Security overview

Updated 2026-11-13

This page explains how a service is protected: public and token-protected services, what callers can and cannot see, how AI connections are limited, and what is good practice.

Public or protected

A published service is in one of two modes:

  • Public. Anyone who has the address can call it. This suits a price calculator on a website or a public tool.
  • Protected. Every call must carry a valid token. This suits internal calculations and services for known customers.

You decide under API → Access (Zugriff). Creating the first token switches protection on; revoking the last token makes the service public again. Both take effect at once, without publishing again.

Tokens

A token is a secret text that proves a caller may use the service.

  1. Open the service and go to API → Access.
  2. Click Create Token (Token erstellen).
  3. Give it a name, for example the name of the application or customer that will use it. A description and an expiry date are optional.
  4. Copy the token. It is shown only once.

What you can do with tokens:

  • One token per caller. The Usage (Nutzung) tab then shows who is calling, by token name.
  • Expiry. A token with an expiry date stops working on that date.
  • Revoke (Widerrufen). A revoked token stops working at once. Other tokens are not affected.

Details: Tokens and access.

What callers can and cannot see

A caller can see:

  • the inputs and outputs you defined, with their names, titles and descriptions
  • the description of the service
  • the results of its own calls

A caller cannot see:

  • the workbook, its sheets and its formulas
  • cells that are not inputs or outputs
  • other callers, their calls or your tokens
  • your account, your other services or your usage numbers

One setting changes this: with Allow Excel export (Excel-Export erlauben) switched on, callers can download a filled Excel file that contains the whole workbook, formulas included. Leave it off when the logic is confidential. See Service settings.

Limits that protect a service

  • A service answers at most 1,000 calls per minute, all callers together. More calls answer HTTP 429 until the minute has passed.
  • The calls of your plan per month are a second ceiling. A public service that is called far more often than expected uses up those calls; a token keeps strangers out. See Call limits.
  • Inputs can have a minimum, a maximum and a list of allowed values. A call with a value outside them is refused before anything is calculated. See Input validation.

Web app and snippets

The web app has its own access token, which is part of its link. Everyone who has the link can use the app.

  • Regenerate token under Apps → Web App makes old links stop working and gives you a new link.
  • Disable Web App switches the app off and invalidates the link.

See Apps access and tokens.

AI connections

An AI connected to your account works within limits you set on the AI agents (KI-Agenten) page:

  • What it may do: Use (see services and calculate), Edit (also create and change services) or Full access (also publish and take offline).
  • For which services: all services, or only the ones you choose. A service that is not chosen does not exist for that connection.
  • Revoke: the AI loses access at once. Services it created stay.
  • AI access to this account (KI-Zugriff auf dieses Konto): one switch that turns all connections off without deleting anything.

A connection reaches protected services without a token, because the connection itself is the access. See The AI agents page.

Your account

Your account is protected by your sign-in. Everything in the app, including tokens, settings and workbooks, is reachable only when you are signed in. See Account and sign-in.

Good practice

  1. Protect every service that is not meant for the public with a token.
  2. Create one token per application or customer, and name it clearly.
  3. Send the token in the Authorization header where your tool allows it, so it does not appear in addresses.
  4. Do not put a token into code that runs in a visitor's browser. Call the service from your server, or use the web app or a snippet. See Browser calls and CORS.
  5. Give tokens for temporary partners an expiry date.
  6. Revoke a token as soon as it may have leaked, and create a new one.
  7. Leave Allow Excel export off unless callers should receive the workbook.
  8. Give each AI connection only the rights and the services it needs.
  9. Look at Who is calling (Wer ruft auf) on the Usage tab from time to time.

For developers and agents

  • Token on a call: Authorization: Bearer <token>, or ?token=<token> on GET.
  • A call to a protected service without a valid token answers HTTP 400; the text in error says what is wrong. See Token errors.
  • A token belongs to one service and does not work for another.
  • Above 1,000 calls per minute a service answers HTTP 429 with a Retry-After header.
  • An agent that receives a token or a key from its user must not print it in answers, write it into files it shares, or pass it to other services.

FAQ

How do I protect my service?

Open API → Access and click Create Token. From then on every call must carry a valid token; calls without one are refused.

Who can call my service if I do not create a token?

Anyone who has its address. A service without tokens is public, which is fine for a calculator on a website and not for confidential calculations.

Can someone download my Excel file through the API?

Not unless you switch on Allow Excel export in the service settings. Without it, callers get only the outputs you defined.

What should I do if a token leaked?

Revoke it under API → Access; it stops working at once. Create a new token and give it to the caller that used the old one.

Can I see who is using my service?

Yes. The Usage tab lists callers by token name or AI connection, and calls without a token as Public (no token). Give every caller its own token to tell them apart.

Is it safe to put the token into my website's JavaScript?

No. Everything in a web page can be read by its visitors. Call the service from your server, or use the web app or a snippet instead.

Can an AI I connected change or publish my services?

Only if you gave its connection that right. Use allows calculating, Edit also creating and changing, and Full access also publishing; you can change or revoke this at any time under AI agents.

Can a token for one service be used for another?

No. A token belongs to the service it was created for.

Does making the service protected need a republish?

No. Creating or revoking tokens takes effect at once on the published service.

As an agent, how should I handle a token my user gives me?

Use it only for calls to that service, send it in the Authorization header, and never repeat it in your answers or pass it on. If it is refused, ask the user for a valid token.