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Evidence for your next connection.

Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Payments & trading

TapTax

UK tax: take-home pay, self-employed and company tax, VAT, stamp duty, invoices and MTD.

Checks passed
14 / 22

0 failed · 8 not measured

Median response
748 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
49

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Outdated check

Last connection measurement is over 24 hours old. Current availability is unknown.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
402

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 748 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name taptax.

  • Pass
    Lists tools

    tools/list returned 49 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 748 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 748 ms over 1 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    1 of 1 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Not measured
    Stable tool list

    Fewer than two successful probes in 30 days, so tool-list stability is not measured.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Pass
    Parameters documented

    185 of 231 parameters have a description (80%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Pass
    Website matches publisher

    The website host matches the reverse-domain namespace.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-10-10T11:18:42.204413Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using TapTax

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http taptax https://api.taptax.co.uk/mcp

Capabilities

Tools 49

add_transaction

Record a business income or expense in the signed-in person's TapTax, such as a receipt or a payment. The category is the HMRC self-employment box it belongs in. The same entry added twice within 10 minutes is recorded once.

Discovered
calculate_capital_gains_tax

Calculate UK Capital Gains Tax on selling an asset (residential property, shares, a business qualifying for Business Asset Disposal Relief, or other assets) for a tax year: the gain after costs, losses and the annual exempt amount, tax at each rate given other income, and the payment deadline.

Discovered
calculate_child_benefit_charge

Calculate the High Income Child Benefit Charge on an adjusted net income and the Child Benefit received in a tax year: the charge, the benefit kept, and the income the charge starts from.

Discovered
calculate_cis_deduction

Calculate the Construction Industry Scheme deduction on a payment (labour only, materials excluded) at the registered, unregistered or gross-payment rate, the amount received, and whether the year's deductions are likely to be more or less than the tax actually due.

Discovered
calculate_contractor_day_rate

Turn a contractor day rate into annual and monthly income, an hourly equivalent, and take-home pay as a sole trader, through a company outside IR35 and inside IR35, with the best route and the PAYE salary that would take home as much, for a tax year.

Discovered
calculate_corporation_tax

Calculate UK corporation tax on a company's taxable profit for a tax year, including marginal relief between the small profits and main rates, with profit after tax and the effective rate.

Discovered
calculate_dividend_tax

Calculate UK tax on dividends for a tax year, given the dividends and other income: the dividend allowance, tax at the basic, higher and additional dividend rates, and the effective rate.

Discovered
calculate_gross_salary_for_take_home

Work out the gross UK salary needed to take home a given amount a year after income tax, employee National Insurance, student loan and a pension percentage, for a tax year (net to gross).

Discovered
calculate_invoice_due_date

Calculate the date an invoice is due from its date and the payment terms (on receipt, a number of days, end of month, days after month end, a day of the following month, or the statutory 30-day default), with the weekday and whether the terms exceed the statutory limit.

Discovered
calculate_late_payment_interest

Calculate the statutory interest (Bank of England base rate plus 8%) and fixed compensation a business can claim on a late-paid commercial invoice under the Late Payment of Commercial Debts Act, from the amount, the due date and the payment date.

Discovered
calculate_markup

Calculate the selling price, profit and the equivalent profit margin from a cost and a markup percentage.

Discovered
calculate_mileage_allowance

Calculate the tax-free business mileage allowance for a year at HMRC's approved mileage rates for a car or van, motorcycle or bicycle, including the passenger rate, and the tax it saves at the basic or higher rate.

Discovered
calculate_pension_tax_relief

Compare a self-employed person's tax with their current and a higher personal pension contribution in a tax year: the basic-rate relief added to the pension, the reduction in the tax bill, and the net cost of the extra contribution.

Discovered
calculate_pro_rata_salary

Work out a part-time salary from the full-time salary and the hours or days worked compared with full time, with the take-home pay on the pro rata salary for a tax year.

Discovered
calculate_profit_margin

Calculate the profit margin and markup from a cost and a selling price, or the selling price needed for a target margin.

