Twelve Data

Use in your agent

Load Twelve Data daily prices into pandas and Parquet for testing. Checked against the provider's documentation on Oct 29, 2026.

Access

• A Basic API key is required. Put it in TWELVE_DATA_API_KEY.
• Free data is for internal testing, evaluation or development only.

Request

curl 'https://api.twelvedata.com/time_series?symbol=AAPL&interval=1day&outputsize=100&apikey='$TWELVE_DATA_API_KEY

Format

JSON: status and metadata plus values in reverse chronological order. OHLC and volume values are strings.

Load into pandas and Parquet

Needs Python 3 with requests, pandas and pyarrow.

"""Twelve Data daily AAPL prices -> pandas -> Parquet. Free tier testing only."""
import os
import requests
import pandas as pd

params = {"symbol": "AAPL", "interval": "1day", "outputsize": 100,
          "apikey": os.environ["TWELVE_DATA_API_KEY"]}
r = requests.get("https://api.twelvedata.com/time_series", params=params, timeout=30)
r.raise_for_status()
body = r.json()
if body.get("status") == "error":
    raise RuntimeError(body["message"])
df = pd.DataFrame(body["values"])
df["datetime"] = pd.to_datetime(df["datetime"])
for column in ("open", "high", "low", "close", "volume"):
    df[column] = pd.to_numeric(df[column])
df = df.sort_values("datetime")
df.to_parquet("twelve_data_aapl_daily.parquet", index=False)
print(len(df), "rows", df["datetime"].min().date(), "to", df["datetime"].max().date())

Needs a personal API key; not run.

Limits

• Basic: eight API credits per minute and 800 credits per day.
• Credits are weighted by endpoint and symbol count.

Quirks

• Sort values by datetime before time-series work.
• An API error is a JSON object with status=error, code and message.
• The free plan is not for display or production.

Terms and attribution

• Basic data may be used internally only for testing, evaluation or development.
• It may not be displayed, shared externally or used in production.
• Free-tier data may not be used commercially.

Sources

• https://twelvedata.com/pricing: “8 (800 a day)”
• https://twelvedata.com/pricing: “Data may be used internally for testing, evaluation, or development purposes only.”
• https://twelvedata.com/terms: “Use Free Tier data for commercial purposes”