Which assistants does this work with?

Any MCP-capable assistant, because PiggySize is a standard MCP server with no client allowlist. Claude and Claude Code connect from their connector settings. ChatGPT works too — you turn on Developer mode first, and its Deep Research feature expects its own search and fetch tools, so PiggySize’s finance tools may not surface there. Cursor, VS Code with GitHub Copilot, Windsurf and others connect the same way. The list grows as more assistants adopt the protocol.

What can my assistant actually see?

Only what a tool returns, and only when it calls one. That is your bills, income, assets, debts, goals, businesses, saved scenarios, saved net-worth snapshots and a short profile — filtered by the same family permissions you have in the app. Account numbers, employer identification numbers, email addresses and birthdays are never part of a result.

Can it change my records?

Only if you granted read & write at the consent screen. With read-only, every write tool refuses and tells the assistant to ask you to reconnect. Even with write access, the tools add, edit and delete records in PiggySize — nothing anywhere can move, send or pay money, because PiggySize has no connection to any bank or card.

Yes, at any time, from Settings → Connections in PiggySize. Revoking takes effect on the connector’s very next request. You can also disconnect from the assistant’s side, and an access key stops working an hour after it was issued unless it is renewed.

Does PiggySize store my conversations?

No. Your conversation lives with your assistant, not with us — we never receive it. What we keep is a line per tool call: which tool ran, for which account, whether it succeeded, an error code if it did not, and how long it took. Never the arguments, and never the values that came back.

What about my kids’ accounts?

A child connecting their own account sees only their own scope, the same way they do in the app: their assigned bills, income, assets and debts. Businesses and saved net-worth snapshots come back empty for a child, and saved scenarios are readable only by the family owner or spouse.

Which PiggySize plans is it available on?

Every plan, including Free, while the connector is in preview. The one exception is the businesses tool, which needs a plan that includes business tracking — the same gate the app applies. What you can do on the assistant’s side may depend on that assistant’s own plan (custom connectors, for example, need a paid tier in some apps).

It will not connect — what should I check?

Make sure the address is exactly https://piggysize.com/api/mcp with no trailing slash, and that you finished the PiggySize sign-in and pressed Approve rather than closing the tab. If you have two-factor authentication switched on, you will be asked for a code before the connection is created. If it connected but every tool now fails, check Settings → Connections — the connection may have been revoked, or the hourly limit reached.

Ask your AI assistant about your money.

PiggySize is a standard MCP server, so any MCP-capable assistant — Claude, ChatGPT and others — can connect and the answers stop being generic. It works from your bills, your income, your debts and your goals — the numbers you already keep here.

How to connect Create a free account

You approve the connection in your browser. Read-only is one of the two choices, and you can revoke it whenever you like.

What it is

A chat that already knows your numbers

PiggySize publishes a connector — a small set of tools your assistant can call while you talk to it. When a question needs a figure, the assistant fetches it from your account instead of guessing, then answers in the conversation you were already having. You never paste a spreadsheet, and you never re-type a balance.

Things people actually ask

“What does my month look like — what is coming in, what is going out?”
“Which of my bills are essential, and what is left over after them?”
“Rank my debts by interest rate and show what each one is costing me.”
“How are my goals tracking, and which one is behind?”
“Compare my net worth now with the snapshot I saved in January.”
“Add my new $18 streaming bill, due on the 4th.”

The last one only works if you granted write access. Every other example is a read.

Setup

Connecting takes about a minute

The server address

This is the only thing you paste into any assistant. There are two: the main one, where you choose the access level yourself, and a read-only one that cannot offer write access at all.

Read & write

You still pick read-only or read & write when you approve it.

https://piggysize.com/api/mcp

Read-only

Serves the 13 read tools and nothing else. The choice is made for you.

https://piggysize.com/api/mcp/readonly

The generic way — works with any MCP client

PiggySize is a standard MCP server (OAuth 2.1 over streamable HTTP), so the setup is the same everywhere. Wherever your assistant keeps its connector or MCP settings:

Add a custom or remote MCP connector
Point it at the server address above. A read-only setup uses the read-only address instead.
Sign in to PiggySize when it opens
A PiggySize page opens in your browser. If you have two-factor authentication on, you will be asked for a code first.
Choose the access level and approve
Read-only lets the assistant look at your data. Read & write also lets it add, edit and delete bills, income, assets and debts. Deny is right there too.

