Free Data Quality API

What the quality API checks

Every report audits the dataset for structural and market-data problems:

The score starts at 100 and deducts points for critical errors and warnings. A critical issue can cap the grade at F. The report exposes the issue list rather than hiding it behind a single number.

Quality API response

Pass symbol and tf to the quality endpoint. The response includes:

Use the HTML report for a human-readable breakdown: all 617 quality reports.

How to read the A-F grades

• A: structurally clean with no material issues; minor warnings may still exist.
• B: good overall, with a small number of warnings worth reviewing.
• C: inspect gaps, volume or spread issues before production use.
• D: significant issues; use only after targeted cleaning.
• F: critical issues present; do not use blindly.

The exact grade uses the weighted score plus issue severity, so two datasets with a similar score can receive different grades. A high score does not guarantee profitable backtests; it means the file is structurally cleaner, not that the strategy or broker execution is good.

When to call the quality API

Quality API limits

The quality endpoint shares the public rate limit: 60 requests per minute and 1,000 requests per day per IP. It returns JSON only. The full report download is available from each HTML report page.

Request examples

curl "https://www.algospecial.com/api/data-quality.php?symbol=XAUUSD&tf=M15"

import requests

r = requests.get(
    "https://www.algospecial.com/api/data-quality.php",
    params={"symbol": "XAUUSD", "tf": "M15"},
    timeout=30,
)
r.raise_for_status()
report = r.json()

if report["grade"] in ("D", "F") or report["critical_count"] > 0:
    raise SystemExit("Dataset needs cleaning before backtesting")

print(report["score"], report["grade"], report["report_url"])

All timestamps are broker server time. Some legacy forex exports return 0 for TickVolume and Spread because those fields were not present in the source feed.

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