Model Context Protocol

Query official data straight from your AI chat

Query official Brazilian data — CPF, CNPJ, vehicles, compliance, credit and more — in natural language through Claude, ChatGPT, Cursor or any MCP-compatible agent. 107+ queries available, and every execution shows the cost in BRL and requires explicit confirmation before spending balance. No billing surprises.

MCP server endpoint
https://app.fontedata.com/mcp
OAuth 2.1 Streamable HTTP No API key

How it works

Three tools, one transparent flow. The AI discovers the catalog on its own — and nothing is charged without your confirmation.

01 free
listar_consultas

Discover

The AI searches the catalog by free text or category and sees each query's name, description, base price and parameters.

02 free
descrever_consulta

Inspect

For a specific query, it returns the parameters (name, type, required or not), your account's price and a sample response.

03 free
executar_consulta

Confirm

The first call spends nothing: it returns the exact cost and a single-use confirmation token.

No query is ever charged without an explicit confirmation with the cost on the table.

In practice

A conversation with the FonteData connector enabled:

Claude

Is CNPJ 67.011.070/0001-16 active with the Federal Revenue?

tool call executar_consulta(slug: "consulta-cnpj-receita", parametros: {cnpj: "67011070000116"}) → confirmation_required · R$ 0.16

I found the Federal Revenue CNPJ query. It costs R$ 0.16 and will be debited from your FonteData balance. Shall I run it?

Go ahead.

tool call executar_consulta(…, confirmar: true, confirmation_token: "eyJh…") → status: ok

FONTEDATA TECNOLOGIA LTDA — registration status ACTIVE, legal nature 206-2 (Limited Liability Company). Charged R$ 0.16.

Simulated interfaces for illustration purposes. Claude and ChatGPT are trademarks of their respective owners.

Security and spending control

Connecting an AI to your balance takes more than an API key pasted into a chat. That's why we use no API key at all.

OAuth 2.1 end to end

Mandatory PKCE S256, Dynamic Client Registration (RFC 7591) and automatic discovery (RFC 8414/9728). Login happens in the browser, on the FonteData portal, with a consent screen — your password and keys never go through the chat.

Two-phase confirmation

Every execution requires a confirmation token issued together with the exact cost. The AI cannot spend "in the dark" — and retries are idempotent, with no double charges.

Minimal scopes, annotated tools

Listing and describing (consultas:read) is free and read-only; executing (consultas:execute) is a separate permission you approve at consent time. The tools carry the MCP spec's safety annotations — the client knows what is read-only and what spends balance.

Short-lived tokens, protected balance

30-minute access tokens and refresh tokens with automatic rotation. Without sufficient balance, nothing runs — the response only carries a secure top-up link.

Connect it to your favorite chat

All you need is the server URL — registration and login happen automatically, in the browser. Pick your client:

  1. On claude.ai (or the Claude Desktop app), open Settings → Connectors.
  2. Click Add custom connector.
  3. Name: FonteData · URL: https://app.fontedata.com/mcp — then confirm with Add.
  4. Click Connect: the browser opens the FonteData login. Sign in and authorize the permissions.
  5. In a new chat, enable the connector in the tools menu and ask: "Which CNPJ queries does FonteData offer?"

Available on Free (1 connector), Pro, Max, Team and Enterprise plans. On Team/Enterprise, the organization admin adds the connector.

Same balance, same price

Every query via MCP costs exactly the same as via the REST API — from R$ 0.01 to R$ 21.04, across 107 available queries. Listing and describing queries is free; you only pay when you execute.

A few examples:
CNPJ RF Simples R$ 0.16Validação Cadastral - Brasil R$ 0.54Consulta Veicular R$ 1.99

New accounts get R$ 50 in credits* — no credit card required.

See the full price list →

*Welcome credits available for corporate email accounts, as per the Terms of Service.

Frequently asked questions

Ready to query by conversation?

Create your account, connect the MCP server to your favorite chat and run your first query in minutes. R$ 50 in credits* to get started.

Questions about MCP? Talk to us on WhatsApp

*Welcome credits available for corporate email accounts, as per the Terms of Service.