MCP Server

Connect Claude, ChatGPT or any MCP client to the engines behind my web models and spreadsheets. You ask in plain words, your AI fills in the terms, and the numbers come from tested code rather than from the model's best guess. Sign in and it works on the cap tables, waterfalls, fund models and forecasts you've saved, too.

23 toolsFree to connectListed in the MCP registry

Free

Run a calculation in chat without an account, 3 times a day. Sign in to work on your saved models. Direct engine calls for agents are $20/year after 10 free.

Connect in Claude

Or paste this into any MCP client:

https://mcp.hemrock.com/mcp/account

ChatGPT, Claude Code, Cursor REST API reference The skill, with nothing to connect

Series A and exit

Two founders hold 6M and 4M shares. We raised a $1M post-money SAFE at a $10M cap, and now we're raising a $5M Series A at $20M pre with a 10% pool. Show me the cap table, then who gets what if we sell for $60M or $15M.

Used 3 Hemrock toolscap_table_computeexit_waterfall_computeexit_waterfall_compute

The Series A prices at $1.575 a share, and the SAFE converts at $0.90.

After the round	Fully diluted
Founder A	37.8%
Founder B	25.2%
Series A lead	20.0%
Option pool	10.0%
SAFE investors	7.0%

Proceeds	$60M sale	$15M sale
Founder A	$25.2M	$5.4M
Founder B	$16.8M	$3.6M
Series A lead	$13.3M	$5.0M
SAFE investors	$4.7M	$1.0M

At $60M the Series A converts, because $4.20 a share beats its 1x preference. At $15M it takes the preference instead and common gets $0.90 a share. The pool is unissued, so it gets nothing either way.

Work on the models you saved

The cap tables, waterfalls, fund models and forecasts you save in the browser are in your account, and your AI can find them by name. It opens one, makes the change you describe, runs it and saves it, and the builder shows the new version next time you open it. It can start new ones for you as well. That's free, the same as using the builder.

Open my Example Fund I model and raise the fee to 2.5%. What does that do to LP returns?

Used 3 Hemrock toolslist_saved_modelsupdate_saved_modelrun_saved_model

	2.0% fee	2.5% fee
Management fees	$4.9M	$6.1M
Invested capital	$21.4M	$20.2M
Net multiple to LPs	2.85x	2.69x
Net IRR to LPs	23.2%	22.2%

Saved. The extra fee comes out of what gets invested, so LPs give up about 0.16x. It's waiting in your fund builder with the new fee.

Connect

Paste the URL into your AI client as a connector. It asks you to sign in to Hemrock, or to create a free account, and then every tool is there. It takes about a minute.

https://mcp.hemrock.com/mcp/account

ClaudeSettings, then Connectors, then Add custom connector. Works in claude.ai and the desktop app.ChatGPTSettings, then Connectors, then add a custom MCP connector and paste the URL.

Claude Code

Add the server, then run /mcp inside Claude Code to sign in.

claude mcp add --transport http hemrock https://mcp.hemrock.com/mcp/account

Cursor and other clients

Most clients take a JSON entry like this one.

json

{
  "mcpServers": {
    "hemrock": {
      "url": "https://mcp.hemrock.com/mcp/account"
    }
  }
}

Your own code

The same engines are a REST API. Create a key under Developer access and read the API reference. A client that can send headers but can't sign in can use the key with https://mcp.hemrock.com/mcp too.

One model, four ways in

Each model is one product. The web builder, the API and this server run the same code, and the spreadsheet holds the same structure as formulas you can read. Start a cap table in the browser, ask your AI about it later, and hand the spreadsheet to your lawyer.

Cap Table & Exit Waterfall

Rounds, SAFEs, notes and pools, then who gets what at exit.

Browser

Spreadsheet

Excel and Sheets

Your AI

cap_table_compute
exit_waterfall_compute

Your code

POST /v1/cap-table/compute
POST /v1/exit-waterfall/compute

Venture Capital Model

A fund over time: calls, fees, carry, NAV, the J-curve and IRRs.

Browser

Fund builder

Spreadsheet

Excel and Sheets

Your AI

fund_economics_compute

Your code

POST /v1/fund-economics/compute

Every other model

Standard, SaaS, Ecommerce, Runway. Your AI edits the spreadsheet with Hemrock's guidance.

