worthune

Zero-dependency SDK for the Worthune Model API — 27 financial calculation models you can cite, audit, and trust. No API keys. Free with attribution.

Every model has a published spec, an independent second implementation that must agree with the first on 250 fuzzed cases before anything ships, and IRS/SSA constants traced to primary sources. Model changes are never silent: responses pin specVersion, and the changelog is public.

pip install worthune

from worthune import Worthune, verify_record

client = Worthune()

result = client.run("relocation", {
    "currentSalary": 95000, "newSalary": 108000,
    "currentMonthlyExpenses": 4200, "newMonthlyExpenses": 4900,
    "movingCosts": 6000, "currentSavings": 40000,
    "annualReturn": 0.07, "yearsHorizon": 10,
})

result["outputs"]["breakEvenMonths"]  # 16
result["specVersion"]                 # pinned contract version
result["facts"]                       # IRS/SSA constants used, with sources
result["sentinels"]                   # special values, explained
verify_record(result)                 # True — audit fingerprint checks out

API

• client.list_models() — catalog with spec versions
• client.get_contract(model) — machine-readable inputs/domains/sentinels
• client.get_spec(model) — the full published spec (markdown)
• client.run(model, inputs) — run; validation failures return {"ok": False, "errors": [...]} instead of raising
• client.get_eval_dataset(model) — 250 verified input/expected-output pairs, the exact cases Worthune's dual-implementation CI verifies (ground truth for financial AI testing)
• client.get_facts() — the sourced IRS/SSA constants registry
• verify_record(response) — recompute the SHA-256 decision record to prove where numbers came from (byte-exact ECMAScript-compatible canonical JSON)

Retirement, FIRE, rent vs. buy, refinancing, equity comp (RSUs), debt payoff, Social Security timing, 529 plans, estate planning, and more — the full catalog lists all 27.

Fair use: 5,000 runs/month per app (a guideline, not a meter) — the free tier, in writing.

MIT licensed. The models, specs, and verification harness live behind the API at worthune.com.