Live for MCP clients · Not listed in ChatGPT yet
Compare health plan costs, to the cent, inside ChatGPT.
Tobie Benefits Compare is a free calculator for ChatGPT. Tell it the plan terms from your enrollment materials, and it works out what each plan costs you in a year: premiums, your share of covered in-network care at spending levels you choose, and how an employer HSA contribution changes the picture. Every figure comes with the assumptions behind it.
MCPhttps://plugins.tobie.team/mcp/benefits-compare
At $5,000 of covered care, compare Plan A ($300 a month, $1,000 deductible, 20% coinsurance, $5,000 maximum) with Plan B ($150 a month, $3,000 deductible, 20%, $6,000 maximum, $1,000 employer HSA).
compare_health_plans
Ran on your numbers only
Illustration with the made-up terms from the worked example below. Out-of-network care, non-covered services and balance billing are outside every figure.
What it calculates
Six figures, each from the terms you give it.
The calculator models employer health plans the way enrollment guides describe them: a premium per paycheck, a deductible, coinsurance after it, and an out-of-pocket maximum. You choose the hypothetical spending levels to compare at.
What it does not doAnnual premiums
From your per-paycheck deduction and the number of paychecks it comes out of. Twelve monthly, 24 semi-monthly, 26 biweekly or 52 weekly deductions; you say which.
Your cost-sharing at a spending level you choose
Deductible first, then coinsurance on the rest, up to the out-of-pocket maximum. For example: "what if I have $5,000 of covered in-network care?"
Employer HSA effects
How much of a hypothetical bill the employer's HSA money could cover, and what is left. HSA money is never subtracted from premiums.
Covered in-network ceiling
Annual premiums plus the in-network out-of-pocket maximum: the most the modelled terms can cost you in the year, with a reminder of what it leaves out.
Where two plans cost the same
The spending levels, if any, at which two plans' totals are equal, found exactly rather than by scanning a grid.
Families
Hypothetical charges split across family members, with embedded or aggregate deductibles and per-person and family limits.
How the numbers are worked out
Every figure has a formula you can read.
All amounts are exact to the cent and rounded once per formula. A term you do not give is reported as missing, never treated as zero.
- Annual premium
deduction per paycheck × number of deductions in the plan year- Your cost-sharing at spending S
min(out-of-pocket maximum, deductible portion of S + coinsurance × the rest)- Premiums plus cost-sharing
annual premium + your cost-sharing at S- Covered in-network ceiling
annual premium + out-of-pocket maximum- HSA used
min(employer HSA balance, your cost-sharing at S)- Cash after HSA
premiums + cost-sharing − HSA used
Worked example
Two plans, three spending levels, one table.
Employee-only coverage. Plan A costs more each month and has a lower deductible; Plan B costs less, has a higher deductible, and comes with $1,000 of employer HSA money available from the start.
The terms you give it
| Term | Plan A | Plan B |
|---|---|---|
| Premium | $300 a month | $150 a month |
| Deductible | $1,000 | $3,000 |
| Coinsurance after the deductible | 20% | 20% |
| Out-of-pocket maximum | $5,000 | $6,000 |
| Employer HSA | none | $1,000, from the start |
What the calculator returns
| Covered in-network spending | Plan A | Plan B | Plan B after HSA |
|---|---|---|---|
| $0 | $3,600.00 | $1,800.00 | $1,800.00 |
| $5,000 | $5,400.00 | $5,200.00 | $4,200.00 |
| $15,000 | $7,400.00 | $7,200.00 | $6,200.00 |
| Covered in-network ceiling | $8,600.00 | $7,800.00 | $7,800.00 |
Plan A and Plan B: premiums plus your share. At $0 of spending Plan B still has its full $1,000 of HSA money left. For these two plans there is no spending level where they cost the same: Plan B's total is lower at every level.
Where two plans cross
Compare Plan A with a Plan C at $200 a month, a $3,000 deductible, 20% coinsurance and a $6,000 maximum, and the calculator finds two crossing points: at exactly $2,500.00 and $20,000.00 of covered spending. Below the first and above the second, Plan C is cheaper; between them, Plan A is. The figures are found exactly, not by scanning a grid.
These are hypothetical figures from made-up terms, for illustration. They are not a forecast and not a recommendation.
How to use it
How to compare two health plans with ChatGPT
Three steps, two minutes, no account. ChatGPT turns your plain-words description into the tool's numeric inputs and shows the figures with their assumptions.
You will need: each plan's premium per paycheck and the number of paychecks; its deductible, coinsurance and out-of-pocket maximum; any employer HSA contribution; one or more hypothetical spending levels.
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01
Gather each plan's terms
From your enrollment guide or benefits portal: the premium per paycheck and how many paychecks, the deductible, the coinsurance you pay after it, the out-of-pocket maximum, and any employer HSA contribution. Employee-only or family coverage.
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02
Ask in plain words
In ChatGPT with the plugin connected, or any MCP client: "Compare two plans at $5,000 of covered care: Plan A is $300 a month, $1,000 deductible, 20% after it, $5,000 maximum; Plan B is $150 a month, $3,000 deductible, 20%, $6,000 maximum, with a $1,000 employer HSA."
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03
Read the figures and the assumptions
The result lists annual premiums, your cost-sharing at each spending level, the HSA effect, the covered in-network ceiling and any crossing point, with every assumption and any missing term named. Confirm the terms against your plan documents before enrolling.