Browser

–

Spreadsheet

Your AI

get_context
get_prompts
get_checks

Your code

–

The free Fund Economics Tool spreadsheet is the high-level version of the same fund math.

More from the chat

A few more conversations, with the tools each one called. The figures are what the engines returned for these prompts.

Forecast a fund

Model a $40M fund with a 2.5% fee, 20% carry and 15% recycling. Keep your defaults for everything else.

Used 1 Hemrock toolfund_economics_compute

Lifetime
Gross multiple	4.00x
Net multiple to LPs	2.87x
Net IRR to LPs, from cash flows	23.3%
Management fees	$9.8M
Carry to the GP	$18.3M

I also have it by year, with calls, distributions, NAV and the J-curve.

Take it into a spreadsheet

Now give me that as an Excel file I can edit. Call it Example Fund I.

Used 1 Hemrock toolfund_economics_compute

Example Fund I.xlsxDownload link, valid 24 hours

Every number is a formula back to the Get Started sheet, so change an input and it flows through. It's the same file the web model exports.

Check a model your AI edited

I had AI rework the fees in my Venture Capital Model. Check it before I send it to my LPs.

Used 1 Hemrock toolget_checks

I'll go through these against your file, one at a time:

Validate invested capital vs fund size
Validate TVPI is net, not gross
Validate the waterfall carry calculation
Validate NAV reaches zero at fund end

Set up a spreadsheet model

I just downloaded the Standard Financial Model. Help me set it up for a subscription business.

Used 2 Hemrock toolsget_contextget_prompts

I have the primer for this template, so I know which cells are inputs. Let's go in this order:

Find all input cells
Configure revenue model for my business
Set up churn and retention inputs
Set up hiring plan

All 23 tools

Guidance needs no account. Your saved models need you signed in and cost nothing. The cap table, waterfall and fund engines run 3 times a day without an account, and each result comes with a link that opens it in the builder and saves it to your account. They are the only metered tools. The founder models share those daily runs without an account and are free once you sign in.

Your saved models6

List saved modelsSign inlist_saved_models

The cap tables, waterfalls, fund models and forecasts in your account, and fund models shared with you.

Open a saved modelSign inget_saved_model

Its events, cap stack or fund inputs, in the shape the engines take.

Run a saved modelSign inrun_saved_model

Calculates it as it stands, with the Excel workbook for a fund if your account has the export.

Change a saved modelSign inupdate_saved_model

Saves an edit. The browser builder shows it the next time you open the model.

Save a new modelSign increate_saved_model

Keeps something you built in chat, so you can pick it up in the browser.

Check in on saved modelsSign incheck_in

What's worth a look across your recent models today, with the numbers, plus workshops and services that fit. Made for assistants that check in on a schedule.

Run the engines8

Compute a cap tableFree to trycap_table_compute

Ownership after every founder grant, pool, SAFE, note, warrant and priced round.

Compute an exit waterfallFree to tryexit_waterfall_compute

Proceeds by holder for one sale price, with preferences, participation, seniority and conversion.

Compute fund economicsFree to tryfund_economics_compute

Lifetime totals and the fund by year or quarter. Ask for the live Excel workbook and it returns a download link.

Compute unit economicsFreeunit_economics_compute

LTV, LTV to CAC and CAC payback for recurring, one-time and repeat revenue, with one customer's cash flow by month.

Forecast a SaaS businessFreesaas_forecast_compute

Subscribers, MRR, ARR, billings and deferred revenue for 12 to 120 months, on one churn rate or a cohort retention curve, with a link that opens the same inputs in the web model.

Forecast an ecommerce businessFreeecommerce_forecast_compute

Orders, revenue and margin built from monthly customer cohorts, on a retention curve you describe month by month or build from churn.

List the enginesNo accountlist_models

What can run directly and what it costs. No account needed.

Get accessNo accountget_access

Whether a model is free or paid, the price, and a checkout link for you to open.

Guide edits to a spreadsheet4

Get modeling contextNo accountget_context

The primer for a Hemrock template, read before your AI touches a cell.

