Artha — Personal Finance & Tax Copilot 🪙

Your money, planned on live data — not guesses. An MCP server (NitroStack TypeScript SDK) that turns any MCP host — Claude, ChatGPT, NitroChat, NitroStudio — into a finance & tax copilot for Indian taxpayers.

Artha (अर्थ) — the Sanskrit word for wealth & prosperity.

The problem

Indians routinely overpay tax (wrong regime, wasted deduction caps) and can't see the real return on their investments — because the tools are either paywalled advisory products or demo apps running on mocked numbers. A straight, trustworthy answer to "what's my tax, what are my real returns, and should I invest or prepay my loan?" is genuinely hard to get.

What it is

Ask in plain English — "I earn ₹30L, have an HDFC fund and a home loan — plan my taxes and should I invest or prepay?" — and Artha orchestrates 16 tools over live, keyless, non-mocked data: real mutual-fund NAVs & XIRR from AMFI, real bank verification from Razorpay, and the actual Finance Act 2025 tax law — returning one coherent, cited answer.

Why it stands out

• 🔴 Real data, provably. Two genuinely live keyless sources (AMFI NAV via MFAPI.in, Razorpay IFSC) + a get_data_freshness tool that timestamps every source on screen. Most demos mock this; Artha doesn't.

• ⚖️ A deterministic advisory council. "Invest or prepay?" is answered by three pure-logic lenses (tax / growth / safety) reconciled by a weighted vote — the multi-agent debate UX with zero extra LLM calls and zero hallucinated numbers (same input → byte-identical output, proven by tests).

• 🧩 All three MCP primitives, done right — 16 tools · 8 resources (incl. a live market snapshot) · 3 prompts — plus rate-limiting, input hardening, a global exception filter, and a node --test suite.

Architecture

src/
├── index.ts                 # bootstrap + process-level crash guards
├── app.module.ts            # @McpApp root — imports every module
├── common/                  # framework-agnostic utilities
│   ├── http.ts              #   keyless fetch (timeout, typed errors)
│   ├── xirr.ts              #   XIRR (Newton–Raphson + bisection) & CAGR
│   ├── validate.ts          #   input coercion (numbers, enums, dates)
│   ├── format.ts            #   ₹ / % formatting
│   ├── disclaimer.ts        #   advice disclaimer
│   ├── exception.filter.ts  #   global @ExceptionFilter
│   └── apikey.guard.ts      #   optional env-gated @Guard
├── data/                    # provided market-news dataset (CSV)
└── modules/
    ├── tax/         # old vs new regime + deduction optimizer (Finance Act 2025)
    ├── funds/       # NAV / returns / XIRR + live scheme universe   (api.mfapi.in)
    ├── bank/        # IFSC / branch verification                    (ifsc.razorpay.com)
    ├── compliance/  # statutory tax due-date calendar
    ├── gains/       # capital-gains estimator (equity vs debt rules)
    ├── rates/       # RBI/FD benchmarks · EMI-vs-invest · data freshness
    ├── news/        # market news & sentiment (dataset-backed)
    ├── council/     # ⚖️ deterministic advisory council
    ├── resources/   # 📚 read-only @Resource endpoints
    └── copilot/     # 🧠 orchestrator (plan_my_finances) + prompts

Each domain module follows the NitroStack pattern: *.data.ts → *.service.ts (@Injectable) → *.tools.ts (@Tool controller) → *.module.ts (wiring, exports its service).

MCP surface

🔧 Tools (16)

📚 Resources (8)

finance://tax/slabs/2025-26 · finance://compliance/calendar · finance://funds/popular (live) · finance://market/snapshot (live Nifty-50 NAVs) · finance://market/events · finance://data-sources · finance://methodology · finance://security

💬 Prompts (3)

finance_copilot · tax_optimization · invest_or_prepay

The agentic demo flow

"I'm 40, ₹30L salary, ₹3L in 80C, HDFC Top 100 fund, home loan at 9% with ₹2L spare — plan everything."

plan_my_finances runs the workflow (streaming progress when called as a task): 🧮 tax → 📈 live fund returns → 🧾 deduction audit → ⚖️ invest-vs-prepay → 📅 deadlines → 🧠 one plan. Every number is derived from a tool call — nothing is fabricated. For the invest-vs-prepay call it convenes the deterministic council (three lenses that can genuinely disagree, then reconcile).

Verified example: ₹18L with ₹2L ELSS → old ₹2,96,400 vs new ₹1,50,800 → new saves ₹1,45,600 (80C auto-capped at ₹1.5L); XIRR/CAGR from live NAV history; council reproducible (byte-identical).

Quick start

npm install          # backend deps
npm run widget install   # widget (Next.js) deps
npm run dev          # start the MCP server (stdio + http)

No API keys required — both external APIs are free and public. Then connect NitroStudio, or embed the NitroChat widget on any page.

npm test             # build + node --test suite

Deployment (NitroStack Cloud)

Deploy the repo, then in the project Environment variables set:

NITROSTACK_APP_MODE=universal

Optional: RBI_REPO_RATE, RATES_ASOF, API_KEY (enables the auth guard). The market-news dataset in src/data/ ships automatically.

Security

Surfaced at runtime via the finance://security resource:

• Auth — optional API-key Guard (off unless API_KEY is set; keyless demo).

• Input validation — Zod + defensive coercion (numbers, enums, dates) in every service.

• Rate limiting — @RateLimit(30/min) on all outbound-API tools and orchestrators.

• Error handling — global ExceptionFilter + process-level guards; no stack traces leak.

• Privacy — no PII persisted, nothing written to disk, HTTPS + timeouts, no secrets.

Data & freshness

Run get_data_freshness to see the live NAV date + fetch timestamp on screen.

Disclaimer

Informational & educational only — not investment, tax, or financial advice. Figures are estimates; verify with a SEBI-registered adviser or a qualified CA before acting. Tax slabs are FY 2025-26 per the Finance Act 2025 (incometax.gov.in).

Links

• NitroStack docs: https://docs.nitrostack.ai

• Demo script: DEMO.md · Community posts: COMMUNITY.md

Built for the NitroStack × Amrita University Coimbatore MCP Hackathon.