chroma-core/chroma · error · TypeError

{op} keys must be a list, got {type(keys).__name__}

Error message

{op} keys must be a list, got {type(keys).__name__}

What it means

Error "{op} keys must be a list, got {type(keys).__name__}" thrown in chroma-core/chroma.

Source

Thrown at chromadb/execution/expression/operator.py:1365

    Returns:
        Tuple of (keys, k) where keys is List[Union[Key, str]] and k is int

    Raises:
        TypeError: If data types are invalid
        ValueError: If required fields are missing or invalid
    """
    agg_data = data[op]
    if not isinstance(agg_data, dict):
        raise TypeError(f"{op} requires a dict, got {type(agg_data).__name__}")
    if "keys" not in agg_data:
        raise ValueError(f"{op} requires 'keys' field")
    if "k" not in agg_data:
        raise ValueError(f"{op} requires 'k' field")

    keys = agg_data["keys"]
    if not isinstance(keys, (list, tuple)):
        raise TypeError(f"{op} keys must be a list, got {type(keys).__name__}")
    if not keys:
        raise ValueError(f"{op} keys cannot be empty")

    k = agg_data["k"]
    if not isinstance(k, int):
        raise TypeError(f"{op} k must be an integer, got {type(k).__name__}")
    if k <= 0:
        raise ValueError(f"{op} k must be positive, got {k}")

    return _strings_to_keys(keys), k


@dataclass
class Aggregate:
    """Base class for aggregation expressions within groups.

    Aggregations determine which records to keep from each group:
    - MinK: Keep k records with minimum values (ascending order)

View on GitHub (pinned to aecdd12c8a)

When it happens

Trigger: Thrown at chromadb/execution/expression/operator.py:1365 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of chroma-core/chroma@aecdd12c8a (2026-08-16). Data as JSON: /api/errors/9a79f16cce544277. Report an issue: GitHub.