Discovered
calculate_rental_income_tax

Calculate UK income tax on rental profit for a landlord in a tax year, given rent, allowable expenses, mortgage interest (relieved as a 20% tax credit) and other income.

Discovered
calculate_salary_sacrifice

Compare pay before and after a salary sacrifice for a pension or an electric company car: income tax, National Insurance and student loan saved, employer National Insurance saved and passed back, benefit-in-kind tax for a car, the drop in take-home pay, and for a pension the cost per pound added and the saving against paying in from net pay.

Discovered
calculate_savings_interest_tax

Calculate UK tax on savings interest for a tax year, given the interest, any tax already deducted and other income: the starting rate for savings, the Personal Savings Allowance and the tax due.

Discovered
calculate_stamp_duty

Calculate the tax on buying property: Stamp Duty Land Tax in England and Northern Ireland, Land and Buildings Transaction Tax in Scotland or Land Transaction Tax in Wales, by band, with first-time buyer relief, the additional property surcharge and the non-resident surcharge where they apply.

Discovered
calculate_student_loan_repayment

Calculate yearly, monthly and weekly UK student loan repayments on an income for a repayment plan (Plan 1, 2, 4 or the postgraduate loan) in a tax year.

Discovered
calculate_take_home_pay

Calculate take-home pay from a UK salary for a tax year: income tax by band (England, Wales and Northern Ireland, or Scotland), employee National Insurance, student loan repayment and pension contributions, with yearly, monthly and weekly take-home and the employer National Insurance and total cost to the employer.

Discovered
calculate_tax_on_multiple_incomes

Calculate the combined UK tax on income from several sources in one tax year (employment, self-employment, rental profit, dividends and savings interest), allowing for PAYE tax already deducted: income tax, National Insurance, student loan, what is left to pay and take-home.

Discovered
calculate_vat

Add VAT to a net price or take it out of a gross price at the standard (20%), reduced (5%) or any other rate, with the net, VAT and gross amounts.

Discovered
check_mtd_status

Say whether and when Making Tax Digital for Income Tax applies to someone, from their qualifying income: self-employment turnover plus property income, before expenses, as on their Self Assessment return. Employment and pension income do not count.

Discovered
check_tax_code

Check whether a UK PAYE tax code (e.g. 1257L, BR, K475, 1257L W1/M1) looks right for a salary and circumstances, explain what it means, and estimate any over- or under-payment. Flat-rate codes (BR, D0, D1) are only judged when hasMultipleJobs is known; without it the verdict is needs_info. Returns a verdict tier; refund figures are estimates, not amounts owed.

Discovered
check_vat_registration

Check whether a turnover is over the UK VAT registration threshold for a tax year, and compare VAT payable under the standard scheme with the Flat Rate Scheme for the business's sector rate, including the first-year discount, with the cheaper scheme and the difference.

Discovered
check_vat_reverse_charge

Work out whether the domestic VAT reverse charge for construction services applies to an invoice, by HMRC's decision steps. Takes the yes or no answers known so far and returns the next question to answer, or the outcome with what the invoice must say.

Discovered
compare_inside_and_outside_ir35

Compare a contractor's take-home pay working inside IR35 (deemed employment payment, employer National Insurance) with working outside IR35 through a limited company, from the day rate and working days, for a tax year. It compares pay; it does not decide IR35 status.

Discovered
compare_limited_company_and_sole_trader

Compare take-home pay as a sole trader with running the same profit through a limited company (salary plus dividends, corporation tax and accountancy cost) for a tax year, with the annual difference and an approximate break-even profit.

Discovered
compare_salary_and_dividends

For a limited company director, work out take-home pay from a chosen salary plus dividends paid from the remaining profit after employer National Insurance and corporation tax, with every tax and the effective rate, for a tax year.

Discovered
convert_hourly_rate_to_salary

Convert an hourly rate to the annual salary it adds up to for the hours a week and paid weeks a year given, with take-home pay on that salary for a tax year.

Discovered
convert_salary_to_hourly_rate

Convert an annual salary to its gross hourly rate and the take-home pay per hour, for the hours a week and paid weeks a year given, in a tax year.