Get task promptsNo accountget_prompts

Prompts for one job in one template: set up revenue, model a round, prepare for investors.

Get validation checksNo accountget_checks

Where AI edits to financial models tend to break, as checks your AI runs against your file.

Get best practicesNo accountget_best_practices

Formatting, structure, inputs, assumptions, review and sharing.

Learn the method2

List conceptsNo accountlist_concepts

An index of the concept guides: waterfalls, anti-dilution, notes, cohorts and more.

Read a conceptNo accountget_concept

The full guide on how one calculation works, so your AI can explain it or audit it.

Your account2

Account accessSign inget_account_access

Direct engine calls left, free and paid, and when your term renews.

Account usageSign inget_account_usage

What you have run, by product.

Get a person on it1

Request a reviewNo accountrequest_review

A working session, custom model work or fractional CFO, with the live price and the link to book. Your AI offers it; you book it.

Shortcuts4

Clients that support MCP prompts show these as slash commands.

/hemrock:model_a_round

Asks for the terms it needs, then builds the cap table through the round.

/hemrock:exit_waterfall

Gathers the cap stack and a sale price, then runs the waterfall.

/hemrock:fund_returns

Collects your fund terms and forecasts fees, carry and net returns.

/hemrock:review_my_model

Works through the checks against your model. Free, no sign-in.

Pricing

Connecting is free, and so is almost everything you'll do with it. I only charge for direct engine calls, which is how an agent or your own code runs the models at volume.

Guidance and concept toolsFreePrimers, prompts, checks and concept guides. No account needed.

Your saved modelsFreeList, open, change, run and create models in your account, the same as the browser builders. Sign in to use them.

Direct engine calls$20/yearcap_table_compute, exit_waterfall_compute and fund_economics_compute, over MCP or the API. 3 a day free without an account, 10 free per product once you sign in, then 6,000 a year.

The direct-call allowance is per product: Cap Table & Exit Waterfall share one, and Fund Economics has its own. When it runs out your AI tells you and hands you a checkout link. You pay on hemrock.com and your AI never sees a card. Nothing is charged automatically when you run out. Running more than that? Get in touch and I'll work out a plan with you.

Questions

Which URL do I add?

The account URL, https://mcp.hemrock.com/mcp/account. It has every tool and asks you to sign in when you add it. If you only want the free guidance tools and no account, use https://mcp.hemrock.com/mcp.

Do I need an API key?

Not for a connector. Claude and ChatGPT sign you in to Hemrock when you add the URL, and that sign-in is what the engines run on. You need a key for your own code, or for a client that can send headers but can't sign in. Create one under Developer access and send it as Authorization: Bearer hk_live_….

Can my AI work on the models I saved?

Yes. Sign in and your AI can list the cap tables, waterfalls, fund models and forecasts in your account, open one, change it, run it and save new ones. They're the same saved models the browser builders use, so a change made in chat is there when you open the model on the web. Fund models someone shared with you show up too, with the same editing rights you have in the browser. All of that is free.

Does it open my spreadsheet?

No. The engines run on Hemrock's servers from the inputs your AI sends, the same way the web models do. To work in your own file, your AI uses the guidance tools against it. If you want the fund as a spreadsheet, ask for the workbook and you get a live Excel file with every number a formula.

What's MCP?

The Model Context Protocol, an open standard for giving an AI client tools it can call. Claude, ChatGPT, Cursor and most coding agents speak it. The server is listed in the MCP registry.

MCP or the skill?

The skill is the guidance packaged for Claude, with nothing to connect. The MCP server has the same guidance plus the live engines, and it works outside Claude too. If you want numbers computed, use MCP.

Is there a ChatGPT app?

Two focused apps are on the way, one for cap tables and waterfalls and one for fund economics. Until they're listed, add the account URL as a connector in ChatGPT and you get the same engines.

Free

Run a calculation in chat without an account, 3 times a day. Sign in to work on your saved models. Direct engine calls for agents are $20/year after 10 free.

Connect in Claude

Or paste this into any MCP client:

https://mcp.hemrock.com/mcp/account

ChatGPT, Claude Code, Cursor REST API reference The skill, with nothing to connect