_handle_str_replace() — langchain Function Reference

Source Code

libs/partners/anthropic/langchain_anthropic/middleware/anthropic_tools.py lines 928–963

    def _handle_str_replace(self, args: dict, tool_call_id: str | None) -> Command:
        """Handle `str_replace` command."""
        path = args["path"]
        old_str = args["old_str"]
        new_str = args.get("new_str", "")

        full_path = self._validate_and_resolve_path(path)

        if not full_path.exists():
            msg = f"File not found: {path}"
            raise FileNotFoundError(msg)

        # Read file
        content = full_path.read_text()

        # Replace string
        if old_str not in content:
            msg = f"String not found in file: {old_str}"
            raise ValueError(msg)

        new_content = content.replace(old_str, new_str, 1)

        # Write back
        full_path.write_text(new_content)

        return Command(
            update={
                "messages": [
                    ToolMessage(
                        content=f"String replaced in {path}",
                        tool_call_id=tool_call_id,
                        name=self.tool_name,
                    )
                ]
            }
        )