The clients below are examples of where each one hides that flow — the list grows as more assistants adopt the protocol.

Claude

On the web, desktop or mobile: Settings → Connectors → Add custom connector, paste the address, choose Connect, sign in to PiggySize, then pick Read-only or Read & write and Approve. In the terminal, use Claude Code (below). What you can add and how much you can use it depends on your Claude plan.

ChatGPT

Turn on Developer mode(Settings → Apps → Advanced) — available on the web app for Plus, Pro, Business, Enterprise and Edu plans — then add a custom connector, paste the address and complete the OAuth sign-in. One honest caveat: ChatGPT’s Deep Research expects a connector’s own search and fetchtools, so PiggySize’s finance tools may not surface in every ChatGPT feature.

Cursor

Open Settings → Tools & MCP → Add custom MCP (or add the server under mcpServers in .cursor/mcp.json with a url), then finish the browser sign-in Cursor opens.

VS Code (GitHub Copilot)

Add an HTTP server to mcp.json — { "type": "http", "url": "…" } — then click the Auth action above the entry to complete the sign-in.

Claude Code

Two commands. The first registers the server, the second opens the same browser approval as everywhere else.

claude mcp add --transport http piggysize https://piggysize.com/api/mcp

claude mcp login piggysize

For a read-only setup, swap the address for https://piggysize.com/api/mcp/readonly.

Any other MCP client

Windsurf, and anything else that speaks the Model Context Protocol over streamable HTTP and signs in with OAuth, connects the same way — add the server address in its MCP settings and complete the browser sign-in. There is nothing client-specific about the server.

Access levels

You decide how far it reaches

The approval screen offers exactly two choices, and it says which app is asking. A connection can never quietly upgrade itself later — moving from one to the other means approving again.

Read-only

View your profile and financial data. It cannot change anything. 13 tools, all of them lookups.

Read & write

Everything above, plus adding, editing and deleting bills, income, assets, debts and goals, and adding or editing businesses. Records only — see the note below.

“Write” means a row in PiggySize. Nothing else.

Deleting a bill here deletes the record you keep; it does not cancel anything with the biller. Deleting an asset does not close an account, and deleting a debt does not settle it. PiggySize has no link to any bank or card — everything in it got there because someone typed it — so there is no path by which a connector could move money even if it were asked to.

The tools

Everything the connector can do, listed

31 tools — 13 read and 18 write. Nothing is hidden: this is the whole surface, and a read-only connection is offered only the 13 read tools.

Read — available on every connection

The 13 read tools, with what each one returns
Tool	What it does
Financial overview`piggysize_get_overview`	Net worth, total assets and total liabilities, plus monthly gross income, essential bills, discretionary bills and discretionary income, with a record count per category.
Monthly cash flow`piggysize_get_cash_flow`	Monthly take-home income, essential and discretionary bills, and what is left over — plus the bills falling due in the next 1–90 days.
List bills`piggysize_list_bills`	Recurring bills with the amount, how often each is due, its category, and whether it is marked essential. Reads records only — it does not pay anything.
List income sources`piggysize_list_income`	Income sources with pay rate, pay frequency, tax rate and the family member or business each belongs to.
List assets`piggysize_list_assets`	Accounts, property and investments with current value, category, institution and owners. Account numbers are not included.
List debts`piggysize_list_debts`	Debts and liabilities with outstanding balance, interest rate, maturity and owners. Account numbers are not included.
List savings and payoff goals`piggysize_list_goals`	Goals with target amount and date, amount saved so far, progress, and an assessment of whether each is on track.
List businesses`piggysize_list_businesses`	Businesses with entity type, industry, estimated tax rate and valuation settings. Employer identification numbers are never returned. Needs a plan that includes businesses.
List business expenses`piggysize_list_business_expenses`	One business’s expenses — the bills allocated to it — with the full bill amount, the percentage allocated, and the business’s own share. Needs a plan that includes businesses.
Business financial summary`piggysize_get_business_summary`	One business’s annual revenue, expenses and profit, the assets and debts on its own books, and its valuation under the method you chose. Needs a plan that includes businesses.
List what-if scenarios`piggysize_list_scenarios`	Saved what-if scenarios — named sets of income and bill changes — with how many additions and removals each holds. Owner or spouse only.
Net worth history`piggysize_get_net_worth_history`	The dashboard snapshots you saved, newest first: a dated record of net worth, assets, liabilities and the monthly figures at the time. It does not reconstruct history you never saved.
Account profile`piggysize_get_profile`	Who the connection is acting as — display name, role in the family, family name, timezone, and family members by name and relationship. Email addresses and birthdays are never included.

