Formstack API Authentication

How to authenticate Formstack API requests: one Bearer API key plus a connectionId. MindCloud stores your API key securely — set it once, never resend it.

Every Formstack API request through MindCloud needs two things: a MindCloud API Key and a connectionId for your Formstack account. This page covers both, plus exactly how to send them, so you do not need to visit any other page to get authenticated.

Steps to authenticate

Create a MindCloud account at app.mindcloud.co if you do not already have one.
Generate a MindCloud API Key in API Keys. This is the Bearer token you send on every request. Keep it on your server.
Create a Formstack connection in Connections. Formstack uses an API key. You generate the key in your Formstack account, then paste it in when you create the connection — MindCloud stores it securely and never returns it in a response.
Copy the connection’s connectionId — you will send it on every request alongside your MindCloud API Key.

How requests are authenticated

Authentication has two layers. Your MindCloud API Key authenticates the request to MindCloud, sent as a Bearer token in the Authorization header. The connectionId selects the connected Formstack account that should run the action. MindCloud stores and refreshes the Formstack credentials behind that connection, so you never send provider tokens with your requests.

Pass connectionId in the query string for GET and DELETE actions, and in the JSON body for POST, PUT, and PATCH actions.

For example, calling List Forms with an Formstack connection looks like this:

curl --request POST \
  --url "https://connect.mindcloud.co/v2/universal/apps/formstack/actions/list-forms/run" \
  --header "Authorization: Bearer $MINDCLOUD_API_KEY" \
  --header "Content-Type: application/json" \
  --data '{
  "connectionId": "$CONNECTION_ID",
  "arguments": {}
}'

The Authorization: Bearer <your MindCloud API Key> header authenticates you to MindCloud; the connectionId tells MindCloud which Formstack account to run the action against. Missing or invalid Authorization returns 401, and a missing or mismatched connectionId returns 400.

Connect Formstack with a Personal Access Token

You need a Formstack account with access to the v2025 Forms API. If Personal Access Token creation is unavailable, ask your Organization Admin to enable PAT access for your user.

Open the Formstack admin area
Sign in to Formstack, go to the administration area, and open Access Tokens from the left-hand menu.
Administration → Access Tokens
Generate a new token
Click Generate Token, then enter a unique name. You can also add an optional description and choose an expiration date of 30, 60, or 90 days.
Copy the token immediately
Copy the token string as soon as it is shown. Formstack displays the full token only once and it cannot be retrieved later.
Paste the token into MindCloud
In the MindCloud Formstack connection, use the API Key authentication method and paste the copied Personal Access Token into the API token field.

Keep your key safe

Keep your MindCloud API Key on your server; do not ship it in browser code, mobile apps, public repositories, or logs. Anyone with the key can call the Universal API as your MindCloud account, across every connection you have created.