OpenBMB/ChatDev · error · ValueError

package names cannot be empty

Error message

package names cannot be empty

What it means

Each package spec is stripped of whitespace and must be non-empty; empty strings or whitespace-only entries raise ValueError. This catches degenerate list entries like "" or " " that would otherwise produce a broken uv command line.

Source

Thrown at functions/function_calling/uv_related.py:71

        return path

    def resolve_under_workspace(self, relative_path: str | Path) -> Path:
        candidate = Path(relative_path)
        absolute = candidate if candidate.is_absolute() else self.workspace_root / candidate
        absolute = absolute.expanduser().resolve()
        if self.workspace_root not in absolute.parents and absolute != self.workspace_root:
            raise ValueError("script path is outside workspace root")
        return absolute


def _validate_packages(packages: Sequence[str]) -> List[str]:
    normalized: List[str] = []
    for pkg in packages:
        if not isinstance(pkg, str):
            raise ValueError("package entries must be strings")
        stripped = pkg.strip()
        if not stripped:
            raise ValueError("package names cannot be empty")
        if not _SAFE_PACKAGE_RE.match(stripped):
            raise ValueError(f"unsafe characters detected in package spec {pkg}")
        if stripped.startswith("-"):
            raise ValueError(f"flags are not allowed in packages list: {pkg}")
        normalized.append(stripped)
    if not normalized:
        raise ValueError("at least one package is required")
    return normalized


def _coerce_timeout_seconds(timeout_seconds: Any) -> float | None:
    if timeout_seconds is None:
        return None
    if isinstance(timeout_seconds, bool):
        raise ValueError("timeout_seconds must be a number")
    if isinstance(timeout_seconds, (int, float)):
        value = float(timeout_seconds)
    elif isinstance(timeout_seconds, str):

View on GitHub (pinned to 4fb2db0ea9)

Solutions

  1. Filter empties before calling: [p for p in packages if p and p.strip()]
  2. Fix the splitting logic to drop empty fields (e.g. [x for x in raw.split(",") if x.strip()])
  3. Validate against a schema with minLength on package entries

Example fix

# before
install_python_packages(packages="numpy,,pandas".split(","))
# after
install_python_packages(packages=[p for p in "numpy,,pandas".split(",") if p.strip()])
Defensive patterns

Strategy: validation

Validate before calling

packages = [p.strip() for p in packages if isinstance(p, str) and p.strip()]
if not packages:
    raise ValueError("no packages requested")
install_python_packages(packages=packages, _context=ctx)

Type guard

def no_empty_entries(packages) -> bool:
    return all(isinstance(p, str) and p.strip() for p in packages)

Try / catch

try:
    install_python_packages(packages=packages, _context=ctx)
except ValueError as e:
    if "cannot be empty" in str(e):
        packages = [p for p in packages if p and p.strip()]
        install_python_packages(packages=packages, _context=ctx)
    else:
        raise

Prevention

When it happens

Trigger: Passing packages=["", "numpy"] or packages=[" "]; strings built from empty variables or split of an empty string ("".split() vs "".split(",")); trailing commas producing empty fields ("numpy,".split(",")).

Common situations: Splitting a comma-separated user input with trailing/double commas; config defaults of empty string; form fields left blank but included in the list.

Related errors

AI-assisted analysis of OpenBMB/ChatDev@4fb2db0ea9 (2026-08-27). Data as JSON: /api/errors/581ad2cd786c47e8. Report an issue: GitHub.