deepset-ai/haystack · error · FilterError

'conditions' key missing in {condition}

Error message

'conditions' key missing in {condition}

What it means

A logical filter condition must include a 'conditions' key holding the list of sub-conditions. If 'operator' exists but 'conditions' is missing, _logic_condition raises this FilterError.

Source

Thrown at haystack/utils/filters.py:275

    "!=": _not_equal,
    ">": _greater_than,
    ">=": _greater_than_equal,
    "<": _less_than,
    "<=": _less_than_equal,
    "in": _in,
    "not in": _not_in,
}


def _logic_condition(
    condition: dict[str, Any], document: Document | ByteStream, strict_datetime_comparison: bool
) -> bool:
    if "operator" not in condition:
        msg = f"'operator' key missing in {condition}"
        raise FilterError(msg)
    if "conditions" not in condition:
        msg = f"'conditions' key missing in {condition}"
        raise FilterError(msg)
    operator: str = condition["operator"]
    if operator not in LOGICAL_OPERATORS:
        msg = f"Unknown logical operator '{operator}'. Valid operators are: {sorted(LOGICAL_OPERATORS)}"
        raise FilterError(msg)
    conditions: list[dict[str, Any]] = condition["conditions"]
    return LOGICAL_OPERATORS[operator](
        document=document, conditions=conditions, strict_datetime_comparison=strict_datetime_comparison
    )


def _comparison_condition(
    condition: dict[str, Any], document: Document | ByteStream, strict_datetime_comparison: bool
) -> bool:
    if "field" not in condition:
        # 'field' key is only found in comparison dictionaries.
        # We assume this is a logic dictionary since it's not present.
        return _logic_condition(
            condition=condition, document=document, strict_datetime_comparison=strict_datetime_comparison

View on GitHub (pinned to e318778c9b)

Solutions

1. Add a "conditions" key containing a list of condition dicts.
2. Fix key typos (must be exactly 'conditions').
3. Build filters via the documented schema and validate nested lists before applying.

Example fix

// before
filters = {"operator": "AND", "condition": [{"field": "meta.x", "operator": "==", "value": 1}]}
// after
filters = {"operator": "AND", "conditions": [{"field": "meta.x", "operator": "==", "value": 1}]}

assert "conditions" in condition, f"logical condition needs 'conditions' list: {condition}"

def has_conditions(c: dict) -> bool:
    return isinstance(c.get("conditions"), list) and len(c["conditions"]) > 0

try:
    ok = document_matches_filter(doc, filters)
except FilterError as e:
    raise ValueError(f"malformed filter: {e}") from e

When it happens

Trigger: Passing {"operator": "AND"} with no 'conditions' list, or a condition whose sub-conditions were stored under another key name.

Common situations: Typos like 'condition' or 'filters' instead of 'conditions'; partially constructed filters; deserialized configs with a wrong schema version.

Related errors

• 'operator' key missing in {condition}
• Filter value can't be of type {type(filter_value)} using ope
• Can't compare strings using operators '>', '>=', '<', '<='.
• Filter value must be a `list` when using operator 'in' or 'n
• Unknown logical operator '{operator}'. Valid operators are:

AI-assisted analysis of deepset-ai/haystack@e318778c9b (2026-08-30). Data as JSON: /api/errors/dc345d4e552cf613. Report an issue: GitHub.