xearno.tools

Point your agent here

Language models reason well and compute badly. Xearno Tools gives any agent a bench of deterministic, tested calculators for money and business decisions — call a tool instead of doing the arithmetic in-context, and get back both the values and the benchmark read to relay to your user. No key, no signup, CORS open.

MCP

Streamable HTTP, stateless. Mount it and every tool below appears as an MCP tool (names are the slugs with underscores).

# Claude Code
claude mcp add --transport http xearno-tools https://xearno.tools/mcp

# any MCP client config
{ "mcpServers": { "xearno-tools": { "type": "http", "url": "https://xearno.tools/mcp" } } }

REST API

One endpoint per tool. GET returns the JSON schema; POST computes.

GET  https://xearno.tools/api/v1/tools            # list all tools
GET  https://xearno.tools/api/v1/tools/{slug}     # schema + docs for one tool
POST https://xearno.tools/api/v1/tools/{slug}     # compute

# example
curl -s https://xearno.tools/api/v1/tools/runway \
  -H 'content-type: application/json' \
  -d '{"cash": 500000, "burn": 40000}'

Every response has three parts: raw (stable numeric keys — build on these), results (display-formatted), and insights (benchmark reads with a level of good / info / warn / bad).

llms.txt

The whole bench, machine-readable: https://xearno.tools/llms.txt

Guarantees

The bench

Xearno Fortune Tools

  • income_tax — 24 countries in one tool (country parameter); per-country REST endpoints also exist
  • compound_growthWhat a starting amount plus monthly contributions grows into over time.
  • savings_goalThe monthly saving needed to hit a target by a deadline.
  • loan_paymentMonthly payment, total interest, and what paying extra saves.
  • fire_numberThe portfolio that makes work optional, and how far away it is.
  • split_billEven split with tip, rounded so nobody argues.
  • unit_priceWhich package is actually cheaper per unit.
  • percentageWhat is X% of Y, X is what percent of Y, and percent change — all three, correctly.
  • discountSale price after one or two stacked discounts — and why 20% + 10% is not 30% off.
  • tipTip, total, and per-person share — with actual tipping norms by region.
  • salary_to_hourlyConvert between hourly, weekly, monthly, and annual pay at your real hours.
  • overtime_payTime-and-a-half math: weekly gross with overtime, and your blended hourly rate.
  • pay_raiseWhat a raise is worth — and whether it beats inflation at all.
  • simple_interestI = P·r·t — and how far it diverges from compound interest over time.
  • apr_to_apyNominal vs effective rates — what a quoted APR really costs at your compounding frequency.
  • mortgageTrue monthly cost — principal & interest plus taxes, insurance, and PMI, not just the loan.
  • car_loanMonthly car payment with down payment, trade-in, and sales tax — and the long-loan trap.
  • emiLoan EMI, total interest, and the flat-rate trap that makes 10% cost like 18%.
  • sipSystematic Investment Plan returns — with optional annual step-up, honestly assumed.
  • credit_card_payoffHow long your balance really takes to clear — and the minimum-payment trap in numbers.
  • home_affordabilityHow much house you can afford by the 28/36 rule — the underwriting math, honestly applied.
  • currencyConvert between 31 currencies at the official ECB reference rate — and know what your bank adds on top.

Xearno MBA Tools

  • unit_economicsLTV, LTV:CAC, and CAC payback — with the benchmarks that make them mean something.
  • break_evenUnits and revenue needed to cover costs — and how much pricing moves it.
  • runwayHow many months of cash remain, and when to start raising.
  • npv_irrIs this investment worth it — discounted, not vibes.
  • pricing_marginMargin vs markup, and what a discount really costs in volume.
  • market_sizeBottom-up market sizing with a built-in plausibility check.
  • cagrCompound annual growth rate — the honest average that volatile returns hide behind.
  • roiReturn on investment, simple and annualized — comparable numbers instead of raw bragging.
  • vatAdd or remove VAT at any rate — including the divide-not-subtract trap.
  • gstAdd or extract GST — India slabs (5/12/18/28), Australia/NZ/Singapore/Canada rates.
  • freelance_rateThe hourly rate that actually pays your target income — after unbillable time, overhead, and tax.