US Tax Estimator

com.yz-cpaPublished by yz-cpa.comOfficial publisherv1.3.0Updated Nov 7, 2026

Federal tax estimate, deadlines, FBAR/8938/3520 checks, §7702 screen, inherited-stock step-up.

VerifiedStreamable HTTPWeb executableFinanceData & Analytics

Overview

AI-generated overview

Remote MCP server with U.S. federal tax calculators: income tax estimates, deadlines, foreign reporting checks and step-up basis.

What you can do
  • Estimate federal income and self-employment tax, refund or balance due, rates, bracket breakdown and safe-harbor payments
  • List upcoming federal tax deadlines, including quarterly estimated payments and entity returns
  • Check foreign-asset figures against FBAR, Form 8938 and Form 3520 thresholds
  • Screen a non-U.S. savings-type life insurance policy against the IRC §7702 definition
  • Compare catch-up options for missed FBAR or Form 8938 filings or unreported foreign income
  • Estimate date-of-death value, §1014 step-up basis and avoided capital-gains tax for inherited securities or crypto
When to use it
Useful when an assistant needs quick, structured U.S. tax figures for planning discussions: rough liability and withholding checks, deadline lookups, foreign reporting threshold questions, or explaining the cost of offshore compliance paths.
Requirements
Remote streamable HTTP endpoint; no account, API key or environment variables declared. The estimate tool supports tax years 2025 and 2026. The step-up tool looks up public market prices, so network access on the server side is implied.
Before you install
Results are simplified estimates, not tax advice, and should be presented as such. The foreign reporting and §7702 tools only apply thresholds and do not decide which accounts or policies qualify. Figures you pass are sent to a third-party service, though it states nothing is stored.

Installation

In SourceWeft

  1. Open US Tax Estimator in the dashboard and add it to a workspace.
  2. Enable the server for the chats that should use its tools.

Web executable via Streamable HTTP. Remote servers run from the web runtime once configured in a workspace.

Use with an agent

Paste this prompt into Claude Code, Codex, Cursor or another agent — or into SourceWeft chat. The agent reads this server's install guide, shows you its publisher, endpoint and sign-in, and adds it to your client once you agree. Keys never go into a command.

Read https://sourceweft.com/mcp/com.yz-cpa%2Fus-tax-estimator/install.md and connect the MCP server it describes to my client. Before changing any config, show me its publisher, endpoint and sign-in method and wait for my OK. Never put an API key in a command or in a file I would commit; ask me where it should come from.

Read the install guide the agent follows

Other MCP clients

Add this to your client's mcpServers config.

{
  "mcpServers": {
    "us-tax-estimator": {
      "type": "http",
      "url": "https://my.yz-cpa.com/mcp"
    }
  }
}

Tools

6

estimate_federal_tax

Estimate federal income and self-employment tax

Estimates a year's U.S. federal income tax plus self-employment tax, the refund or balance due after withholding and estimated payments, marginal and effective rates, a bracket-by-bracket breakdown and, when prior-year figures are given, the safe-harbor quarterly estimated payment. Also answers 'how much more can I earn, withdraw from a 401(k) or convert to a Roth IRA before the next bracket': the room left in the current bracket, the room before qualified dividends / long-term gains lose the 0% rate, and the tax on a planned extra amount. Uses the standard deduction (with the age-65+ addition) unless larger itemized deductions are given; the 2025–2028 $6,000 senior deduction per person 65+ with phase-out (not available when married filing separately); qualified dividends and long-term gains at 0%/15%/20%; child tax credit with phase-out; Social Security wage base and Additional Medicare tax. Federal only: no state tax, AMT, NIIT, QBI deduction, IRMAA or other credits.

Parameterstax_yearrequiredw2_wagestotal_incomerequiredfiling_statusrequiredprior_year_agifederal_withholdingitemized_deductionsqualifying_childrenplanned_extra_incomeprior_year_total_taxself_employment_profitestimated_payments_made+2 more

list_federal_tax_deadlines

Upcoming federal tax deadlines

Lists upcoming U.S. federal tax deadlines with days remaining: quarterly estimated payments (1040-ES), individual return and extension dates, and optionally S-corporation, partnership and C-corporation return and estimated-tax dates. Dates are already moved off weekends and holidays.

Parameterslimitfrom_dateinclude_business

check_foreign_reporting_requirements

Check FBAR, Form 8938 and Form 3520 thresholds

Checks a U.S. person's foreign-asset figures against the filing thresholds for FBAR (FinCEN Form 114), Form 8938 (FATCA) and Form 3520 (gifts or bequests from a foreign individual or estate). Only the forms whose figures are given are checked. Thresholds only: it does not decide which accounts or assets count; the descriptions of each input say what to include.

Parameterslives_abroadfiling_statusrequiredforeign_gifts_receivedspecified_foreign_assets_maxforeign_accounts_max_aggregatespecified_foreign_assets_year_end

screen_foreign_life_insurance_7702

Screen a non-U.S. life insurance policy under IRC §7702

Preliminary screen of whether a non-U.S. savings-type life insurance policy (for example a Hong Kong whole-life or savings plan) meets the U.S. definition of life insurance under IRC §7702, using the cash value accumulation test (CVAT) and the cash value corridor, from the policy's cash value table. A policy that fails is taxed each year on its inside growth (§7702(g)). Values in any one currency (ratios do not depend on currency). Does not check the guideline premium limit.

Parameterssexrequiredissue_agerequiredissue_yearrequiredpolicy_yearsrequiredincreasing_benefit_rule

compare_offshore_compliance_options

Compare catch-up options for unreported foreign assets

For a U.S. taxpayer who missed FBAR or Form 8938 filings or left foreign income unreported, estimates and compares the cost of three catch-up paths: A) delinquent information return procedures (only when no income went unreported), B) amended returns with tax and interest plus a reasonable-cause statement (with the statutory penalty exposure if reasonable cause is rejected), and C) the Streamlined Domestic Offshore Procedures (tax, interest and the 5% penalty). Also adds the 1% Form 720 excise tax on premiums paid to foreign insurers. Tax years 2019–2025. Assumes non-willful conduct; it does not decide eligibility.

Parametersyearsrequiredfiling_statusrequired

estimate_inheritance_step_up

Estimate the basis step-up on inherited stocks and funds

For U.S.-listed stocks, ETFs, mutual funds or crypto held at someone's death (directly, in an estate or in a revocable living trust), estimates the value on the date of death from public market prices, the IRC §1014 step-up in cost basis and the capital-gains tax the heirs avoid (15%–23.8%), plus the dates that matter: the §2032 alternate valuation date, the Form 706 due date and the last day for a portability election (Rev. Proc. 2022-32). Valuation follows Treas. Reg. §20.2031-2(b) (mean of high and low, weekend and no-trade days weighted) and §20.2031-8(b) for funds. Up to 25 holdings. An estimate for planning, not a signed valuation a broker or the IRS will accept; the reply says where to get one.

Parametersholdingsrequireddate_of_deathrequired

Version history

3
  1. v1.3.0LatestNov 7, 2026
  2. v1.1.0Oct 19, 2026
  3. v1.0.1Oct 18, 2026

Score

83% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

  • Reached in the last 30 daysRequired25 pts
  • Auth declaredRequired10 pts
  • Tools listedRequired15 pts
  • DescriptionRequired15 pts
  • Logo10 pts
  • Documentation15 pts

    Declare a GitHub repository with a README, or serve resource_documentation in the OAuth protected-resource metadata.

  • LicenseNot applicable

    A hosted service is used under its provider's terms, so no license is expected here. This check is left out of the percentage.