sgl-project/sglang · error · ValueError

MiniMax H3 task must be a non-empty string

Error message

MiniMax H3 task must be a non-empty string

What it means

partition_for_task validates its task argument: it must be a Python str (not None or another type) and must contain non-whitespace content. This is the first gate before task normalization and partition lookup, so non-string or blank inputs fail fast with a clear message.

Source

Thrown at python/sglang/multimodal_gen/runtime/pipelines_core/stages/model_specific_stages/minimax_h3/task_profiles.py:51

    {
        "t2va": "fl2va",
        "fl2va": "fl2va",
        "ref2va": "ref2va",
    }
)


def canonical_minimax_h3_task(task: str) -> str:
    """Normalize a public task name (no aliases are currently defined)."""

    return task


def partition_for_task(task: str) -> str:
    """Return the deployment partition serving *task*."""

    if not isinstance(task, str) or not task.strip():
        raise ValueError("MiniMax H3 task must be a non-empty string")
    normalized = task.strip().lower()
    try:
        return MINIMAX_H3_TASK_PARTITIONS[normalized]
    except KeyError as exc:
        raise ValueError(f"unsupported MiniMax H3 task {task!r}") from exc


MINIMAX_H3_FINITE_ASPECT_RATIOS = (
    "21:9",
    "16:9",
    "4:3",
    "1:1",
    "3:4",
    "9:16",
)

# ``fl2va`` remains the single public task name for all keyframe variants:
# first-frame-only, last-frame-only, and first+last.  Keep the accepted

View on GitHub (pinned to 0132848349)

Solutions

1. Set a valid task string (e.g. 't2va', 'fl2va', 'ref2va') in your config/request
2. Default the field explicitly instead of leaving it None
3. Strip/validate user input before passing it to partition_for_task

Example fix

# before
task = config.get("task")
partition = partition_for_task(task)

# after
task = (config.get("task") or "").strip().lower()
if not task:
    raise ValueError("config must set 'task'")
partition = partition_for_task(task)

task = (raw_task or "").strip() if isinstance(raw_task, str) else ""
if not task:
    raise ValueError("'task' must be a non-empty string")
partition = partition_for_task(task)

def is_nonempty_task(task: Any) -> bool:
    return isinstance(task, str) and bool(task.strip())

catch ValueError around partition_for_task and map it to a 400-level config error

When it happens

Trigger: Calling partition_for_task(None), partition_for_task(''), partition_for_task(' '), or passing an int/dict instead of a string. Also hit when the task comes from an unvalidated config field that defaults to None.

Common situations: Reading task from CLI args or YAML config where it was omitted; a caller passing task.get('task') on a dict without the key; API requests missing the task field.

Understand the failure class

Background: Missing required parameter errors: what 'X is required' and 'the required X param is missing' mean, and how to fix them — this error's family across 27 libraries.

Related errors

• ref2va keyframes require at least one reference condition; u
• task {plan.task!r} cannot carry image.target_canvas material
• unsupported MiniMax H3 task {task!r}
• MiniMax H3 shift_scale must be > 0
• MiniMax H3 num_steps must be > 0

AI-assisted analysis of sgl-project/sglang@0132848349 (2026-08-28). Data as JSON: /api/errors/009749e9d3bcc116. Report an issue: GitHub.