Envelope

Envelope — connector documentation

• MCP endpoint: https://envelope.connectorbay.com/mcp
• REST API: POST https://envelope.connectorbay.com/v1/tools/{tool_name}, described by the OpenAPI 3.1 spec at https://envelope.connectorbay.com/openapi.json
• Transport: Streamable HTTP, stateless, MCP specification 2025-06-18 or later
• Authentication: none required. An optional Authorization: Bearer <key> raises rate limits.
• Health: https://envelope.connectorbay.com/health · Tool schemas: https://envelope.connectorbay.com/tools.json
• Publisher: Unify Dynamics LLC · connectorbay.com/envelope · agent@connectorbay.com

What Envelope is for

"Does my budget balance", "am I following the 50/30/20 rule", "snowball or avalanche for my credit cards", "how big should my emergency fund be", "what's my net worth", "how much should I save each month for a $1,200 holiday fund" — the day-to-day budgeting and debt-payoff questions people work out on a napkin or a spreadsheet before ever talking to a financial advisor. Envelope answers them with real arithmetic over the numbers you give it — no upstream calls, no accounts, no bundled rate tables, nothing stored.

What it does

Zero-based budgeting. Checks a set of monthly category allocations against income: verifies they sum to (or under) income, flags over-allocation and by how much, and reports the unallocated remainder.

The 50/30/20 rule. Compares actual needs/wants/savings spending against the classic 50% needs / 30% wants / 20% savings-or-debt-payoff guideline, reporting each category's target amount, actual amount, and the gap.

Debt snowball and debt avalanche. Two full month-by-month payoff schedules for the same list of debts: snowball orders smallest-balance-first (for quick psychological wins), avalanche orders highest-interest-rate- first (to minimize total interest). Both roll a paid-off debt's minimum payment into the next target along with any extra payment, keeping the total monthly outlay constant — and both report total months to debt-free, total interest paid, and a per-debt breakdown, so the two strategies can be compared directly for the same debts and the same extra payment.

Emergency fund. Target fund size (monthly expenses x months of coverage) and, given a current balance and monthly contribution, the months remaining to reach it.

Net worth. Sums an assets object and a liabilities object into a net worth figure with a breakdown of each side.

Savings rate. Total savings and extra debt payoff as a percentage of income, with the commonly cited 10% and 20% benchmark bands for context.

Sinking fund. The flat monthly amount needed to reach a planned future expense (a car, an annual premium, a holiday budget) by a target month count — no growth assumed, a plain installment split.

Glossary. Plain-language definitions of 14 common terms: zero-based budgeting, the 50/30/20 rule, the envelope system, debt snowball, debt avalanche, emergency fund, sinking fund, debt-to-income ratio, net worth, savings rate, minimum payment, APR, amortization, and sinking-fund-vs-emergency-fund.

What it is not

Not personalized financial advice, and not a substitute for a financial advisor. It has no idea about your job security, other debts or assets you didn't mention, local cost of living, taxes, or family circumstances — every figure is plain arithmetic over exactly the numbers you supplied. The 50/30/20 split and the 3-6-month emergency fund range are common rules of thumb, not personalized targets. The debt snowball/avalanche schedules assume a constant extra payment and constant minimum payments and interest rates every month (no rate changes, no missed or additional payments, no fees) — real credit card and loan terms can be more complex.

Built and maintained by Unify Dynamics LLC. Contact: agent@connectorbay.com.

Tools

Budgeting

zero_based_budget — Checks a set of monthly category allocations against income: verifies they sum to (or under) income, flags over-allocation and by how much, and reports the unallocated remainder. Use for "does my budget balance", "am I over-allocating my paycheck". Args: income, categories.

fifty_thirty_twenty_check — Checks actual needs/wants/savings spending against the 50/30/20 rule (50% needs, 30% wants, 20% savings-or-debt-payoff): reports each category's target amount, actual amount, and how far off it is. Use for "am I following the 50/30/20 rule". Args: income, needs, wants, savings.

Debt payoff

debt_snowball_plan — Orders debts smallest-balance-first and computes a full month-by-month payoff schedule: each paid-off debt's minimum payment rolls into the next target along with extra_payment, keeping the total monthly outlay constant. Reports payoff order, months to debt-free, total interest paid, and a per-debt breakdown. Use for "snowball payoff plan for my 3 credit cards with $200 extra a month". Args: debts, extra_payment.

debt_avalanche_plan — Same computation as debt_snowball_plan but orders debts highest-interest-rate-first, minimizing total interest paid. Its total_interest_paid can be compared directly against debt_snowball_plan's for the same debts and extra_payment — avalanche never pays more total interest. Use for "avalanche vs snowball for my credit cards", "which payoff order saves the most interest". Args: debts, extra_payment.

Savings & goals

emergency_fund_calculator — Target emergency-fund size (monthly_expenses x months_target) and, given a current balance and monthly contribution, the months remaining to reach it. Use for "how big should my emergency fund be", "how long until I have 3 months of expenses saved". Args: monthly_expenses, months_target, current_balance, monthly_contribution.

sinking_fund_planner — Flat monthly amount needed to reach a planned future expense by a target month count (no growth/interest assumed — a plain savings-installment split). Use for "how much should I save each month for a $1,200 holiday fund in 12 months". Args: goal_amount, months, current_saved.

savings_rate_calculator — Computes savings rate as a percentage of income: total_savings_and_debt_payoff / income. Use for "what's my savings rate", "am I saving enough of my paycheck". Args: income, total_savings_and_debt_payoff.

