Cash runway monitor
By Toolspoke
Reads Mercury every Monday, works out net burn and months of runway, logs them to a Google Sheet and posts a short Slack summary.
Needs a Toolspoke account. You choose which project it installs into.
- Mercury + Google Sheets + Slack
- Required integrations
- Runs on a schedule
- Mondays at 8am by default
- Post one message
- What its last step does
- Some actions can delete
- 4 of 40 actions in its tools
On this page
The short version
- What it is
- A ready-made Toolspoke agent that works out your cash runway from Mercury each week and keeps a history of it.
- What it reads
- Account and Treasury balances and the last 90 days of posted transactions, with their categories.
- What it writes
- One row a week, appended to a Google Sheet tab chosen when you set it up.
- Where it posts
- One Slack channel, chosen when you set it up.
- What it reports
- Cash, average monthly net burn, runway in months, the change since last week and the three spend categories that moved most.
- How often
- Every Monday at 8am once you switch it on.
- What it never does
- Move money, change a transaction, cancel an invoice or edit the history already in the sheet.
- What you need
- A Toolspoke account, a Mercury API token (read only is enough), a Google account and a Slack workspace.
What Cash runway monitor does
Cash runway monitor is an AI agent that reads Mercury every Monday, works out how fast the company is spending cash and how long it lasts, and posts the answer to Slack with a running history in a Google Sheet.
Runway is the number a founder most needs and least often checks, because working it out means exporting transactions, removing the transfers between your own accounts and arguing with a spreadsheet.
Cash runway monitor does that every week in the same way. It reads the balances, takes 90 days of transactions, leaves out transfers between your own accounts and works out average monthly net burn. Runway is cash divided by that burn.
Because the method never changes, the weekly number is comparable with last week's. The history sheet shows the trend, and the Slack post says what moved it.
In practice, every Monday morning you get:
- Cash across your Mercury accounts, including Treasury
- Average monthly net burn over the last three months
- Runway in months, and the change since last week
- The three spend categories that moved most
How it works
Cash runway monitor works in four steps each Monday: it reads balances and transactions, works out burn and runway, adds a row to the history and posts a summary. All of it comes from the agent's written instructions, which you can read and edit after you install it.
- M
Step 1: Read balances and spend
It reads every account, Treasury, and 90 days of posted transactions.
Step 2: Work out burn
It leaves out your own transfers and averages three months of net burn.
Step 3: Log the week
It appends one row to your history sheet.
Step 4: Post a summary
It posts cash, burn, runway and what moved.
It counts every account you keep
Cash is the sum of current balances from list_accounts and list_treasury_accounts, leaving out any account you name at install, such as one that holds customer deposits.
It leaves out your own transfers
A transfer from checking to savings, or into Treasury, is not spending. The agent matches both halves by amount, date and account and leaves them out, so moving money around does not look like burn.
It averages three months
It reads 90 days of posted transactions with list_transactions and works out money in minus money out for each 30 day month. Average net burn is the mean of the three, and runway is cash divided by it. If the company is cash positive, it says so and gives no runway.
It only adds to the history
Each week it appends one row with append_rows: date, cash, burn, runway and the categories that moved. It never edits or clears rows that are already there. The limits are listed under what it will never do.
What a Monday summary looks like
A message from Cash runway monitor is a short Slack post: the headline numbers, the change since last week, and what moved.
Fernhill
Channels
- # finance
- # founders
- # ops
- # general
# finance
Monday 4 November. Burn is the average of the last three months; runway applies it to today's cash.
Runway
**17.4 months**, down 0.3 on last week.
What moved (last 30 days against the 30 before)
- Payroll, 61,300, up 12% from 54,700.
- Software, 7,900, down 18% from 9,600.
- Uncategorised, 4,100, up from 1,200.
The numbers
Cash 1,465,000. Net burn 84,200 a month. Row added to the history sheet.
- Runway
Months of cash at the current burn, and how it changed since last week's row in the sheet.
- What moved
The three spend categories with the largest change in money, up or down, with both amounts. Uncategorised spend counts as its own category.
- The numbers
Cash and average monthly net burn, the two figures runway comes from, so anyone can check the sum.
Why it always posts
Runway is a number you want every week, including the weeks it did not move. A steady line in the history is information too.
