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
- — Deterministic: same inputs, same outputs, always.
- — Stable: tool slugs and raw-output keys don’t change; breaking changes get new versions.
- — Documented: formulas and benchmark sources are public on each tool’s Methodology section.
- — Same math everywhere: the UI, the API, and MCP share one compute path.
The bench
Xearno Fortune Tools
- income_tax — 24 countries in one tool (country parameter); per-country REST endpoints also exist
- compound_growth — What a starting amount plus monthly contributions grows into over time.
- savings_goal — The monthly saving needed to hit a target by a deadline.
- loan_payment — Monthly payment, total interest, and what paying extra saves.
- fire_number — The portfolio that makes work optional, and how far away it is.
- split_bill — Even split with tip, rounded so nobody argues.
- unit_price — Which package is actually cheaper per unit.
- percentage — What is X% of Y, X is what percent of Y, and percent change — all three, correctly.
- discount — Sale price after one or two stacked discounts — and why 20% + 10% is not 30% off.
- tip — Tip, total, and per-person share — with actual tipping norms by region.
- salary_to_hourly — Convert between hourly, weekly, monthly, and annual pay at your real hours.
- overtime_pay — Time-and-a-half math: weekly gross with overtime, and your blended hourly rate.
- pay_raise — What a raise is worth — and whether it beats inflation at all.
- simple_interest — I = P·r·t — and how far it diverges from compound interest over time.
- apr_to_apy — Nominal vs effective rates — what a quoted APR really costs at your compounding frequency.
- mortgage — True monthly cost — principal & interest plus taxes, insurance, and PMI, not just the loan.
- car_loan — Monthly car payment with down payment, trade-in, and sales tax — and the long-loan trap.
- emi — Loan EMI, total interest, and the flat-rate trap that makes 10% cost like 18%.
- sip — Systematic Investment Plan returns — with optional annual step-up, honestly assumed.
- credit_card_payoff — How long your balance really takes to clear — and the minimum-payment trap in numbers.
- home_affordability — How much house you can afford by the 28/36 rule — the underwriting math, honestly applied.
- currency — Convert between 31 currencies at the official ECB reference rate — and know what your bank adds on top.
Xearno MBA Tools
- unit_economics — LTV, LTV:CAC, and CAC payback — with the benchmarks that make them mean something.
- break_even — Units and revenue needed to cover costs — and how much pricing moves it.
- runway — How many months of cash remain, and when to start raising.
- npv_irr — Is this investment worth it — discounted, not vibes.
- pricing_margin — Margin vs markup, and what a discount really costs in volume.
- market_size — Bottom-up market sizing with a built-in plausibility check.
- cagr — Compound annual growth rate — the honest average that volatile returns hide behind.
- roi — Return on investment, simple and annualized — comparable numbers instead of raw bragging.
- vat — Add or remove VAT at any rate — including the divide-not-subtract trap.
- gst — Add or extract GST — India slabs (5/12/18/28), Australia/NZ/Singapore/Canada rates.
- freelance_rate — The hourly rate that actually pays your target income — after unbillable time, overhead, and tax.