Choose your way to use a service

A published service can be used in several ways at the same time. This page helps you pick the one that fits what you want to do.

The short answer

All ways use the same published service, the same inputs and outputs, and the same limits. You do not have to decide once and for all.

The API

Choose the API when a developer builds the calculation into an application, a website back end or a script. A call sends the inputs and gets JSON back. The API tab has a tester, ready-made code for cURL, JavaScript and Python, and an interactive documentation.

Good for: quote engines, price calculation in a shop, checks in an internal tool.

An AI assistant

Choose the AI connection when people ask questions in Claude, ChatGPT or another assistant and the answer must be calculated, not guessed. There are three ways, depending on whose AI it is:

• Your own AI, connected to your account. It reaches the services you allow and can also build new ones.
• Someone else's AI, through the MCP address of one service.
• Any agent that can open an address, through the discovery address of the service.

Before you connect an AI, describe the service under AI → Definition so the assistant knows when to use it and what each value means. See AI definition.

The web app

Choose the web app when people should simply fill in fields and see results. SpreadAPI generates the page from your inputs and outputs; you share it by link or QR code. See Apps overview.

Good for: a calculator for the sales team, a quick tool for customers, a form on a phone.

A web snippet

Choose a snippet when the calculator should appear inside your own website, blog or documentation. You copy an embed code into the page. The theme you pick under Apps → Theme applies to the web app and the snippets.

An automation tool

Choose an automation tool when the calculation is one step among others: a form is submitted, the price is calculated, an email goes out. SpreadAPI has connectors for n8n, Zapier and Power Automate under API → Automation (Automatisierung). Other tools with an HTTP step, such as Make, call the API directly; see Other tools over HTTP.

Excel or Google Sheets as a client

Choose this when the results should land in another spreadsheet, for example a light workbook for colleagues that asks your service for the numbers. API → Code has ready-made formulas for Excel and Google Sheets.

What applies to every way

• The service must be published. See Publish and republish.
• A protected service needs a token on every call; an AI connected to your account reaches it without one. See Tokens and access.
• Calls over every way count towards the calls of your plan. See Call limits.
• The Usage (Nutzung) tab shows the calls split by channel: API, AI and web app.

For developers and agents

• REST: https://spreadapi.io/api/v1/services/{serviceId}/execute, GET with query parameters or POST with {"inputs": {...}}.
• An OpenAPI file is available for code generators and tools such as Postman; see OpenAPI and interactive docs.
• An agent without an MCP client can read the discovery address of a service and call it over plain HTTP; see Discovery address.
• An agent connected to the account can list, create, test, publish and run services; see What a connected agent can do.

FAQ

Which way should I start with?

Start with the API → Test page to see your service answer, then pick by audience: the API for developers, the web app for people, the AI connection for assistants, an automation tool for workflows. You can use several at once.

Can I use the API and the web app for the same service?

Yes. All ways run on the same published service at the same time, and the Usage tab shows the calls of each channel.

I cannot program. Which ways work for me?

The web app, the web snippets, the AI connection and the automation tools work without writing code. You only choose inputs and outputs and publish.

How do I put a calculator on my website?

Use a web snippet: open the Apps tab, choose Web Snippets, and copy the embed code into your page. See Web snippets.

Can I use my service in Make?

Yes, through an HTTP step that calls the API address of the service. See Other tools over HTTP.

Should I give my customer the API or the MCP address?

Give a developer the API address and, if the service is protected, a token. Give someone who works in an AI assistant the MCP address of the service; see The MCP address of a service.

Do the different ways cost extra?

No. Every plan includes the API, the AI integration, the apps and the automation connectors; the plans differ in published services, workbook size and calls per month. See Plans overview.

I am an agent and my user gave me a service address. How do I use it?

If you have an MCP client, add the MCP address of the service as a server. Otherwise open the discovery address with GET to read the inputs and outputs, then send the calculation with POST.