A failed run is different. If Mercury cannot be read, it posts that once and adds no row, so the history never holds a made-up week.
Who uses Cash runway monitor
Cash runway monitor suits any company that banks with Mercury and wants its runway without building a model. The examples use made-up names.
A founder between fundraises
Elif Demir needs to know when to start raising. The weekly runway, and its change, tell her before the board asks.
A part-time finance lead
Marcus Webb works two days a week. The Monday post tells him which category to look at first.
A board update writer
Nadia Haddad copies the trend from the history sheet into the monthly board update, instead of rebuilding it each time.
A team cleaning up categories
Ola Nilsen wants fewer uncategorised transactions. Seeing the uncategorised total each week keeps it from creeping up.
What Cash runway monitor connects to
Cash runway monitor connects to three tools: it reads Mercury, appends to a Google Sheet and posts to Slack. You connect each one yourself, and Toolspoke stores the connection encrypted, so the agent never sees the credential.
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Mercury
RequiredRead bank accounts, balances, transactions, statements, recipients and receivables invoices.
Authentication: API token
Google Sheets
RequiredRead and write spreadsheet ranges, append rows, add sheets, and create new spreadsheets.
Authentication: Sign in with Google
Slack
RequiredSearch conversations and send messages to your workspace.
Authentication: Bot token
| Tool | What Cash runway monitor does | What it cannot do |
|---|---|---|
| Mercury | Reads balances, Treasury, transactions and categories (list_accounts, get_account, list_treasury_accounts, list_transactions, list_categories). | Move money, pay a recipient or request a payment: the connector has no action for any of them. It can change a transaction's note or category and cancel an invoice, which this agent's instructions forbid. |
| Google Sheets | Appends one row a week with append_rows. | Delete a spreadsheet: the connector has no delete action. It can overwrite or clear ranges, which this agent's instructions forbid. |
| Slack | Posts one message with send_message, to a channel. | Delete messages: the connector has no delete action. |
The Mercury connection cannot move money, which is a property of the connector. Its two changing actions, update_transaction and cancel_invoice, are ones the agent is told not to use. For a lock, connect a Mercury Read Only token, or switch those actions off in your project. The access control guide explains how.
Appending only to the sheet is an instruction. Switch off the Google Sheets update, clear and batch update actions in your project if you want that enforced.
The activity log records each call, but Mercury reads that name a counterparty keep only that the call happened. The message posted to Slack is stored.
What Cash runway monitor will never do
Cash runway monitor cannot move money, and is told never to change a transaction, cancel an invoice or edit the history in the sheet. It reads and reports.
- Move money, pay a recipient, or request a payment.
- Change a transaction's note or category, or cancel an invoice.
- Overwrite, clear or reorder the history in the sheet.
- Present runway as a forecast.
- Post account numbers, routing numbers or recipients' bank details.
Why it cannot move money
The Mercury connector has no payment, transfer or recipient action. Even a mistaken instruction has nothing to call.
Why it does not tidy your books
Recategorising a transaction would make the numbers look better without changing the cash. The agent reports uncategorised spend and leaves the fix to a person.
Why runway is not a forecast
Runway here is last quarter's burn applied to today's cash. It does not know about a hire you plan or a contract you expect. The post says so, so nobody reads it as a promise.
If something goes wrong
If Mercury cannot be read, post that once and do not add a row. If the sheet cannot be written, post the summary anyway and say the history was not updated. If fewer than 90 days of transactions exist, use what there is, say how many days, and mark the runway as early.
These are written into Cash runway monitor's instructions. They guide the agent, but they are not a permission. What it is allowed to touch is set by the access you grant.
Cash runway monitor reads Mercury and reports what it finds. Every payment and every change to your books stays with a person.
When Cash runway monitor runs
Cash runway monitor runs every Monday at 8am, but only after you switch its schedule on. It arrives switched off, so nothing runs and nothing is charged until you decide.
- Each run reads today's balances and the last 90 days of transactions.
- Each run appends one row to the history sheet.
- Each run posts one short summary to Slack.
- If Mercury cannot be read, it posts that once and adds no row.
Each run uses model credit from your workspace balance, so it makes one run a week. The Mercury, Google Sheets and Slack calls themselves are free.
