Everything on screen is in the API
Read the numbers into your own tools, write what only your product knows, and react to what happens. Bearer tokens, JSON, decimal amounts with an explicit currency.
Start free Read the API reference Free during early access. Read-only Stripe key, hosted in Germany.
Read
MRR by month with movements and the effect of exchange rates, every movement with its causes and Stripe references, customers with status, MRR and ARR, revenue at risk, notes, tasks, events.
Write
Create and update customers by your own id - leads, trials, product usage, owner, tags, contacts. Name the Stripe customer and the record that already mirrors it is adopted with its whole history instead of a duplicate being created. Notes, calls and tasks can be written again and again under your own id without doubling.
React
Events list what happened to customers, oldest first, for tools that poll. Automations and their webhook action push the same events to you, signed with HMAC-SHA256.
Ask Claude
sumwerk is also a Model Context Protocol server. Connect Claude with a token and ask in plain language which paying customers stopped using the product, why MRR dropped last month, or what is known about a customer before a call. It reads the same numbers the pages show, and with a read-only token it can only read.
Raw data for spreadsheets
Every movement, every month, the funnel, segments and customers are CSV files too. The customer file has one column per custom attribute and follows the filter on screen, so an analyst gets exactly the rows they were looking at.
Tokens with a scope
A token is read-only or read-and-write, shown once, stored hashed and revocable at any time. 600 requests per minute per token.
Sandboxes, like the ones you know from Stripe
One for staging, one for every developer: a sandbox has the same team and settings as your account, and its own customers, numbers and API tokens. Point a system at it with a token that starts with swk_test_, connect Stripe's test mode, try an automation or an import. No email leaves it, and because a sandbox is a separate account and not a flag, test data cannot end up in your MRR.
Questions
- How do I connect Claude?
- With one command or a few lines of configuration and an API token. The guide is in the docs under "Ask Claude about your customers".
- Is there a sandbox?
- Create a second account and connect a Stripe test-mode key.
- Are there CSV exports too?
- Yes - months, movements and customers, from the overview.
Goes well with
- AutomationsWhen a trial starts, a payment fails or a cancellation is scheduled, sumwerk adds a task, sets the owner, tags the customer or calls your webhook.
- CustomersA customer in sumwerk exists independent of Stripe: leads and trials from your product, several Stripe customers under one record, attributes, tags, owners.
- MRR you can provesumwerk computes MRR from the state of each Stripe subscription, not from prorated invoices, and links every movement to the Stripe invoice or event behind it.
Connect Stripe and check your own numbers
A restricted, read-only key is all it takes. The first import runs in a few minutes; every number you see opens into the customers and Stripe references behind it.