exchange-rates-mcp-server

<div align="center">
  <h1>@cyanheads/exchange-rates-mcp-server</h1>
  <p><b>Convert currencies, get FX rates, and query historical ECB exchange rate data via MCP. STDIO or Streamable HTTP.</b>
  <div>7 Tools • 1 Opt-in Tool • 2 Resources</div>
  </p>
</div>

<div align="center">

[![Version](https://img.shields.io/badge/Version-0.4.0-blue.svg?style=flat-square)](./CHANGELOG.md) [![License](https://img.shields.io/badge/License-Apache%202.0-orange.svg?style=flat-square)](./LICENSE) [![Docker](https://img.shields.io/badge/Docker-ghcr.io-2496ED?style=flat-square&logo=docker&logoColor=white)](https://github.com/users/cyanheads/packages/container/package/exchange-rates-mcp-server) [![MCP SDK](https://img.shields.io/badge/MCP%20SDK-^2.0.0-green.svg?style=flat-square)](https://modelcontextprotocol.io/) [![npm](https://img.shields.io/npm/v/@cyanheads/exchange-rates-mcp-server?style=flat-square&logo=npm&logoColor=white)](https://www.npmjs.com/package/@cyanheads/exchange-rates-mcp-server) [![TypeScript](https://img.shields.io/badge/TypeScript-^7.0.2-3178C6.svg?style=flat-square)](https://www.typescriptlang.org/) [![Bun](https://img.shields.io/badge/Bun-v1.4.0-blueviolet.svg?style=flat-square)](https://bun.sh/)

</div>

<div align="center">

[![Install in Claude Desktop](https://img.shields.io/badge/Install_in-Claude_Desktop-D97757?style=for-the-badge&logo=anthropic&logoColor=white)](https://github.com/cyanheads/exchange-rates-mcp-server/releases/latest/download/exchange-rates-mcp-server.mcpb) [![Install in Cursor](https://cursor.com/deeplink/mcp-install-dark.svg)](https://cursor.com/en/install-mcp?name=exchange-rates-mcp-server&config=eyJjb21tYW5kIjoibnB4IiwiYXJncyI6WyIteSIsIkBjeWFuaGVhZHMvZXhjaGFuZ2UtcmF0ZXMtbWNwLXNlcnZlciJdfQ==) [![Install in VS Code](https://img.shields.io/badge/VS_Code-Install_Server-0098FF?style=for-the-badge&logo=visualstudiocode&logoColor=white)](https://vscode.dev/redirect?url=vscode:mcp/install?%7B%22name%22%3A%22exchange-rates-mcp-server%22%2C%22command%22%3A%22npx%22%2C%22args%22%3A%5B%22-y%22%2C%22%40cyanheads%2Fexchange-rates-mcp-server%22%5D%7D)

[![Framework](https://img.shields.io/badge/Built%20on-@cyanheads/mcp--ts--core-67E8F9?style=flat-square)](https://www.npmjs.com/package/@cyanheads/mcp-ts-core)

</div>

<div align="center">

**Public Hosted Server:** [https://exchange-rates.caseyjhand.com/mcp](https://exchange-rates.caseyjhand.com/mcp)

</div>

---

## Tools

Eight tools for working with ECB FX rate data — currency lookup and disambiguation, point-in-time rates and conversions, historical time-series retrieval, and SQL analytics over the DataCanvas workspace that long time-series calls produce. Five are advertised by default; the three `fx_dataframe_*` tools need `CANVAS_PROVIDER_TYPE=duckdb`, and the destructive one among them additionally needs `FX_ENABLE_CANVAS_DROP=true`.

The three `fx_dataframe_*` tools require DataCanvas. With `CANVAS_PROVIDER_TYPE` unset (the default) they are not advertised in `tools/list` at all, so a client never sees a tool it cannot call; the HTTP landing page still lists them as disabled cards hinting `CANVAS_PROVIDER_TYPE=duckdb`, so operators can tell they exist. In that mode `fx_get_timeseries` returns every range inline, paged at 500 publication days:

| Tool | Description |
|:-----|:------------|
| `fx_list_currencies` | List all ~30 ECB-supported ISO 4217 currencies with full names. Use before converting to disambiguate "dollars" (USD vs AUD vs CAD vs HKD vs SGD). |
| `fx_get_rates` | Snapshot of all available rates for a base currency at latest or a historical date. Surfaces `date_snapped` when a weekend/holiday request returns the prior business-day snapshot. Optional `symbols` filter for smaller responses; listing the base itself returns a rate of 1 for it. |
| `fx_get_rate` | Exchange rate for a single currency pair at latest or a historical date. Surfaces `date_snapped` when a weekend/holiday request returns the prior business-day rate. |
| `fx_convert_currency` | Convert an amount between any two currencies at latest or a historical rate. Cross-rates are triangulated through EUR. Returns converted amount, rate used, rate date, and whether the date was snapped. |
| `fx_get_timeseries` | Historical daily rates for a currency pair over a date range, never including a date outside it. Inline results come back in pages of 500 publication days, continued with `next_start_date`; when DataCanvas is enabled, long ranges (>90 days) spill to it with a `canvas_id` for SQL follow-up instead. |
| `fx_dataframe_describe` | List DataCanvas tables and their columns from a prior `fx_get_timeseries` call. Required first step before `fx_dataframe_query`. Needs `CANVAS_PROVIDER_TYPE=duckdb`. |
| `fx_dataframe_query` | Run a read-only SQL SELECT against a DataCanvas table produced by `fx_get_timeseries`. Supports aggregations, GROUP BY, window functions, and JOINs across multiple registered tables. Returns at most `row_limit` rows (default 150, max 10,000). Needs `CANVAS_PROVIDER_TYPE=duckdb`. |
| `fx_dataframe_drop` | Permanently remove one staged table or view from a DataCanvas. Deletes staged analytical data only — ECB rate data is untouched and the series can be re-staged. Needs `CANVAS_PROVIDER_TYPE=duckdb` and `FX_ENABLE_CANVAS_DROP=true`; disabled otherwise. |

