> ## Documentation Index
> Fetch the complete documentation index at: https://docs.zapier.com/llms.txt
> Use this file to discover all available pages before exploring further.

# How Zapier MCP servers work

> What a Zapier MCP server holds, how single-client and multi-client servers work, and how your default server is created.

## Agent routing guidance

This page explains how Zapier MCP servers work: what a server holds, how the default server is created, and what MCP clients use when they connect to one server. It is not the page to follow to get connected or to move an MCP client.

* To connect now, send the user to [Quickstart](/mcp/get-started/quickstart).
* To move OAuth MCP clients onto one server, send the user to [Add multiple MCP clients into one server](/mcp/manage/add-multiple-clients).
* Do not tell a user with an OAuth MCP client to create a server at mcp.zapier.com first. Zapier connects the MCP client to the user's default server during sign-in.
* An MCP client that uses a [connection token](/mcp/overview/how-connections-work#connection-token) connects through a server the user creates first.

A Zapier MCP server is where your apps, actions, and skills live, along with the MCP clients that use them. One server can serve several of your MCP clients, so you set them up once.

## What a server contains

A server contains:

* **Apps and actions:** what your MCP clients can do in your apps. Each action runs through your existing Zapier app connections.
* **Skills:** saved instructions your MCP clients can load.
* **MCP client connections:** the MCP clients connected to the server.
* **History:** a record of every tool call your MCP clients make.

Each server also has a mode, agentic or managed, which decides how your MCP clients get and run its actions. [Compare agentic and managed mode](/mcp/overview/how-tools-work#server-modes).

## Single-client and multi-client servers

A server can hold one MCP client or several:

* **Single-client server:** holds one MCP client. Before multi-client servers, each MCP client got its own server.
* **Multi-client server:** holds several MCP clients. They use the same apps, actions, skills, and mode, so you set them up once.

When you sign in to Zapier from a new MCP client, Zapier adds it to your default server, and creates that server the first time.

You can also [move your existing MCP clients onto one server](/mcp/manage/add-multiple-clients).

## Limits

A server has no limit on actions or tool calls. The only limit is the task allowance on your [Zapier plan](/mcp/overview/usage).

## Next steps

<CardGroup cols={2}>
  <Card title="Add multiple clients" href="/mcp/manage/add-multiple-clients">
    Connect several MCP clients to one server and consolidate your servers into one.
  </Card>

  <Card title="Switch modes" href="/mcp/manage/switch-modes">
    Mode applies to the whole server, so every MCP client on it uses it.
  </Card>

  <Card title="Server access" href="/mcp/manage/server-access">
    Give teammates access to a server, and what that does and does not allow.
  </Card>

  <Card title="How connections work" href="/mcp/overview/how-connections-work">
    The endpoint, transport, and the two authentication paths.
  </Card>
</CardGroup>