GovData Docs

MCP (Model Context Protocol)

Connect AI assistants like Claude directly to GovData. Ask questions about UK tax, companies, and bank holidays in natural language.

What is MCP?

The Model Context Protocol (MCP) is an open standard that lets AI assistants call external tools, read data, and use prompt templates. GovData implements an MCP server so AI assistants can query UK Government data natively — no code required.

Instead of writing API calls, you can ask Claude or any MCP-compatible assistant questions like "What's my take-home pay on a 55k salary in Scotland?" or "Look up company number 00000006" and it will call the right GovData tools automatically.

Connection

GovData's MCP server uses Streamable HTTP transport. Point your MCP client at: 

https://mcp.govdata.dev/mcp

Authentication uses the same API key as the REST API, passed as a Bearer token.

Claude Desktop setup

Add the following to your Claude Desktop configuration file (claude_desktop_config.json): 

{
  "mcpServers": {
    "govdata": {
      "url": "https://mcp.govdata.dev/mcp",
      "headers": {
        "Authorization": "Bearer YOUR_API_KEY"
      }
    }
  }
}

Replace YOUR_API_KEY with your API key from the console. Both test and live keys work with MCP.

Available tools

Tools perform calculations and lookups. Each tool call costs 10 credits.

Tool Description Cost
calculate_take_home_pay Full take-home pay: income tax + NI + student loan + pension in one call 10
calculate_income_tax Income tax with band-by-band breakdown for any region 10
calculate_national_insurance Employee or self-employed NI contributions 10
calculate_vat Add or extract VAT at standard, reduced, or zero rate 10
calculate_vat_return Full 9-box VAT return from transactions 10
calculate_capital_gains_tax CGT on disposals with annual exempt amount 10
calculate_dividend_tax Dividend tax with allowance and band-based rates 10
calculate_corporation_tax Corporation tax with marginal relief 10
calculate_student_loan Student loan repayments for Plans 1, 2, 4, 5, and Postgrad 10
lookup_company Look up a UK company by Companies House number 10
search_companies Search UK companies by name with optional status filter 10

Available resources

Resources provide read-only reference data. Each resource read costs 1 credit.

Static resources

URI Description Cost
govdata://tax/years/current Current active UK tax year with key dates 1
govdata://tax/years All available UK tax years 1
govdata://tax/vat/rates Current UK VAT rates (standard, reduced, zero) 1
govdata://tax/vat/flat-rate-percentages VAT flat rate scheme percentages by business type 1
govdata://calendar/bank-holidays/next Next upcoming UK bank holidays by region 1
govdata://companies/sic-codes UK Standard Industrial Classification codes directory 1
govdata://companies/statistics Platform-wide UK company statistics 1

Parameterised resource templates

URI template Description Cost
govdata://tax/income-tax/rates/{tax_year} Income tax bands and rates for a given tax year 1
govdata://tax/national-insurance/thresholds/{tax_year} NI thresholds and rates for a given tax year 1
govdata://tax/capital-gains/rates/{tax_year} Capital Gains Tax rates and allowances 1
govdata://tax/dividends/rates/{tax_year} Dividend tax rates and allowances 1
govdata://tax/corporation/rates/{tax_year} Corporation Tax rates 1
govdata://tax/student-loan/thresholds/{tax_year} Student loan repayment thresholds 1
govdata://tax/pension/allowances/{tax_year} Pension annual and lifetime allowances 1
govdata://calendar/bank-holidays/{year} Bank holidays for a specific calendar year 1

Available prompts

Prompts are pre-built templates that guide the AI to use the right tools and present results clearly. Prompts are free — only the tool calls they trigger cost credits.

Prompt Description
tax-summary Comprehensive summary of all UK tax rates, bands, and thresholds for a tax year
take-home-breakdown Payslip-style take-home pay breakdown with all deductions from gross to net
company-report Structured company overview from Companies House data

Credit costs

MCP uses the same credit system as the REST API:

Tools

10 credits

Calculations and lookups

Resources

1 credit

Reference data reads

Prompts

Free

Only triggered tools cost credits

Getting started