Connect to our MCP server

T:0 exposes an MCP (Model Context Protocol) server so you can give any MCP-compatible AI client — Claude Desktop, Cursor, Windsurf, or your own agent — direct access to your financial data and T:0 actions.

Before you start

You need a T:0 account
You need an MCP-compatible client installed on your machine.
You need your T:0 API key. Find it under Connections → API Keys in the T:0 dashboard.

How it works

The T:0 MCP server runs as a remote, hosted service. You point your client at the server URL and authenticate with your API key. From that point, your AI client can call T:0 tools — such as querying transactions, checking balances, or listing invoices — just as it would call any other tool.

Add the server to your client

Claude Desktop

Open Claude Desktop → Settings → Developer → Edit Config and add the following block to mcpServers:

  {
    "mcpServers": {
      "t0": {
        "type": "http",
        "url": "https://mcp.scalar.com/mcp/f5272265-5f85-4ec5-b4eb-a44e4f05d957",
        "headers": {
          "Authorization": "Bearer <YOUR_API_KEY>"
        }
      }
    }
  }

Replace YOUR_API_KEY with your key from Connections → API Keys.
Save the file and restart Claude Desktop.

Cursor / Windsurf

Open your editor's MCP settings (.cursor/mcp.json or the equivalent for Windsurf).
Add the same block shown above under mcpServers.
Reload the editor.

Claude CLI

Open a terminal window with claude installed and run the following:

claude mcp add \
  --transport http t0 'https://mcp.scalar.com/mcp/f5272265-5f85-4ec5-b4eb-a44e4f05d957' \
  --header 'Authorization: Bearer <YOUR_API_KEY>'

Replace YOUR_API_KEY with your key from Connections → API Keys.

Verify the connection

Once configured, ask your AI client: "Can you list the five most recent invoices from my t0 account?" If the server is connected, it will call the T:0 tool and return your most recent invoices. If you see a tool-not-found or auth error, double-check your API key and that the config file was saved before the client restarted.

Available tools

List endpoints

Tool	What it does
`list_invoices`	Returns a typed list of invoices
`list_vendor_bills`	Returns a typed list of vendor bills
`list_customers`	Returns a typed list of customers
`list_vendors`	Returns a typed list of vendors
`list_payments`	Returns a typed list of payments
`list_line_items`	Returns a typed list of invoice line items
`list_bill_line_items`	Returns a typed list of bill line items

Single-record fetches

Tool	What it does
`get_one_invoice`	Fetches a single invoice by ID
`get_one_vendor_bill`	Fetches a single vendor bill by ID
`get_one_customer`	Fetches a single customer by ID
`get_one_vendor`	Fetches a single vendor by ID
`get_one_payment`	Fetches a single payment by ID
`get_one_line_item`	Fetches a single invoice line item by ID
`get_one_bill_line_item`	Fetches a single bill line item by ID

Generic & write

Tool	What it does
`discover_the_exposed_record_types`	Lists all record types the server exposes
`get_one_record_of_any_type`	Fetches a single record by type and ID without a typed wrapper

Spec & docs helpers

Tool	What it does
`search-documentation`	Full-text search across T:0 help center docs
`search-openapi-operations`	Searches the T:0 OpenAPI spec for matching operations
`summarize-openapi-specs`	Returns a high-level summary of the T:0 API spec
`execute-request`	Executes a raw API call against a specific operation; requires Scalar operation UUIDs

Get help

Email support@t0.ai if your client isn't connecting, if you need a tool that isn't listed, or if you'd like to use the MCP server in a custom agent.

The Dashboard

Add a connection