinking tool for pondering the completeness of collected information.

src/serena/agent.py

@@ -502,6 +502,20 @@ class ToolMarkerDoesNotRequireActiveProject:
     pass
 
 
+class RestartLanguageServerTool(Tool):
+    """Restarts the language server, may be necessary when edits not through Serena happen."""
+
+    def apply(self) -> str:
+        """Use this tool only on explicit user request or after confirmation.
+        It may be necessary to restart the language server if the user performs edits
+        not through Serena, so the language server state becomes outdated and further editing attempts lead to errors.
+
+        If such editing errors happen, you should suggest using this tool.
+        """
+        self.agent.reset_language_server()
+        return "OK"
+
+
 class ReadFileTool(Tool):
     """
     Reads a file within the project directory.