The CData MCP Server for TaxJar defines each connection to TaxJar as a named configuration that Claude can use when sending natural language queries.

You create and manage these configurations using the MCP Configuration Tool. The tool automatically handles formatting, storage, and registration with Claude Desktop.

Understanding Connection Configurations

Each connection configuration is stored in a .mcp file. This file includes the details needed to initialize the connector when Claude starts a session.

• On Windows, configuration files are stored in "~/AppData/Roaming/CData/TaxJar Data Provider/".
• On macOS, configuration files are stored in "~/Library/Application Support/CData/TaxJar Data Provider/".

The .mcp file is a text file that contains a list of connection properties and a timestamp. For example:

#Tue May 20 15:48:40 EDT 2025
AuthScheme=Basic
User=myUser
Password=myPassword
Security Token=myToken

The configuration tool handles these settings automatically. Each saved configuration enables Claude to launch a dedicated MCP Server instance with the correct connector and options. Manual file editing is not required.

Authenticating a TaxJar Account

To authenticate to the TaxJar API, you will need to first obtain the API Key from the TaxJar UI. Remember that the API is available only for Professional and Premium TaxJar plans. If you already have a Professional or Premium plan you can find the APIKey by logging in the TaxJar UI and going to Account->TaxJar API. After obtaining the API Key you can set the APIKey connection property. That's all you need to do for a successful connection.

Extra Notes

• By default the server will retrieve data of the last 3 months in case the entity supports date range filtering. You can use the StartDate to set the minimum creation date of the data retrieved.
• If the API Key has been created for a sandbox API account please set UseSandbox to true in order for a successful connection.
• In case you are using a sandbox API account please remember that not everything will work as expected. This is also documented in the TaxJar developer docs here: Sandbox Environment and here: Unsupported endpoints
• The TaxJar API rate limiting is really generous. (10000 requests per minute for TaxJar Professional plans and 25000 per minute for the TaxJar Premium plans).
• Because of the TaxJar API limits we are restricted to make an http request for each row in order to collect as much data as we can. We suggest to increase the value of the MaxThreads connection property.
• The default value of MaxThreads has been set to 20 which means it will make at most 20 concurrent requests. To improve the performance of the server consider increasing this value based on the machines resources.