From The AI CFO newsletter · by airCFO

Build an AI-powered finance function.

Free, read-only Claude tools for startup finance and accounting, organized by the job they do. Start with the Finance Brain Starter Kit: a folder that gives Claude your handbook, your recurring skills, and a review step, so it works the way your team does.

Get the starter kit Browse the tools

Built by airCFO, the AI-enabled back-office growth partner for startups — on the same context model our team runs on our own books.

How it fits together

Build your Finance Brain

Download the free starter kit. Claude drafts your handbook from your docs and books, then asks you only what they can't answer.

Connect your stack

Add Stripe, Ramp, and Mercury once, read-only, with your own logins. Every tool that needs them shares them.

Run the workflows

Runway, revenue tie-outs, board metrics, and more as they ship. Each reads your Finance Brain before it touches a number.

Build your own

Turn the workflows your team already runs into skills of your own, built to the same standards.

Connected stack

Connect Stripe, Ramp, and Mercury once, read-only, with your own logins. Every tool that needs them shares these connectors.

All Systems Go

Connects Stripe, Ramp, and Mercury to Claude — read-only, with your own logins — and adds the cross-system workflows that need them. Named for airCFO's All Systems Go series on the startup back-office stack.

Plugin · Stripe, Ramp, Mercury

Cash & runway

How much cash you have, how fast it's going, and how long it lasts.

Runway & burn

Net monthly burn, months of runway, and an estimated cash-out date, from your bank's complete cash flows, with Ramp explaining what's driving the number.

/runway-and-burn · Mercury, Ramp, Stripe

Revenue & close

Tie revenue across systems and explain every gap before the books close.

Revenue reconciliation

Tie Stripe revenue to QuickBooks recognized revenue with an explicit bridge, and turn every unexplained difference into an open item with a next step.

/revenue-reconciliation · Stripe, QuickBooks

Reporting

Board- and investor-ready numbers, built from your own definitions.

Board metrics

A paste-ready monthly metrics pack (ARR and MRR, cash, burn, runway, and AR/AP aging) with a short narrative on the trend that matters most.

/board-metrics · Stripe, Mercury, Ramp, QuickBooks

Build your own

Turn the workflows your team already runs into skills of your own.

Finance skill builder

Turn a workflow your team already runs (a flux review, a vendor check, a monthly tie-out) into a reusable skill of your own, built to the same standards as the tools in this library.

/finance-skill-builder

Finance skill tuner

Fix a skill that isn't behaving (won't trigger, fires when it shouldn't, skips a check, or returns the wrong format) with a plain-language diagnosis and a minimal fix.

/finance-skill-tuner

Read-only by design

Every tool reads your systems with your own login and never writes to them. No journal entries, no payments, no subscription changes. Outputs are analysis for a human to review, and anything a tool couldn’t verify shows up as an open question instead of a confident guess.

Every connector is the vendor’s own, authorized with your own login. airCFO runs no server in between, and your Finance Brain is a folder on your machine. Data handling and security

Install once, add tools anytime

Everything runs in Claude Cowork, the Cowork tab in the Claude desktop app, on Pro, Max, Team, and Enterprise plans. The starter kit is a download: nothing to install. For the tools, add the airCFO marketplace once, and every tool after that is a one-click install. Each tool’s page lists exactly which plugins it needs, in order.

Documentation

Finance Brain Starter Kit: download it and get set up in Cowork.
Example handbook: the kit filled in for a fictional Series A company.
Prompts to try: including ad-hoc analyses with no dedicated tool yet.
Data handling and security: read before you connect anything.
Known limitations: the honest list.