Net worth & reference

net_worth_calculator — Sums assets and liabilities and reports net worth plus a breakdown of each side. Use for "what's my net worth". Args: assets, liabilities.

budget_glossary — Definitions of common budgeting and debt-payoff terms (zero-based budgeting, sinking fund, debt snowball vs. avalanche, emergency fund, debt-to-income ratio, the envelope system, ...). Use for "what's a sinking fund", "snowball vs avalanche, what's the difference". Args: term.

Conventions

• Read-only. Every tool reads public data or computes; nothing is written anywhere and nothing about the user is stored.
• Result envelope. ok: true with data, or ok: false with a structured error (bad_input, not_found, upstream_error). degraded lists optional sources that were unreachable.
• Rate limits. Free tier 60 tool calls/minute and 300/day per user (keyed on the user identifier supplied by the host agent, else client IP); Pro keys raise this. Over-limit calls return HTTP 429 with Retry-After. initialize and tools/list are never counted.

Support

agent@connectorbay.com · connectorbay.com/envelope/support

Envelope — Privacy Policy

Effective 24 September 2026. Unify Dynamics LLC ("we", "us"), Menlo Park, California.

What Envelope is. Envelope is a connector (an MCP server and REST API) that AI assistants and personal agents call on your behalf for personal budgeting and debt-payoff calculations: zero-based budget checks, the 50/30/20 rule, debt snowball and avalanche payoff schedules, an emergency-fund calculator, net worth, savings rate, and a sinking-fund planner. You interact with your assistant; the assistant sends us only the numbers needed for that one calculation.

What we receive. The arguments of each tool call — income figures, category allocations, debt balances, minimum payments and interest rates, account balances, contribution amounts, asset and liability figures — the technical headers needed to serve the request (an IP address or a client identifier supplied by the assistant, and a Pro API key if you have one), and standard server logs.

Everything is computed on our server and nothing is stored. Every calculation is plain arithmetic over the numbers you provide in that single request — there are no upstream data sources or bundled rate tables to look anything up in. No request is forwarded to any third party, and no query — including any income, balance, or debt figure you enter — is logged in request bodies, recorded, or used to train anything.

What we do not receive or store. We do not receive your conversation with the assistant, your name, account numbers, or any other identifying or account information, and we do not build a financial profile from your queries: each calculation is answered independently and nothing carries over between requests. Rate-limit counters (a client identifier and timestamps) are held in memory for at most 24 hours. Hosting-provider access logs, which contain IP addresses and request paths but not request bodies, are retained for up to 30 days for security and abuse prevention.

Sub-processors. None — every tool is computed locally. Hosting: Vercel (United States regions).

Legal bases and your rights. For users in California, the EU/UK and elsewhere, our processing is necessary to provide the service you request through your assistant. Because we store no personal data beyond short-lived logs, requests to access, correct or delete personal data are usually satisfied automatically; you can still contact agent@connectorbay.com and we will respond within 30 days. We do not sell or share personal information and do not use your data to train models.

Children. Envelope is a general-audience service for adults; we knowingly collect no personal data from anyone.

Changes. We will post changes here with a new effective date.

Envelope — Terms of Service

Effective 24 September 2026. These terms govern use of the Envelope connector ("the Service") operated by Unify Dynamics LLC ("we", "us").

1. The Service. Envelope returns personal budgeting and debt-payoff calculations — zero-based budget checks, 50/30/20 rule comparisons, debt snowball and debt avalanche payoff schedules, emergency-fund and sinking-fund planning, net worth, and savings rate — computed entirely from the numbers you provide in each request. It is accessed through an AI assistant or directly over MCP or HTTP.
2. Not financial advice. Envelope's calculations are general educational information — real arithmetic applied to numbers and assumptions you supply — not a recommendation, and not individualized financial, budgeting, or debt advice. Consult a financial advisor for guidance tailored to your specific situation before making a financial decision.
3. Rules of thumb, not personalized targets. The 50/30/20 split and the 3-6-month emergency-fund range are commonly cited guidelines, not calculated for your circumstances. The debt snowball and avalanche schedules assume constant minimum payments, a constant extra payment, and constant interest rates for the whole payoff period; real loan and credit card terms can change.
4. No advice on which debts to pay, or in what order, is a fiduciary recommendation. Comparing snowball and avalanche results is informational; the "right" strategy for you may depend on factors (motivation, cash-flow risk, promotional rates) this Service does not know about.
5. Estimates, not guarantees. Actual payoff timelines and totals will differ from these projections if your real payments, balances, or rates change.
6. Acceptable use. Automated use within the published rate limits is welcome.
7. Availability. The Service is provided "as is" without warranty. We may change, limit or discontinue it at any time.
8. Data. Our Privacy Policy describes what we process. In short: your query is answered on our server and nothing is stored.
9. Pro keys. Optional Pro API keys are issued at our discretion, are personal to the holder and may be revoked for abuse.
10. Liability. To the fullest extent permitted by law, Unify Dynamics LLC is not liable for any financial loss arising from use of or reliance on the Service. Our total liability is limited to US $100.
11. Governing law. California law; venue in San Mateo County, California.
12. Contact. Unify Dynamics LLC · agent@connectorbay.com · https://connectorbay.com/envelope

Envelope support

Email agent@connectorbay.com. We answer within two business days.

• MCP endpoint: https://envelope.connectorbay.com/mcp
• REST API: https://envelope.connectorbay.com/openapi.json
• Live status: https://envelope.connectorbay.com/health

When you report a problem, include the question you asked your agent, roughly when, and which agent you used (for example Claude, ChatGPT or Gemini). Never send us passwords, account numbers or ID numbers. Envelope never asks for them.