mcp-mexico

mcp-mexico

MCP server that gives AI agents official Mexican public data: Banxico exchange and interest rates, INEGI inflation, UMA values and ISR tax tables.

Leer en español

Claude Code using mcp-mexico. Response wait times are cut from the recording.

Why

AI assistants either make up Mexican economic figures or use stale ones, so you end up looking them up by hand at Banxico, INEGI or the SAT and pasting them in. mcp-mexico lets any MCP client (Claude Desktop, Claude Code, Cursor) fetch them directly. Every result names its official source and the date it applies to.

Tools

Tool	What it returns	Source	Token
get_fix_rate	FIX USD/MXN exchange rate, latest or for a date. On weekends and holidays it returns the previous business day.	Banxico SIE	BANXICO_TOKEN
get_fix_rate_range	Daily FIX between two dates (max 366 days).	Banxico SIE	BANXICO_TOKEN
get_interest_rate	Banxico target rate, 28-day TIIE, overnight TIIE de Fondeo or 28-day CETES; latest or for a date.	Banxico SIE	BANXICO_TOKEN
get_interest_rate_range	One of those rates between two dates (max 366 days).	Banxico SIE	BANXICO_TOKEN
get_inflation	INPC index and monthly, annual and year-to-date inflation for a month (latest by default).	INEGI	INEGI_TOKEN
get_inflation_range	The same for each month in a range (max 240 months).	INEGI	INEGI_TOKEN
get_uma	UMA daily, monthly and annual values, 2020–2026, with validity dates.	INEGI	none
get_isr_table	ISR tables for individuals, 2020–2026: monthly (LISR Art. 96) and annual (LISR Art. 152).	Anexo 8 of the RMF (SAT / DOF)	none

get_uma and get_isr_table work offline with no configuration. Their data ships inside the package; each table cites the document it was taken from and the date it was verified.

The bundled UMA covers up to 2026. From 1 February 2027, get_uma returns an error until the package is updated, instead of a stale value.

Get your tokens

Both are free and take a couple of minutes.

1. Banxico: open the SIE API token page, solve the captcha and click "Generar token". The 64-character token appears on the page.
2. INEGI: enter your email in the INEGI token form. The token arrives by email.

You can start with only one token, or none: tools whose token is missing return a message explaining how to get it.

Install

You need uv. The server runs with uvx mcp-mexico; you don't start it yourself, your MCP client does.

Claude Code

claude mcp add mcp-mexico -e BANXICO_TOKEN=your-token -e INEGI_TOKEN=your-token -- uvx mcp-mexico

Claude Desktop

Add this to claude_desktop_config.json (Settings → Developer → Edit Config) and restart Claude Desktop:

{
  "mcpServers": {
    "mcp-mexico": {
      "command": "uvx",
      "args": ["mcp-mexico"],
      "env": {
        "BANXICO_TOKEN": "your-token",
        "INEGI_TOKEN": "your-token"
      }
    }
  }
}

Cursor

Add the same mcpServers block to ~/.cursor/mcp.json.

Try it

Ask your assistant:

• "What is today's FIX exchange rate?"
• "What was annual inflation in Mexico in December 2024?"
• "How much is 30 UMAs in pesos this year?"
• "Using the 2026 monthly ISR table, how much tax is withheld on a 25,000 peso salary?"

Configuration

Variable	Required	Description
BANXICO_TOKEN	For Banxico tools	Banxico SIE API token.
INEGI_TOKEN	For INEGI tools	INEGI Indicators API token.

Responses are cached in memory only: up to 1 hour for latest values, 24 hours for past Banxico ranges and 6 hours for the INPC series. Nothing is written to disk.

Development

uv sync
uv run pytest
uv run ruff check . && uv run ruff format --check . && uv run mypy .
uv run mcp-mexico      # starts the server over stdio

Tests never touch the network: they replay responses recorded from the real APIs. See CONTRIBUTING.md.

Disclaimer

This project is not affiliated with Banco de México, INEGI or the SAT. Figures come from their public sources, but check the cited source before relying on them for tax or legal decisions.

License

MIT © Diego Tepichin