If you want an AI assistant to work on your WordPress site, you will soon encounter two terms: MCP and REST API. Both can provide a connection between the assistant and the website. The difference is how the assistant discovers and uses the operations available to it.
This applies whether you use Claude, Codex, Cursor or another agent. Start with two questions: which connection methods does your AI app support, and what actions does your WordPress site make available?
Delta’s Connections panel is a useful example because it offers both MCP and API modes.
What does an MCP connection mean?
MCP stands for Model Context Protocol. It gives compatible AI applications a standard way to discover and use tools supplied by another application.
For WordPress, those tools might read content, create a page, edit a template or retrieve design context. The agent can learn what a tool does and which information it expects, then call it when needed. The MCP documentation describes this tool-discovery and execution model.
Connecting an MCP server does not mean the AI gains every possible WordPress capability. The server determines which tools it exposes. Your account permissions and the site’s configuration determine what those tools are allowed to do.
For example, you might ask the agent to update the introduction on your About page. Through MCP, it uses the tools supplied by the site to find the page and make the supported change.
What does a REST API connection mean?
A REST API lets software communicate with your site through web requests. A request can retrieve information or perform an operation, with the response usually returned as structured data.
WordPress already has a REST API. It provides routes for resources such as posts, pages and media, and themes and plugins can add their own. WordPress’s REST API handbook explains the interface.
An agent can use an API when it has the relevant instructions and a way to make requests. Those instructions might come from documentation, a skill or an existing integration.
The same About-page change could happen through API requests: retrieve the page, update the introduction and save it. The agent needs to know which requests to send, what information to include and how to authenticate.
A REST API can also provide information about its available operations. MCP’s distinction is that it standardises tool discovery and calls for compatible AI clients.
How Delta makes the difference visible
In Delta → Connect, you can choose MCP or API. These are two routes to Delta’s underlying abilities: the supported actions the agent can perform on the site.
In MCP mode, a compatible client connects to Delta’s MCP server. The connection exposes tools for finding abilities, inspecting their requirements and running them.
In API mode, the agent uses Delta’s dedicated agent REST interface. This is a theme-provided interface, separate from WordPress’s standard routes for posts and pages. It exposes the same underlying ability system through direct requests.
For example, a page-editing action available through both routes can make the same change. What it can do still depends on your permissions and the actions enabled on the site.
How other WordPress integrations connect
Many integrations use MCP, but their setup differs. These documented examples show the main approaches:
| Integration | Connection approach |
|---|---|
| Ollie and Bricks | MCP through WordPress’s MCP Adapter, with Application Passwords and generated client configuration. |
| Elementor | Its own MCP integration for supported Elementor structures. |
| Easy MCP AI | MCP server inside WordPress, with OAuth; no separate service relays the connection. |
| WPVibe | A hosted MCP service: sign in, then authorize the WordPress site. |
| Novamira | MCP using the bundled WordPress MCP Adapter; intended for development and staging. |
| Etch Connector | A different approach: connects a coding agent to an open builder tab through Etch’s public API. |
| Delta | Native MCP or a dedicated agent REST API, accessing the same supported site actions. |
MCP fits a client’s tool interface; direct API access can fit scripts and coding agents. These examples describe their documented agent connections, rather than every API each product may provide.
Connection and access are separate
Adding a server address or API URL is only part of connecting. The site must also identify the caller and allow the requested operation.
Delta’s native MCP supports OAuth and WordPress Application Passwords. Its agent API uses its own access tokens. These credentials belong to different connection methods and should be configured using the corresponding instructions.
The assistant must also be able to reach the website. A site available only on your computer needs a connection that can reach that local environment. A cloud-hosted connector does not automatically have access to it.
What this means for your website
Start with the connection your AI app supports. MCP gives compatible assistants a standard tool interface; direct API access can suit a script or coding workflow. With either route, check that the agent can reach the site and perform the action you need, such as updating your About page. In Delta, both routes give access to the same supported site actions.