### `fx_list_currencies`

Enumerate all supported currencies before converting or querying.

- Returns `[{ code, name }]` for all ~30 ECB-scoped currencies
- ECB coverage fluctuates as currencies enter/exit scope — always call this tool to validate user-supplied codes rather than hard-coding a list

---

### `fx_get_rates`

Full rates snapshot for a base currency in one call.

- Returns all available quote currencies at a given date (default: latest), the actual `rate_date`, and `date_snapped: true` when the API silently moved a weekend/holiday request to the prior business day — always `false` when `date` is omitted
- Optional `symbols` parameter narrows the response to specific quote currencies; when sent it must name at least one code — omit it to get every currency
- Naming the base currency in `symbols` is valid — it is answered locally with a rate of 1 rather than sent upstream, which keeps a self-quote from failing
- Useful for seeding bulk comparison workflows or discovering what's available

---

### `fx_get_rate`

Point-in-time exchange rate for a single pair.

- Returns the rate, the actual rate date, and `date_snapped: true` when the API silently moved a weekend/holiday request to the prior business day
- Cross-rates (neither side EUR) are triangulated in a single API call — no extra round trip
- A same-currency pair returns a rate of 1 without a self-quote reaching the API, but still reports the publication date the ECB actually had for that currency, so `rate_date` and `date_snapped` read the same as for any other pair
- Use `fx_convert_currency` when you need the converted amount; use this tool when you only need the rate number

---

### `fx_convert_currency`

Convert an amount between any two currencies.

- Handles EUR ↔ any, any ↔ EUR, and cross-rate (USD → JPY via EUR) in one upstream call
- Returns `quote_amount`, `rate`, `rate_date`, `date_snapped`, plus `rate_type` and `source` provenance on every response
- Historical conversions supported back to 1999-01-04 (ECB launch date)

---

### `fx_get_timeseries` + `fx_dataframe_describe` / `fx_dataframe_query`

Historical rate series and DataCanvas SQL analytics.

`fx_get_timeseries` returns a date-keyed series (business days only — ECB publishes once per business day):

- Short ranges (≤ `FX_TIMESERIES_CANVAS_THRESHOLD_DAYS`, default 90 days) → inline `rates` map + metadata
- Long ranges, **when DataCanvas is enabled** → a preview inline + `canvas_id`, `table_name`, `spilled: true`, and a `notice` naming `fx_dataframe_describe` then `fx_dataframe_query` — the full series is registered as a DuckDB-backed table
- Long ranges **without DataCanvas** → returned inline with `spilled: false`, paged (below), and a `notice` saying the threshold was crossed but no canvas was configured
- Inline results are paged at 500 publication days. `rate_count` is always the total for the requested range; when a page is cut short the response carries `truncated: true` and `next_start_date`. Call again with `start_date` set to `next_start_date` and the same `end_date` for the next page — the final page has `truncated: false` and no `next_start_date`
- Requesting the same currency on both sides returns a rate of 1 on each publication day in the range, taken from the ECB's real calendar rather than a synthetic Mon–Fri loop

The response never carries a date outside the requested range. Frankfurter snaps a range that opens on a weekend or bank holiday back to the prior publication day; those rows are dropped, so `start_date` and `end_date` always sit inside the window you asked for. A range covering only non-publication days therefore returns an empty `rates` map with `rate_count: 0` and a `notice` explaining that the ECB published nothing in that window — distinguishable from an error.

Once a `canvas_id` is in hand:

1. **`fx_dataframe_describe`** — list the tables and columns on the canvas (required before `fx_dataframe_query`)
2. **`fx_dataframe_query`** — run arbitrary SQL SELECT against the registered table; supports aggregations, GROUP BY, window functions, JOINs across tables from multiple `fx_get_timeseries` calls. Returns at most `row_limit` rows (default 150, max 10,000) on both response surfaces; past that, `truncated: true` and a `notice` give the `ORDER BY <column> LIMIT <n> OFFSET <m>` shape for the next page (`ORDER BY` is required for stable paging). Cell values are escaped in the Markdown table so pipes, angle brackets, and line breaks stay inside their cell; `structuredContent` keeps the raw values

The canvas uses a session-scoped TTL. To continue working with a prior series, call `fx_get_timeseries` again with the same parameters to