MCP Tax Tools

12 tools for UK tax calculations and reference lookups — income tax, NI (including category letter rates), VAT, CGT, dividends, corporation tax, student loans, employer costs, tax comparison, and combined take-home pay.

Each tool call costs 10 credits. All tools are read-only and idempotent.

Tool	Description	Parameters
`calculate_income_tax`	Calculate UK income tax for a given gross income and region. Returns a full breakdown by tax band, personal allowance, taxable income, total tax, and effective rate.	gross_income number, required region string tax_year string marriage_allowance_recipient boolean marriage_allowance_transferor boolean blind_persons_allowance boolean
`calculate_national_insurance`	Calculate UK National Insurance contributions. Supports employed (Class 1) and self-employed (Class 2 and Class 4). Returns contribution breakdowns by band.	type string, required annual_salary number annual_profit number tax_year string director boolean
`lookup_ni_categories`	Look up all UK National Insurance category letters (A, B, C, H, J, M, V, Z, plus Freeport and Investment Zone letters) with descriptions and employee/employer contribution rates for a given tax year.	tax_year string
`calculate_take_home_pay`	Calculate UK take-home pay from gross income. Combines income tax, National Insurance, student loan repayments, and pension contributions into a single net pay calculation with full deduction breakdown.	gross_income number, required region string student_loan_plans array pension_contribution_percent number pension_type string tax_year string marriage_allowance_recipient boolean marriage_allowance_transferor boolean blind_persons_allowance boolean
`compare_tax`	Compare take-home pay between two scenarios. Takes two sets of inputs (salary, region, student loans, pension) and returns a side-by-side comparison with differences.	scenario_a object, required scenario_b object, required tax_year string
`calculate_capital_gains_tax`	Calculate UK Capital Gains Tax on a disposal. Accounts for the annual exempt amount. Requires the asset type and the taxpayer's income tax band.	gain number, required asset_type string, required taxpayer_band string, required tax_year string
`calculate_dividend_tax`	Calculate UK dividend tax. Accounts for the dividend allowance. Requires the taxpayer's income tax band to determine the applicable dividend tax rate.	dividend_income number, required taxpayer_band string, required tax_year string
`calculate_corporation_tax`	Calculate UK Corporation Tax on company profits. Handles small profits rate, main rate, and marginal relief for profits between the two thresholds.	profit number, required tax_year string
`calculate_vat`	Calculate UK VAT on an amount. Supports adding VAT to a net amount (exclusive) or extracting VAT from a gross amount (inclusive). Works with standard, reduced, and zero rates.	amount number, required rate_name string, required direction string
`calculate_student_loan`	Calculate UK student loan repayments based on annual income. Supports Plan 1, Plan 2, Plan 4, Plan 5, and Postgraduate loan types. Multiple plans can be calculated simultaneously.	annual_income number, required plan_types array, required tax_year string
`calculate_vat_return`	Calculate the 9 HMRC VAT Return boxes from a set of transactions. Supports standard VAT, flat rate scheme, partial exemption, fuel scale charges, and more. Provide company details, the return period, and an array of transactions.	company object, required period object, required transactions array, required
`calculate_employer_cost`	Calculate the total cost to an employer of hiring staff in the UK. Includes salary, employer National Insurance contributions, and workplace pension. Can calculate for multiple employees.	annual_salary number, required tax_year string pension_rate number num_employees integer employment_allowance boolean

Related Resources

URI	Description
`govdata://tax/years/current`	Current active UK tax year with key dates
`govdata://tax/years`	All available UK tax years
`govdata://tax/income-tax/rates/{tax_year}`	Income tax bands and rates for a given tax year
`govdata://tax/national-insurance/thresholds/{tax_year}`	National Insurance thresholds and rates
`govdata://tax/capital-gains/rates/{tax_year}`	Capital Gains Tax rates and allowances
`govdata://tax/dividends/rates/{tax_year}`	Dividend tax rates and allowances
`govdata://tax/corporation/rates/{tax_year}`	Corporation Tax rates
`govdata://tax/student-loan/thresholds/{tax_year}`	Student loan repayment thresholds
`govdata://tax/pension/allowances/{tax_year}`	Pension annual and lifetime allowances
`govdata://tax/vat/rates`	Current UK VAT rates (standard, reduced, zero)
`govdata://tax/vat/flat-rate-percentages`	VAT flat rate scheme percentages by business type

Related Prompts

Prompt	Description	Arguments
`tax-summary`	Comprehensive summary of all UK tax rates, bands, and thresholds for a given tax year.	tax_year string, optional
`take-home-breakdown`	Payslip-style take-home pay breakdown showing all deductions from gross to net.	gross_income required region optional student_loan_plan optional pension_rate optional
`employer-cost-breakdown`	Total cost of employing someone including employer NI, pension, and statutory costs.	gross_salary required pension_rate optional

View REST API docs for Tax →

Data Coverage

Source	HMRC / GOV.UK
Date range	Income Tax 1990-91–2026-27; National Insurance 1999-00–2026-27; CGT, dividends, Corporation Tax, and VAT 2020-21–2026-27
Records	7 years for CGT, dividends, Corporation Tax, and VAT; 37 years for Income Tax; 28 years for National Insurance
Updated	Annually (after Budget)
Limitations	CGT, dividend, Corporation Tax, and VAT rates before 2020-21 are not available. FRS percentages are a current snapshot, not historically dated.