abhigyanpatwari/GitNexus · error · SandboxError

sandbox_dependencies must be a list

Error message

sandbox_dependencies must be a list

What it means

Raised by _sandbox_dependency_declarations when the task's `sandbox_dependencies` field exists but is not a list. This is the top-level type gate for dependency declarations, evaluated before any per-entry validation. An absent field defaults to `[]` (accepted); a present-but-wrong-type field (string, dict, number) is rejected.

Source

Thrown at eval/workflow_bench/task_assets.py:566

    for raw in declarations:
        relative = PurePosixPath(raw)
        if relative.is_absolute() or not relative.parts or ".." in relative.parts:
            raise SandboxError(f"sandbox_copy must be a repository-relative path: {raw!r}")
        _validate_manifest_path(relative)
        paths.append(relative)
    for index, path in enumerate(paths):
        for other in paths[index + 1 :]:
            if path == other or path in other.parents or other in path.parents:
                raise SandboxError(f"sandbox_copy declarations overlap: {path} and {other}")
    return declarations, tuple(paths)


def _sandbox_dependency_declarations(
    task: Mapping[str, Any],
) -> tuple[_DependencyDeclaration, ...]:
    raw_declarations = task.get("sandbox_dependencies", [])
    if not isinstance(raw_declarations, list):
        raise SandboxError("sandbox_dependencies must be a list")
    declarations: list[_DependencyDeclaration] = []
    for item in raw_declarations:
        if (
            not isinstance(item, Mapping)
            or set(item) != {"source", "target"}
            or not all(isinstance(item[field], str) and item[field] for field in ("source", "target"))
        ):
            raise SandboxError("sandbox_dependencies entries require only nonblank source and target")
        source = str(item["source"])
        target = str(item["target"])
        source_path = PurePosixPath(source)
        target_path = PurePosixPath(target)
        if source_path.is_absolute() or ".." in source_path.parts or not source_path.parts:
            raise SandboxError(f"dependency source must stay inside the repository: {source_path}")
        if target_path.is_absolute() or ".." in target_path.parts or not target_path.parts:
            raise SandboxError(f"dependency target must stay inside the clone: {target_path}")
        _validate_manifest_path(source_path)
        _validate_manifest_path(target_path)

View on GitHub (pinned to d540b00184)

Solutions

1. Wrap dependency declarations in a list, even for a single entry: `[{"source": "...", "target": "..."}]`.
2. Omit the field entirely if there are no dependencies — both absent and `[]` are valid.
3. Validate the task schema before prepare() (see validationCode).
4. If templating, ensure the template always emits an array even for one element.

Example fix

// before
{"sandbox_dependencies": {"source": "node_modules", "target": "node_modules"}}

// after
{"sandbox_dependencies": [{"source": "node_modules", "target": "node_modules"}]}

def validate_sandbox_dependencies_list(task: dict) -> None:
    raw = task.get("sandbox_dependencies", [])
    if not isinstance(raw, list):
        raise ValueError("sandbox_dependencies must be a list")

validate_sandbox_dependencies_list(task)

from typing import Any

def is_sandbox_dependencies_list(value: Any) -> bool:
    return value is None or isinstance(value, list) or value == []

from eval.workflow_bench.propposer_sandbox import SandboxError

try:
    snapshot = cache.prepare(task, repo=repo, resolved_sha=sha)
except SandboxError as exc:
    if "sandbox_dependencies must be a list" in str(exc):
        # wrap the value in a list, or omit the field
        raise
    raise

When it happens

Trigger: Task JSON has `"sandbox_dependencies": {"source": "a", "target": "b"}` (a single dict instead of a list of dicts), or `"sandbox_dependencies": "node_modules"` (a bare string), or any non-list scalar. The check is `if not isinstance(raw_declarations, list)`.

Common situations: Author writes a single dependency as a dict instead of wrapping it in a list. Schema drift from a tool that emits a single object for a one-element array. Copy-paste from a config format that allows a bare value.

Related errors

• sandbox_dependencies entries require only nonblank source an
• sandbox_copy must be a list of nonblank repository-relative
• dependency source must stay inside the repository: {source_p
• dependency target must stay inside the clone: {target_path}
• sandbox dependency targets overlap: {declaration.target} and

AI-assisted analysis of abhigyanpatwari/GitNexus@d540b00184 (2026-08-12). Data as JSON: /api/errors/7e1538069165dd0c. Report an issue: GitHub.