FoundationAgents/OpenManus · error · ToolError

Invalid `view_range`. It should be a list of two integers.

Error message

Invalid `view_range`. It should be a list of two integers.

What it means

Error "Invalid `view_range`. It should be a list of two integers." thrown in FoundationAgents/OpenManus.

Source

Thrown at app/tool/str_replace_editor.py:248

            )

        return CLIResult(output=stdout, error=stderr)

    async def _view_file(
        self,
        path: PathLike,
        operator: FileOperator,
        view_range: Optional[List[int]] = None,
    ) -> CLIResult:
        """Display file content, optionally within a specified line range."""
        # Read file content
        file_content = await operator.read_file(path)
        init_line = 1

        # Apply view range if specified
        if view_range:
            if len(view_range) != 2 or not all(isinstance(i, int) for i in view_range):
                raise ToolError(
                    "Invalid `view_range`. It should be a list of two integers."
                )

            file_lines = file_content.split("\n")
            n_lines_file = len(file_lines)
            init_line, final_line = view_range

            # Validate view range
            if init_line < 1 or init_line > n_lines_file:
                raise ToolError(
                    f"Invalid `view_range`: {view_range}. Its first element `{init_line}` should be "
                    f"within the range of lines of the file: {[1, n_lines_file]}"
                )
            if final_line > n_lines_file:
                raise ToolError(
                    f"Invalid `view_range`: {view_range}. Its second element `{final_line}` should be "
                    f"smaller than the number of lines in the file: `{n_lines_file}`"
                )

View on GitHub (pinned to 52a13f2a57)

Solutions

1. Pass `view_range` as a list of two integers, e.g. [1, 50]; use -1 as the second element for end of file.

When it happens

Trigger: Raised when `view_range` is not a list of exactly two integers.

Common situations: See trigger scenarios.

AI-assisted analysis of FoundationAgents/OpenManus@52a13f2a57 (2026-08-15). Data as JSON: /api/errors/989e3f78507fe95f. Report an issue: GitHub.