Data sources

Coinbase Exchange's public market data, relayed unread. No key is asked for because none is needed — these paths are open, and nothing here can reach an account. A candle row is `[time, low, high, open, close, volume]`: low and high come before open and close, which is not the order most vendors use, and rows arrive newest first. Buckets start at 00:00 UTC and a 24-hour market has no close, so which bucket counts as finished is the caller's convention to state. At most 300 candles answer one call. `ticker`, `stats`, `book` and `trades` take no date and are always now.

금융위원회's 증권상품시세정보, relayed unread — the Korea Exchange's own ETF, ETN and ELW numbers by way of 공공데이터포털. `clpr` is the traded close and is not adjusted, and neither `nav` nor `indcVal` is back-adjusted, so no series here is a total return: a distribution leaves a step in all of them. What this is for is what a price feed lacks — assets against price, the underlying against both, and how big the fund is. Dates are the caller's: `basDt` is one day, `beginBasDt`/`endBasDt` a range, and nothing is bounded by asOf. History begins 2020-01-02. An error arrives as `resultCode` on a 200.

OpenDART's own endpoints, relayed unread. A filing becomes public at its receipt — `rcept_no` begins with the receipt date and `rcept_dt` repeats it — and nothing here is bounded by `asOf`: reading those fields and dropping later rows is the caller's work. A period end is not a disclosure date, and a preliminary announcement and the periodic report that restates it are two filings with two receipts; `report_nm` and `pblntf_ty` tell them apart. `corpCode.xml` answers with a ZIP. The investor's key is appended as `crtfc_key`, never shown to a manager. Errors arrive as `status` on a 200.

Reads an OpenBB Platform you run yourself, asking FMP for unadjusted bars. The provider is a query parameter here rather than a pinned value, because nothing maps the answer any more — which provider answered is visible in the response, and it is the caller who decides whether that is the one they wanted. Nothing is bounded by asOf.

SEC EDGAR's own endpoints, relayed unread. The `{symbol}` segment of `companyfacts` is a filename and not a ticker: it must be `CIK` + the ten-digit zero-padded CIK + `.json` (`CIK0000050863.json`), and a ticker there answers 404. So `/files/company_tickers.json` is a precondition of this path and not only a mapping table; its `cik_str` is an integer the caller pads. `companyfacts` is a filer's whole XBRL history; nothing here is bounded by asOf and nothing is dated by Aumos, so reading the filing dates out is the caller's work. SEC requires a contactable caller; that is the credential.