Why can't I get full historical data from this API?

There are a few common reasons an API won’t give you “full historical data,” even if it looks like it should:

1. Built-in data retention limits

   • The provider may only store or expose a certain window of history (e.g., last 30 days, 1 year, 5 years).
   • Older data may exist internally but not be available through the public API.

2. Subscription / plan restrictions

   • Full history may be reserved for paid tiers or enterprise access.
   • Free or lower-tier plans often return only recent or limited records.

3. Endpoint-specific limits

   • Some endpoints only support recent data or aggregated snapshots, not full raw history.
   • “Historical” might mean candle/bar data, while tick-level history is unavailable.

4. Pagination or max-record limits

   • APIs often cap results per request.
   • If you don’t paginate properly, you’ll only get the first batch and think the history is missing.

5. Date-range constraints

   • The API may require you to query in chunks.
   • Some APIs reject very large ranges or silently truncate them.

6. Rate limiting / throttling

   • If you request too much too quickly, the API may return partial results or errors.
   • You might need to slow down or add retries.

7. Data availability / licensing

   • Historical data can be limited by exchange rules, market licensing, or source-provider agreements.
   • Certain regions, instruments, or time periods may be unavailable.

8. Timezone / parameter issues

   • If you pass incorrect timestamps, the API may return a smaller range than expected.
   • Off-by-one errors in start/end dates are very common.

9. Gaps in source data

   • The provider may simply not have older data for certain assets, symbols, or markets.

If you want, paste:

• the API name,
• the endpoint you’re calling,
• your request parameters,
• and a sample response,

and I can help pinpoint the exact reason.