Your copy is an ordinary agent in your project. You can pause its schedule there, run it once on demand, change the day and time and edit its instructions. The agent's page lists recent runs and their cost.
How to set up Cash runway monitor
To track runway each week, add Cash runway monitor to a Toolspoke project, connect Mercury, Google Sheets and Slack, choose where it writes and posts, and switch on the schedule. It takes a few minutes, and nothing runs until the last step.
Step 1: Create a Toolspoke account or sign in
Choose Use this agent. If you are new, you will be asked to sign up first, and you come straight back to this agent afterwards.
Step 2: Add it to a project
Pick the project it should live in. You get your own editable copy, and you can see the three tools it brings before anything connects.
Step 3: Connect Mercury
Create a Read Only API token in Mercury and paste it. It is stored encrypted and the agent never sees it.
Step 4: Connect Google Sheets
Choose Sign in with Google, then create a sheet with a tab for the history, or pick an existing one.
Step 5: Connect Slack
Choose Sign in with Slack and approve the Toolspoke app. For a private channel, add the Toolspoke bot to it first.
Step 6: Name the sheet, channel and accounts to leave out
Put the sheet, tab, channel and any Mercury accounts to leave out in the instructions.
Step 7: Switch on the schedule
The schedule arrives switched off. Run it once to see the first row and post, then switch it on.
Make Cash runway monitor fit your company
Cash runway monitor's instructions are plain English and you can edit them after you install it. Installing copies the agent, so your edits stay with your copy. Open the agent in Toolspoke and tell the builder what to change, and it rewrites the instructions.
Paste any sentence below into the builder chat, or say the same thing in your own words.
Average net burn over the last 180 days, not 90.
Leave out incoming payments from our investors when working out burn.
Start the post with a warning when runway is below 12 months.
Run on the first day of each month at 8 AM instead of weekly.
This changes when the agent wakes up, so the builder edits its schedule, not the instructions.
List the five categories that moved most, not three.
None of these edits needs more access or touches the Never rules. They change what Cash runway monitor is told, not what the connections allow.
How it compares to other options
Cash runway monitor beats the alternatives when you want the same runway sum every week with a history, and loses to them when you need a forecast that knows your plans.
| Compared on | Cash runway monitor | Mercury's dashboard | A finance model in a spreadsheet | A fractional CFO |
|---|---|---|---|---|
| Runway in months, every week | Yes | Balances, not runway | When you update it | Usually monthly |
| Leaves out your own transfers | Yes | Partly | If you remove them | Yes |
| Keeps a weekly history | Yes, in your sheet | No | If you keep one | Yes |
| Knows your hiring and revenue plans | No | No | Yes | Yes |
| Can move money | No, the connector cannot | Yes | No | Depends on access |
| Setup effort | Connect three accounts | None | Build and maintain it | An engagement |
A finance model is the better choice for planning: it can include a hire you have not made yet. Cash runway monitor tells you what last quarter's spending means for today's cash.
A fractional CFO gives judgement as well as numbers. Many use a weekly figure like this one as the starting point.
Frequently asked questions
Can Cash runway monitor move money?
No. The Mercury connector has no payment, transfer or recipient action, so the connection cannot move money.
What does it change in Mercury?
Nothing. The Mercury connection can change a transaction's note or category and cancel an invoice, and the agent is told never to. For certainty, use a Read Only token or switch those actions off (how access works).
How is runway worked out?
Cash across the accounts you include, divided by average monthly net burn over the last 90 days, with transfers between your own accounts left out.
Can it overwrite my sheet?
It is told only to append one row a week, never to edit or clear rows. The Google Sheets connection could overwrite ranges, so switch those actions off in your project if you want that enforced.
What if we are cash positive?
It says so and does not give a runway, because there is no burn to divide by.
What if the account is less than 90 days old?
It uses the days there are, says how many, and marks the runway as early.
Is Cash runway monitor free?
It has no price of its own, and every Toolspoke plan includes agents. Tool calls cost nothing, but each run draws on your usage balance. Pricing has the details.
Know your runway every Monday
Connect Mercury, Google Sheets and Slack, choose where it writes and posts, and switch on the schedule. Your first summary lands on Monday at 8am.