Write — only if you approved read & write

The 18 write tools, with what each one changes
Tool	What it does
Add a bill`piggysize_create_bill`	Records a new recurring bill so it counts toward the budget. This creates a record — PiggySize does not move money and cannot pay a bill.
Update a bill`piggysize_update_bill`	Changes fields on an existing bill record. Only the fields provided change; everything else is left alone.
Delete a bill`piggysize_delete_bill`	Permanently deletes a bill record and its links to assets and businesses. It does not cancel anything with the biller.
Add an income source`piggysize_create_income`	Records a new income source so it counts toward budget and take-home figures. Supplemental pay — bonuses, tips, per diem, 401(k) match — must still be added in the app.
Update an income source`piggysize_update_income`	Changes fields on an existing income record. Supplemental pay and payroll deductions are not editable through the connector.
Delete an income source`piggysize_delete_income`	Permanently deletes an income record along with its payroll deductions.
Add an asset`piggysize_create_asset`	Records a new account, property, vehicle or investment so it counts toward net worth. It does not open or fund anything.
Update an asset`piggysize_update_asset`	Changes fields on an existing asset record, such as its current value. This edits a record and does not move money.
Delete an asset`piggysize_delete_asset`	Permanently deletes an asset record. It does not close any real account.
Add a debt`piggysize_create_debt`	Records a new debt or liability so it counts against net worth. It does not borrow, pay down, or transfer anything.
Update a debt`piggysize_update_debt`	Changes fields on an existing debt record, such as its outstanding balance. This edits a record and does not move money.
Delete a debt`piggysize_delete_debt`	Permanently deletes a debt record. It does not settle or close the real obligation.
Add a goal`piggysize_create_goal`	Records a new savings or debt-payoff goal, optionally linked to a real account or debt so progress tracks that balance automatically.
Update a goal`piggysize_update_goal`	Changes fields on an existing goal record, such as the target amount, the target date or which account it tracks. Only the fields provided change.
Delete a goal`piggysize_delete_goal`	Permanently deletes a goal record and the contributions logged against it. The account or debt it tracked is not deleted and its balance is unchanged.
Log a goal contribution`piggysize_log_goal_contribution`	Records a contribution against a goal and returns its recalculated progress. Contributions are append-only — a mistake is corrected by logging the negative.
Add a business`piggysize_create_business`	Records a new business, along with the equity asset that carries its valuation into net worth and the owners’ pass-through income. EINs cannot be set through a connector. Needs a plan that includes businesses.
Update a business`piggysize_update_business`	Changes fields on an existing business record. Renaming it or changing its entity type or valuation settings rewrites the derived income and equity figures. EINs cannot be set through a connector.

Security and privacy

Handing an assistant your finances deserves some detail

You add the connector

In your assistant, you paste the PiggySize server address once. It sends you to us to sign in.

You approve it here

On a PiggySize page, signed in as you, you pick read-only or read & write — and you can say no.

The assistant gets a limited key

It only covers what you approved. It expires every hour and renews itself until you revoke it.

Every request is re-checked

Your family permissions are applied on each call, so the connector can never reach further than you can.

We never keep a copy of the answer

Our log records that a tool ran, which one, whether it worked and how long it took. Not what it returned, not what you asked, not a single figure from it.

You can watch it and end it

Settings → Connections lists every connection, what it may do and when it was last used. Revoke takes effect on the very next request.

