Call this FIRST when you need a bank code, or when the user asks 'which central banks do you cover?' or 'do you have rates from X?'. Returns { banks: [{ code, name, country, home_ccy, rate_types, latest date, ... }], disclaimer } for 60+ institutions — central banks (ECB, Fed, BOJ, ...) plus tax authorities (HMRC, US Treasury, ...). The code field is what every other tool takes as its bank parameter. Cheap to call.

Use this for OFFICIAL rates a specific institution published — 'what is the ECB rate for USD?', 'Bank of Japan official rate on 2026-03-14', 'HMRC rate for invoicing'. These are the fixed rates in force for compliance, tax, customs, and accounting — NOT live market rates. Omit date for the newest published table; give date (paid plans) for the table in force on that day (weekends/holidays roll back to the last published date — the response's rate_date says which). Omit source/target for the bank's full table { rates: [{ base, quote, type, value }] }; give both for one pair — cross-computed via the bank's own home currency when not directly published, flagged derived. For live mid-market rates use the @allratestoday/mcp-server package instead.

Use this for a date-by-date series of one bank's OFFICIAL rates — 'ECB USD rate for every day of 2025', 'how did the CBSL official rate move last quarter'. Returns one row per published date: { series: [{ date, rate, rate_type, derived, method }] }. Give either symbol (matches either side of the pair vs the bank's home currency) or a source+target pair. Defaults to the last year when from/to omitted. Paid plans only, and BILLED BY VOLUME: one API call per month of history covered (a year-long series costs ~12 calls) — keep ranges as narrow as the question needs. For publication dates without values (free) use get_publication_calendar.

Use this when the user wants one currency pair across ALL institutions at once — 'what does each central bank say USD/EUR is?', 'spread between official USD/LKR rates', 'which bank has the highest official rate for X?'. One call returns every covered bank's latest official rate for the pair plus spread stats { min, max, median, spread_bps } over fresh sources (stale quarterly publishers are returned but excluded from stats). Rates a bank doesn't publish directly are cross-computed within that bank's own table only — banks are never mixed. Methodology: https://allratestoday.com/official-rates-methodology/

Use this to see WHICH dates a bank actually published a rate table — 'did the ECB publish on 2026-01-01?', 'how often does the US Treasury publish?'. Returns dates only, no rate values, so it is available on every plan (unlike history). Gaps reveal weekends, holidays, and weekly/quarterly publication cadence. Give ?year=YYYY or a from/to range; large ranges are capped and flagged truncated.