Discovered
create_invoice

Create and save a draft invoice in the signed-in person's TapTax account from a client name and one or more line items. No saved client, earlier invoice or client email is needed to create it; an email is only needed later, to send it. It is numbered in their sequence, uses their saved business details, and is not sent. Free plans include 3 invoices; paid plans are unlimited.

Discovered
estimate_self_assessment_penalties

Estimate Self Assessment late filing penalties, late payment penalties and late payment interest on the tax due, from how many days late the return was filed and the tax was paid.

Discovered
estimate_self_employed_tax

Estimate UK income tax and Class 4 National Insurance for a sole trader from turnover and allowable expenses, with the take-home figure, effective and marginal rates, payments on account and tailored tips, from HMRC's published rates for the tax year. Works from the figures given, without a TapTax account.

Discovered
generate_invoice_numbers

Generate invoice numbers: the next number after a given one (keeping its prefix and zero padding), or a run of numbers in a chosen format (prefix, separator, optional year or month, number of digits) from a starting number.

Discovered
get_mileage_summary

Read the signed-in person's own mileage log in their TapTax account for a tax year: total miles, the deductible amount at the approved rates, and the most recent trips.

Discovered
get_mtd_deadlines

List the standard Making Tax Digital quarterly update periods and deadlines for a tax year, and which one is next. Updates are cumulative from 6 April.

Discovered
get_tax_position

Read the signed-in person's own TapTax account: their tax year so far, as their dashboard shows it: business income, expenses and profit counted by the filing rule, the estimated income tax and Class 4 NI, how many transactions still need a business-or-personal decision, which quarterly updates they have filed through TapTax, and the next deadline. Needs no figures from the person: everything comes from their records.

Discovered
list_invoices

Read the signed-in person's own invoices from their TapTax account, newest first, with each one's live status (a sent invoice past its due date reads as overdue) and the totals outstanding and overdue. Needs no details from the person.

Discovered
list_transactions

Read and search the signed-in person's own income and expense records in their TapTax account, newest first. Filter by tax year or dates, type, text in the description, or needsReview=true for the ones still waiting for a business-or-personal decision (the review queue). Needs no details from the person beyond what to look for.

Discovered
log_mileage_trip

Record a business journey in the signed-in person's mileage log. TapTax prices it at the approved mileage rate for the tax year (tiered after 10,000 car miles). Commuting to a permanent workplace is not business mileage. Mileage tracking is on the Pro plan.

Discovered
mark_invoice_paid

Record that the client has paid an invoice (dated today). Stops any payment reminders.

Discovered
plan_quarterly_tax_set_aside

Plan how much to set aside for tax as a sole trader under Making Tax Digital, from the year's profit or each quarter's profit: the income tax, Class 4 National Insurance and student loan due, monthly and weekly amounts to put away, running totals by quarter with each update deadline, and any first payment on account.

Discovered
prepare_business_document

Prepare an invoice, quote, receipt, credit note or pro forma invoice in TapTax's free document generator, without a TapTax account. Returns the totals and a link that opens the generator with the document filled in, where the person checks it, adds a logo if they like, and downloads the PDF. The details travel in the link itself and are not stored by TapTax.

Discovered
prepare_quarterly_update

Get the signed-in person's Making Tax Digital quarterly update ready: the cumulative income, expenses and profit from 6 April to the end of the quarter, what still needs reviewing, and a card with a button that opens TapTax to check and file it. Filing itself always happens in the TapTax app, never from the chat, so HMRC receives the details of the device the person files from.

Discovered
send_invoice

Get one of the signed-in person’s invoices ready to email, with its PDF, to the client address on it from their business name. It opens a card showing exactly what the client will receive (who it goes to, the lines and the total) with a Send button. Nothing is emailed until the person presses Send on that card.

Discovered
send_invoice_from_card

Emails the invoice shown on a TapTax send card to its client, when the person presses Send on that card. Needs the one-time token the card was given.

Discovered
update_transaction

Change a transaction the signed-in person owns: mark it business or personal (this is how the review queue is cleared), or correct its category, description, amount or date.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected748 ms49