How an assistant’s connection to PiggySize is set up, and what it is allowed to do afterwards.

The same permissions you already have

Every tool call is checked against the family permission system the app itself uses. A child account reaches only the records assigned to it, exactly as in the app — and being a PiggySize staff member grants a connector nothing extra.

Some things simply never leave

Account numbers, employer identification numbers, email addresses and birthdays are not part of any tool result. The tools return a fixed list of fields, so a value that is not on that list cannot slip out.

A read-only connection, if you want one

You pick the access level at the consent screen, and there is a separate read-only server address for a connection that should never have been offered the choice.

Hourly limits on the account

A connection can make 300 read calls and 60 write calls an hour. The limits are counted per PiggySize account, so adding more connections does not buy more.

Revoking works immediately

Settings → Connections lists every connection with what it may do and when it last ran, and Revoke takes effect on the very next request rather than whenever a token would have expired.

We log that it ran, not what it said

Our record of a tool call is the tool name, whether it succeeded, an error code and how long it took. Not the question, not the answer, not one figure from it.

If something goes wrong, it can be switched off

You can revoke any connection from Settings → Connections. On our side, an administrator can switch the connector off for a single account, or turn the whole thing off for everyone — the connector is behind a kill switch, and it starts in the off position.

Manage your connections How we handle data everywhere else

Questions people ask

Which assistants does this work with?: Any MCP-capable assistant, because PiggySize is a standard MCP server with no client allowlist. Claude and Claude Code connect from their connector settings. ChatGPT works too — you turn on Developer mode first, and its Deep Research feature expects its own search and fetch tools, so PiggySize’s finance tools may not surface there. Cursor, VS Code with GitHub Copilot, Windsurf and others connect the same way. The list grows as more assistants adopt the protocol.
What can my assistant actually see?: Only what a tool returns, and only when it calls one. That is your bills, income, assets, debts, goals, businesses, saved scenarios, saved net-worth snapshots and a short profile — filtered by the same family permissions you have in the app. Account numbers, employer identification numbers, email addresses and birthdays are never part of a result.
Can it change my records?: Only if you granted read & write at the consent screen. With read-only, every write tool refuses and tells the assistant to ask you to reconnect. Even with write access, the tools add, edit and delete records in PiggySize — nothing anywhere can move, send or pay money, because PiggySize has no connection to any bank or card.
Can I revoke it?: Yes, at any time, from Settings → Connections in PiggySize. Revoking takes effect on the connector’s very next request. You can also disconnect from the assistant’s side, and an access key stops working an hour after it was issued unless it is renewed.
Does PiggySize store my conversations?: No. Your conversation lives with your assistant, not with us — we never receive it. What we keep is a line per tool call: which tool ran, for which account, whether it succeeded, an error code if it did not, and how long it took. Never the arguments, and never the values that came back.
What about my kids’ accounts?: A child connecting their own account sees only their own scope, the same way they do in the app: their assigned bills, income, assets and debts. Businesses and saved net-worth snapshots come back empty for a child, and saved scenarios are readable only by the family owner or spouse.
Which PiggySize plans is it available on?: Every plan, including Free, while the connector is in preview. The one exception is the businesses tool, which needs a plan that includes business tracking — the same gate the app applies. What you can do on the assistant’s side may depend on that assistant’s own plan (custom connectors, for example, need a paid tier in some apps).
It will not connect — what should I check?: Make sure the address is exactly https://piggysize.com/api/mcp with no trailing slash, and that you finished the PiggySize sign-in and pressed Approve rather than closing the tab. If you have two-factor authentication switched on, you will be asked for a code before the connection is created. If it connected but every tool now fails, check Settings → Connections — the connection may have been revoked, or the hourly limit reached.

Your assistant works from the figures in your account and can be wrong about what they mean. Anything it says is information, not financial, tax or investment advice — PiggySize is a tracking and planning tool, and neither it nor an assistant reading it is a substitute for a qualified professional.

Give your assistant something real to work with

Track your bills, income, assets and debts in PiggySize, then connect it once and ask whatever you like. The connector is available on every plan while it is in preview.

Get started free

No card to start. Already have an account? Connect it from Settings → Connections.