FoundationAgents/OpenManus · error · RuntimeError

Failed to write file: {e}

Error message

Failed to write file: {e}

What it means

Catch-all RuntimeError from DockerSandbox.write_file (app/sandbox/core/sandbox.py:230): failures while creating the parent dir (run_command mkdir), building the tar stream (_create_tar_stream), or pushing it with container.put_archive. The underlying cause is in {e}. Note put_archive writes to parent_dir or "/" with only the basename in the tar, so path resolution mistakes surface here too.

Source

Thrown at app/sandbox/core/sandbox.py:230

            resolved_path = self._safe_resolve_path(path)
            parent_dir = os.path.dirname(resolved_path)

            # Create parent directory
            if parent_dir:
                await self.run_command(f"mkdir -p {parent_dir}")

            # Prepare file data
            tar_stream = await self._create_tar_stream(
                os.path.basename(path), content.encode("utf-8")
            )

            # Write file
            await asyncio.to_thread(
                self.container.put_archive, parent_dir or "/", tar_stream
            )

        except Exception as e:
            raise RuntimeError(f"Failed to write file: {e}")

    def _safe_resolve_path(self, path: str) -> str:
        """Safely resolves container path, preventing path traversal.

        Args:
            path: Original path.

        Returns:
            Resolved absolute path.

        Raises:
            ValueError: If path contains potentially unsafe patterns.
        """
        # Check for path traversal attempts
        if ".." in path.split("/"):
            raise ValueError("Path contains potentially unsafe patterns")

        resolved = (

View on GitHub (pinned to 52a13f2a57)

Solutions

1. Read {e} — it distinguishes mkdir failure vs put_archive failure.
2. Write inside config.work_dir (the rw-mounted volume) rather than container-system paths.
3. Check the volume bindings are mode 'rw' and the host dir is writable.
4. Clean container disk (docker system prune inside the image's storage) or increase storage.

writable = (await sandbox.run_command(f"test -w {shlex.quote(os.path.dirname(abs_path))} && echo 1")).strip() == "1"

try:
    await sandbox.write_file(path, content)
except RuntimeError as e:
    log.error("write failed: %r", e)
    raise

When it happens

Trigger: mkdir -p failing because the parent is read-only or owned by another user in the container; put_archive failing due to permissions on the target dir; tar creation errors (invalid name for very long basenames); Docker API errors (daemon restarting, disk full).

Common situations: Writing to system paths (/etc) as a non-root container user; container disk full after heavy use; basename/path mismatch when the caller passes a path ending in '/' (empty basename); volume mount is read-only (mode 'ro' in bindings).

Related errors

• Failed to read file: {e}
• Failed to create sandbox: {e}
• File not found: {path}
• Source file is empty: {src_path}
• Failed to copy file: {e}

AI-assisted analysis of FoundationAgents/OpenManus@52a13f2a57 (2026-08-15). Data as JSON: /api/errors/491532d1f3e37a02. Report an issue: GitHub.