Connection types

Work out which of the seven connection types reaches a particular system, what each asks for, and what to do when a system fits none of them.

Skills for your coding agent

Connect a system for an agent

See it running: Trip planner

When you create a connection you pick what you're connecting to. The type decides what credential it asks for and how its operations are found.

The seven types#

Choose + New connection, then I will set it up, and the form asks What are you connecting to? with three of them: MCP server, HTTP API and AI model. To create one of the other four, choose Describe it to the builder and tell the Connection Builder what you need.

Type	What it reaches	What it asks for
HTTP API	Anything with an HTTP API	A token sent as `Authorization: Bearer <token>`, or for another header, an empty token and up to three header rows (name and value). The builder can also set up HTTP Basic auth, or none for a public API
MCP server	The tools a remote MCP server exposes	A token or headers, or Sign in in your browser if the server uses OAuth
AI model	One model, under limits an admin sets	Nothing. Mindset uses its own access to the model
Postgres database	A database, through queries you enable one at a time	A connection string
Google Sheet	One spreadsheet: read a range, append a row	A Google Cloud service account key
Knowledge base	A search server that holds your documents	Whatever an MCP server would: a token, headers or a browser sign-in. The server must speak MCP and expose exactly one tool, named `rag_search`
StackOne	HR, recruiting and CRM systems through StackOne	A sign-in to the system through StackOne's Hub, which keeps the credential

To connect any of them from your coding agent, see Connect a system.

What each one is for#

HTTP API is where most connections end up. The finance system in the invoice workflow is one. Its operations are set up one per method and path.

MCP server reaches things Mindset doesn't do itself: reading text from a scanned invoice, producing a spreadsheet, or a product whose vendor ships an MCP server. Each tool becomes an operation, and from then on it behaves like any other operation.

AI model is how functions and scripts call a model. An admin picks one model and sets a Size cap (maximum output tokens per call) and PII protection, which is on by default. A function step or a script phase names a model connection, not a model, so it can't pick a different model than the one it was given. The PII protection switch only matters while your org's personal data setting is on. See Audit and personal data.

Postgres database is for lookups and joins over more data than a sheet holds: supplier payment terms and two years of invoice history.

Google Sheet is for small tables a person also maintains by hand: who approves supplier queries, or how much variance each supplier is allowed.

Knowledge base grounds judgment in your own material. In the invoice workflow, the Assess phase searches the supplier contracts for the clause covering a price difference. Mindset doesn't load or index documents itself.

StackOne reaches HR, recruiting and CRM systems through one account linked in StackOne's Hub. StackOne holds that account's credential, and Mindset stores only which account it is.

The Slack app#

A Slack connection is an HTTP API connection on the Slack app adapter. It lets a script post a decision to Slack with buttons and receive the click back, through an $ask step. Create it with the Connection Builder, which asks for three values from a Slack app you create in your own workspace: the bot token, the signing secret and the app ID. The connection's Settings tab then shows Let a person answer in Slack, with the app manifest and the Request URL to copy into Slack.

For the setup step by step, see Post to Slack or send email.

How credentials are handled#

Whatever the type, Mindset holds the credential and adds it to each call, and it never reaches the agent or the model. How that's enforced is on Security and approval.

When the system you need isn't listed#

Ask three questions, in this order:

Does it have an API? Most systems do, including many whose vendor sells an integration and never mentions the API underneath. If it has one, use HTTP API.
Is there a remote MCP server for it? Vendors and communities publish them for many products. A server someone on your team runs on their own laptop can't be connected. It needs a remote address.
Is it only reachable by logging into a website and clicking through its screens? Then Mindset can't reach it. There is no type that drives a browser. Ask the vendor whether there's an API behind those screens. There usually is.

Before an agent can call an operation#

The connection must be live, and the operation enabled, available to agents, approved if it writes, and assigned in the agent's active version. See Connections and operations.

Limits#

An HTTP API that needs OAuth can't be connected yet. Use an API key or header auth. MCP servers support OAuth sign-in, shared by everyone using the connection.
Only remote MCP servers can be connected. A local (stdio) server can't.
An AI model connection has no cost cap or data residency control that Mindset enforces. The size cap and PII protection are the limits it applies.
A knowledge base can't be filled from Mindset. Its documents live on the search server.

You're done when#

You know which type each system in your workflow uses.
You have a credential for each one, scoped to what its operations need and pointed at the right account.
For anything that didn't fit, you know whether it has an API or a remote MCP server, or that it has neither.