exchange-rates-mcp-server

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  <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 • 2 Resources</div>
  </p>
</div>

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[![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)

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

</div>

---

## Tools

Seven 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:

| 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. Optional `symbols` filter for smaller responses. |
| `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. Short ranges (≤90 days) are returned inline; long ranges spill to DataCanvas with a `canvas_id` for SQL follow-up. |
| `fx_dataframe_describe` | List DataCanvas tables and their columns from a prior `fx_get_timeseries` call. Required first step before `fx_dataframe_query`. |
| `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. |

### `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)
- Optional `symbols` parameter narrows the response to specific quote currencies
- 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
- 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 `converted_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 → first N rows inline + `canvas_id`, `table_name`, and `truncated: true` — the full series is registered as a DuckDB-backed table

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

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

---

## Resources and prompts

| Type | Name | Description |
|:-----|:-----|:------------|
| Resource | `fx://currencies` | All supported currencies as a stable reference document. Injectable context for clients that support resources. |
| Resource | `fx://rates/latest/{base}` | Latest rates snapshot for a base currency as a stable URI. |

All resource data is also reachable via tools. Use `fx_list_currencies` or `fx_get_rates` for programmatic access.

---

## Features

Built on [`@cyanheads/mcp-ts-core`](https://www.npmjs.com/package/@cyanheads/mcp-ts-core):

- Declarative tool and resource definitions — single file per primitive, framework handles registration and validation
- Unified error handling — handlers throw, framework catches, classifies, and formats
- Typed error contracts with recovery hints — `unsupported_currency`, `date_out_of_range`, `canvas_not_found`, `invalid_query`
- Pluggable auth: `none`, `jwt`, `oauth`
- Structured logging with optional OpenTelemetry tracing
- STDIO and Streamable HTTP transports

ECB FX–specific:

- Keyless access via [Frankfurter](https://www.frankfurter.dev/) — a Cloudflare-fronted ECB proxy; no API keys required
- Cross-rate triangulation: any pair works (USD → JPY fetches EUR/USD and EUR/JPY in one call, computes JPY/USD ratio)
- Weekend/holiday date semantics: `date_snapped` flag surfaces when the API returns a different date than requested
- ECB data covers ~30 major currencies from 1999-01-04 to present; `fx_list_currencies` always reflects the live set
- DataCanvas integration: `fx_get_timeseries` spills long ranges to DuckDB for aggregations and trend analysis
- Rate provenance on every response: `rate_type: "ECB reference (mid-market)"` and `source: "ECB via Frankfurter"` — explicitly mid-market, not tradeable bid/ask

Agent-friendly output:

- Rate provenance on every response — `rate_type`, `source`, `rate_date`, and `date_snapped` so agents can reason about trust and freshness
- Structured error contracts — typed `reason` fields (`unsupported_currency`, `date_out_of_range`, `invalid_query`, …) let callers branch on failure type, not string parsing
- Discriminated DataCanvas output — `canvas_id` and `truncated: true` signal when a time-series exceeds the inline limit and SQL follow-up is needed

---

## Getting started

### Public Hosted Instance

A public instance is available at `https://exchange-rates.caseyjhand.com/mcp` — no installation required. Point any MCP client at it via Streamable HTTP:

```json
{
  "mcpServers": {
    "exchange-rates-mcp-server": {
      "type": "streamable-http",
      "url": "https://exchange-rates.caseyjhand.com/mcp"
    }
  }
}
```

### Self-Hosted / Local

No API key required — Frankfurter is keyless. Add the following to your MCP client configuration file:

```json
{
  "mcpServers": {
    "exchange-rates-mcp-server": {
      "type": "stdio",
      "command": "bunx",
      "args": ["@cyanheads/exchange-rates-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "MCP_LOG_LEVEL": "info"
      }
    }
  }
}
```

Or with npx (no Bun required):

```json
{
  "mcpServers": {
    "exchange-rates-mcp-server": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@cyanheads/exchange-rates-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "MCP_LOG_LEVEL": "info"
      }
    }
  }
}
```

Or with Docker:

```json
{
  "mcpServers": {
    "exchange-rates-mcp-server": {
      "type": "stdio",
      "command": "docker",
      "args": [
        "run", "-i"