Questions and answers
What Benefits Compare does with your plan terms.
Straight answers about what Benefits Compare does with your numbers. For the plugins in general, see the main questions page.
What does Tobie Benefits Compare calculate?
It works out what each employer health plan costs you in a year from the terms you give it: annual premiums, your cost-sharing (deductible, then coinsurance, up to the out-of-pocket maximum) at spending levels you choose, the effect of an employer HSA contribution, the covered in-network ceiling, and the spending level where two plans cost the same. Every figure is exact to the cent and comes with its assumptions.
Is Tobie Benefits Compare free? Do I need an account?
Yes, it is free to use, and there is no account, no sign-in and no upload. ChatGPT sends the plan terms from your conversation to the calculator, and the figures come straight back into the chat.
Which numbers do I need to compare health plans?
For each plan: the premium per paycheck and the number of paychecks in the year, the deductible, the coinsurance you pay after the deductible, the out-of-pocket maximum, and any employer HSA contribution. Then pick one or more hypothetical amounts of covered in-network care, such as $1,000, $5,000 and $15,000. If a term is missing, the calculator names it rather than guessing.
How is an employer HSA contribution treated?
As money that can pay for care, never as a discount on premiums. At each spending level the calculator applies the smaller of the HSA balance and your cost-sharing, reports what is left, and shows your cash after the HSA separately from the figure before it.
Does it tell me which plan to choose?
No. It shows what each plan costs under the terms and spending levels you gave it, and a lower number is never a recommendation. It does not decide what a plan covers, whether a provider is in network, or whether you are eligible. Confirm figures with your plan documents and your benefits administrator.
What is the covered in-network ceiling?
Your annual premiums plus the plan's in-network out-of-pocket maximum: the most the modelled terms can cost you in a year for covered in-network care. Out-of-network care, non-covered services and balance billing are outside it, so real costs can be higher.
Can it compare family coverage, not just employee-only?
Yes. For family coverage you describe hypothetical charges per family member, and the calculator applies embedded or aggregate deductibles with the per-person and family limits you state. The simple one-person model is for employee-only coverage.
How does it find the spending level where two plans cost the same?
Exactly, from the two plans' cost curves, rather than by scanning a grid of spending levels. Two plans can cross zero, one or two times; each crossing point is reported to the cent, and "none" means one plan is cheaper at every level.
What happens to the numbers I enter?
Nothing is kept. The calculator stores no inputs, no results, no account and no cookie. A short technical log per request records which tool ran and whether it succeeded, with no amounts and no IP address. Nothing is reported to an employer, and nothing is sent to any AI model by Tobie.
Is it available in the ChatGPT app directory today?
Not yet. The plugin is not listed in ChatGPT yet. Its MCP endpoint, https://plugins.tobie.team/mcp/benefits-compare, is live for developer-mode users and any MCP client. This page will link to the listing the day it is live.
What it does not do
The edges, stated plainly.
The calculator models covered in-network cost-sharing from stated terms. Real plans have rules it cannot see, so real costs can be higher.
- It does not read plan documents, claims, diagnoses or medical records, and it does not ask for them.
- It does not decide what a plan covers, whether a provider is in network, or whether you are eligible for anything.
- It does not include out-of-network care, non-covered services or balance billing.
- It does not model copays per visit in the simple one-person model; copay-based designs use the family ledger or are reported as unsupported.
- It does not enroll you or change anything with your employer.
- It does not pick a plan for you.
- It does not connect to your employer's benefits in this release.
Add it to your ChatGPT
Four clicks, two minutes, nothing to install.
The plugins are not listed in ChatGPT yet. Until they are, you add Benefits Compare to your
own ChatGPT by pasting its address, the same way you would any custom MCP server.
The server is stateless and exposes one tool, compare_health_plans, with a strict
input schema.
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Open chatgpt.com/plugins
Sign in to ChatGPT as usual. Click Add, then Add custom MCP server.
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Name it and paste the address
Name: Tobie Benefits Compare. Under Connection, choose Server URL and paste this address:
https://plugins.tobie.team/mcp/benefits-compare -
Choose no authentication, then create
There is nothing to sign in to. Read ChatGPT's notice, choose I understand and want to continue, then Create as a plugin. ChatGPT shows the one tool it found.
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Use it in any chat
Start a new chat, type @, pick Tobie Benefits Compare, and ask your question in plain words.
Adding a custom MCP server needs a ChatGPT plan that allows it; in a company workspace an admin may need to turn that on. For the other calculator, repeat these steps with https://plugins.tobie.team/mcp/total-rewards.
For developers: any MCP client
curl -s https://plugins.tobie.team/mcp/benefits-compare \
-H 'content-type: application/json' \
-H 'accept: application/json, text/event-stream' \
-d '{"jsonrpc":"2.0","id":1,"method":"tools/list"}'
# One tool: compare_health_plans. Stateless: no session, no cookie.
# Health: https://plugins.tobie.team/healthPrivacy in brief
The calculator accepts only numbers and fixed choices, keeps no record of them, needs no account and sets no cookie. Its technical log contains no amounts and no IP address. Nothing is reported to an employer. Read the privacy notice and terms.
Calculators, not advice
These are calculators, not advice. They do not provide medical, tax, financial or individualized benefits advice, do not decide what a plan covers or whether you are eligible, and do not enroll you in anything. Confirm figures with your plan documents, your offer letter and your benefits administrator.