unslothai/unsloth · warning · ValueError

file_ids must not be empty

Error message

file_ids must not be empty

What it means

Pydantic model_validator error on SeedInspectUploadRequest when the multi-file mode is selected (file_ids present) but the list is empty. An empty upload has nothing to inspect, and distinguishing it here yields a clearer 422 than a downstream 'no files resolved' failure.

Source

Thrown at studio/backend/models/data_recipe.py:100

    file_ids: list[str] | None = None
    file_names: list[str] | None = None
    # Shared fields
    preview_size: int = Field(default = 10, ge = 1, le = 50)
    seed_source_type: str | None = None
    unstructured_chunk_size: int | None = Field(default = None, ge = 1, le = 20000)
    unstructured_chunk_overlap: int | None = Field(default = None, ge = 0, le = 20000)

    @model_validator(mode = "after")
    def _check_mutual_exclusivity(self) -> "SeedInspectUploadRequest":
        has_legacy = self.content_base64 is not None
        has_multi = self.file_ids is not None
        if has_legacy and has_multi:
            raise ValueError("Provide either content_base64 or file_ids, not both")
        if not has_legacy and not has_multi:
            raise ValueError("Provide either content_base64 or file_ids")
        if has_multi:
            if len(self.file_ids) == 0:
                raise ValueError("file_ids must not be empty")
            if not self.block_id:
                raise ValueError("block_id is required when using file_ids")
            if self.file_names is None or len(self.file_ids) != len(self.file_names):
                raise ValueError("file_names must be provided and same length as file_ids")
        if has_legacy:
            if not self.filename:
                raise ValueError("filename is required when using content_base64")
        return self


class SeedInspectResponse(BaseModel):
    dataset_name: str
    resolved_path: str
    columns: list[str] = Field(default_factory = list)
    preview_rows: list[dict[str, Any]] = Field(default_factory = list)
    split: str | None = None
    subset: str | None = None
    resolved_paths: list[str] | None = None

View on GitHub (pinned to 203007d190)

Solutions

1. Ensure file_ids contains at least one previously uploaded file id before calling the endpoint.
2. Disable the submit action in the UI until the selection is non-empty.
3. If the array is built dynamically, log its length right before the request to catch filter bugs.

Example fix

// before
{ "file_ids": [], "file_names": [], "block_id": "b1" }
// after
{ "file_ids": ["file-123"], "file_names": ["a.jsonl"], "block_id": "b1" }

def file_ids_valid(file_ids: list[str] | None) -> bool:
    return file_ids is None or len(file_ids) > 0

def is_nonempty_id_list(v: list[str] | None) -> bool:
    return v is None or (isinstance(v, list) and len(v) > 0)

When it happens

Trigger: POSTing {"file_ids": [], ...} — typically a client that initializes an empty selection array and submits before any files are picked, or a filter that removes all ids.

Common situations: UI allowing submit with zero selected files; a dedupe/filter step that empties the array; state reset bugs that clear the list but not the submit flag.

Related errors

• Provide either content_base64 or file_ids, not both
• Provide either content_base64 or file_ids
• block_id is required when using file_ids
• file_names must be provided and same length as file_ids
• filename is required when using content_base64

AI-assisted analysis of unslothai/unsloth@203007d190 (2026-08-15). Data as JSON: /api/errors/829f4650b0906d45. Report an issue: GitHub.