ECB reference rates with the rate date on every answer. It caches the European Central Bank's daily and historical euro reference rates, converts between any currencies the ECB quotes through EUR cross rates, and emits the exact fx_rates object the expense tracker needs to rebill a project in one currency.
If you invoice one client per repository, put the currency server in that project's .cursor/mcp.json next to the expense tracker, and the pair that rebills in the client's currency is scoped to the client's project.
| You say | Tool |
|---|---|
| What is 4,500 EUR in USD today? | convert |
| What was the GBP rate on 30 August? | rate_on |
| Rebill Nova in USD using today's rates. | fx_rates_for then expense_to_invoice |
Counted from the published history file: the ECB series runs 1999-01-04 to 2026-09-02, 10,104 calendar days holding 7,084 dates, so 29.9% of dates carry no rate. Every answer names the rate date it actually used.
The file is .cursor/mcp.json, and the key inside it is mcpServers.
| Scope | Path |
|---|---|
| This project only | <project>/.cursor/mcp.json |
| Every project | ~/.cursor/mcp.json |
{
"mcpServers": {
"currency": {
"type": "stdio",
"command": "npx",
"args": ["-y", "@theluckystrike/mcp-currency"]
}
}
}The Customize page shows the server and its tools once it has started.
The npm publish of @theluckystrike/mcp-currency is pending; until then use the .mcpb bundle or a clone and build from the latest release.
There is no hosted endpoint for this one yet. MCP Currency Converter runs locally over stdio with the config above, which is also the only form in which it reads and writes files on your own disk. Three of the servers in this collection are served at https://mcp.zovo.one/mcp/<name> over MCP streamable HTTP: time-tracker, price-tracker and invoice.
The current field table marks `type` as required, with `stdio` for a locally launched server, so write it out rather than relying on command and args alone. The other documented restriction is that `envFile` is stdio-only: a remote HTTP or SSE server does not read it, and its headers belong in the config.
Free: latest rates, convert, convert_many, fx_rates_for, history windows up to 90 days. Pro is $19 once, verified offline.
<project>/.cursor/mcp.json applies to that project and can be committed, which suits a server tied to one client. ~/.cursor/mcp.json applies everywhere. Both are managed from the Customize page.
The current field table marks type as required, with stdio for a locally launched server, so include it. Pointing at a remote endpoint, envFile is documented as stdio-only and is not read.
Servers in Cursor's marketplace get an Add to Cursor button. The deeplink reference currently documents prompt, command and rule links only, so for MCP Currency Converter pasting the config block above is the supported route.
MCP Currency Converter in detail · The same server in Claude Code and VS Code · Every server in Cursor · Guides · Cursor docs