OpenBB-finance/OpenBB · warning · EmptyDataError

The request was returned empty.

Error message

The request was returned empty.

What it means

Raised by FREDCommercialPaperFetch.transform_data when the fetched payload dict is falsy - the FRED series request backing commercial paper rates (CP_SERIES_IDS symbols) returned nothing before the melt/rename pipeline could run. Note the transform then indexes CP_SERIES_IDS by each symbol, so any non-empty but partial payload would instead KeyError.

Source

Thrown at openbb_platform/providers/fred/openbb_fred/models/commercial_paper.py:339

            raise e from e

        return {
            "metadata": response.metadata,
            "data": [d.model_dump() for d in response.result],
        }

    @staticmethod
    def transform_data(
        query: FREDCommercialPaperParams,
        data: dict,
        **kwargs: Any,
    ) -> list[FREDCommercialPaperData]:
        """Transform data."""
        # pylint: disable=import-outside-toplevel
        from pandas import Categorical, DataFrame

        if not data:
            raise EmptyDataError("The request was returned empty.")
        df = DataFrame(data["data"])
        metadata = data.get("metadata", {})
        # Flatten data
        df = df.melt(id_vars="date", var_name="symbol", value_name="value").query(
            "value.notnull()"
        )
        df = df.rename(columns={"value": "rate"}).sort_values(by="date")
        # Normalize percent values
        df["rate"] = df["rate"].astype(float) / 100
        # Add asset type, maturity, and title
        df["asset_type"] = df["symbol"].apply(lambda x: CP_SERIES_IDS[x]["asset"])
        df["title"] = df["symbol"].apply(lambda x: CP_SERIES_IDS[x]["title"])
        df["maturity"] = df["symbol"].apply(lambda x: CP_SERIES_IDS[x]["maturity"])
        # Categorize and order.
        asset_type_categories = ["asset_backed", "financial", "nonfinancial", "a2p2"]
        maturity_categories = [
            "overnight",
            "day_7",

View on GitHub (pinned to 3e071fcc2c)

Solutions

1. Verify the FRED API key is set and valid (test against fred.stlouisfed.org with a simple series like DFF)
2. Remove date filters to request full series history
3. Check which CP series in CP_SERIES_IDS are still published on FRED and whether your window predates/postdates them
4. Retry after a minute if FRED throttled the request

import os, requests
key = os.environ.get('FRED_API_KEY')
assert key, 'FRED_API_KEY not set'
r = requests.get(f'https://api.stlouisfed.org/fred/series/observations?series_id=CPFF&api_key={key}&file_type=json')
assert r.status_code == 200 and r.json().get('observations'), 'FRED key or series invalid'

def is_non_empty_payload(payload: object) -> bool:
    return isinstance(payload, dict) and len(payload) > 0

from openbb_core.provider.utils.errors import EmptyDataError
try:
    obs = await obb.fixedincome.commercial_paper(provider='fred', start_date=s, end_date=e).await_to_list()
except EmptyDataError:
    obs = []

When it happens

Trigger: FRED returning {} for the commercial paper series request - invalid/expired FRED API key producing an empty structure, or a complete failure of the underlying multi-series fetch with no observations for the date window.

Common situations: Misconfigured FRED_API_KEY (empty-key requests can yield empty bodies rather than explicit errors); date windows outside the CP series' coverage (some tenors were discontinued in 2020); FRED request throttling.

Related errors

• No data returned for the given symbols.
• The request was returned empty.
• No data was returned from the FMP endpoint.
• The request was returned with no data.
• No data was found for, {query.country}.

AI-assisted analysis of OpenBB-finance/OpenBB@3e071fcc2c (2026-08-14). Data as JSON: /api/errors/c7a9187449b58d90. Report an issue: GitHub.