Royal MCP next to other MCP servers
Many WordPress sites now run more than one MCP server. Elementor has one, the WordPress MCP Adapter adds another, and several SEO and AI plugins bundle their own. Royal MCP is built to sit beside all of them: its tools are available through the WordPress Abilities API to servers that use it, it signs AI clients in at its own address, and it tells you by name when another plugin is in the way. This guide explains how that works, which settings control it, and what to do when two plugins collide.
Three ways Royal MCP’s tools reach an AI client
| Route | Address | How the client signs in |
|---|---|---|
| Royal MCP’s own MCP server | /wp-json/royal-mcp/v1/mcp | OAuth (Claude, ChatGPT, Cursor and most clients) or the Royal MCP API key |
| The WordPress MCP Adapter, if installed | A separate server named Royal MCP at /wp-json/royal-mcp-server/v1/mcp | However the adapter signs clients in, usually a WordPress Application Password |
| The WordPress Abilities API | Abilities named royal-mcp/…, for example royal-mcp/wp-get-posts | Any WordPress REST sign-in, usually an Application Password; also browser agents using your login |
Whichever route a call takes, it runs the same Royal MCP tool, with the same permission checks, the same undo tokens and the same Activity Log entry. The routes are extra doors to the same room, not separate copies of Royal MCP.
Royal MCP on the WordPress Abilities API
WordPress 6.9 added the Abilities API, a shared list of actions that plugins offer to AI tools. On WordPress 6.9 or later, Royal MCP registers each of its tools there as an ability under the royal-mcp/ namespace, with a category, a description, read or write hints and the shape of its reply. MCP servers built on the Abilities API, and browser agents, can then find and call those abilities.
Royal MCP keeps its abilities off the WordPress MCP Adapter’s default server, so they do not crowd the tool list of every client that connects to it. Instead, when the adapter is installed, Royal MCP adds its own named server, called Royal MCP, to the adapter. Clients that want Royal MCP’s tools through the adapter connect to that server.
Who may use Royal MCP tools this way
Calls through the Abilities API, other MCP servers and browser agents follow these settings on Royal MCP > Settings:
- Who can use tools through other MCP servers and browser agents decides which users may use them at all. It is set to administrators by default.
- Access level: other MCP servers and browser agents sets these calls to Full, Read-only or Drafts only.
- Read-only mode and Drafts only apply on top, as they do everywhere.
These calls also count towards Royal MCP’s limit of 300 requests per minute per user, and the Application Passwords they use are listed under Royal MCP > Connected Clients. For details, read Who can connect AI clients and Application Password connections.
Turn it off
If you want each MCP server on the site to keep to its own tools, turn off Register tools with the WordPress Abilities API under Royal MCP > Settings > Advanced. Royal MCP’s tools then disappear from the Abilities API and the MCP Adapter, while Royal MCP’s own MCP server keeps working for clients connected to it directly. When Royal MCP itself is switched off, its abilities are not offered either.
Sharing the site’s sign-in addresses
An AI client learns how to sign in to a site by reading a few standard addresses, such as /.well-known/oauth-authorization-server, and then follows them to a sign-in page. Every MCP plugin with its own sign-in wants those addresses, and only one plugin can answer each one. When the wrong plugin answers, the AI client signs in to that plugin instead, or fails with errors such as ChatGPT’s “Unknown OAuth client.”
From version 1.5.12, Royal MCP avoids the contest:
- It signs AI clients in at its own address, under
/wp-json/royal-mcp/v1, which no other plugin answers. From 1.5.14, clients that connected earlier use it too, so existing connections keep working. - It answers its own sign-in documents first, before WordPress hands the request to other plugins, and only at its own exact addresses.
- It steps aside at the site root. When another plugin’s sign-in uses the site-root addresses, Royal MCP leaves those addresses to it. AI clients that follow Royal MCP’s own address still connect to Royal MCP, and clients that only read the site root get the other plugin, so both keep working. The Royal MCP screens show a notice naming the plugin that owns the site-root address.
To connect an AI client to Royal MCP on a site with several MCP plugins, always give it Royal MCP’s server address, https://your-site.com/wp-json/royal-mcp/v1/mcp, rather than the bare site address.
The sign-in self-check and the coexistence report
Royal MCP checks its own sign-in the way an AI client would: it follows the path from the first challenge to the sign-in server, including redirects and the www and non-www versions of your domain. If another plugin answers any step, a notice on the Royal MCP screens names that plugin (or the REST address it answers on), shows which step it answers, and gives the fix.
For the full picture, ask your AI client to run wp_get_mcp_coexistence. It reports the other MCP servers and hubs on the site (Elementor MCP and whether it is switched on, the WordPress MCP Adapter and which plugins carry a copy of it, Angie, and any other active MCP plugin), which plugin answers each shared address including the server card, llms.txt and robots.txt, which AI bots robots.txt blocks, whether Royal MCP’s tools can be reached through another server, and the sign-in path step by step. It is read-only, needs an administrator, and takes a few seconds because it loads each address from your site.
Common neighbours and what to expect
| Plugin | What happens | What to do |
|---|---|---|
| WordPress MCP Adapter | Royal MCP adds its own named server to the adapter, next to the adapter’s default server. | Nothing. If you do not want Royal MCP tools offered there, turn off Abilities API registration. |
| Two plugins that each bundle a copy of the MCP Adapter | Mixed versions of the adapter would be loaded at once, so Royal MCP keeps its adapter server off. Its own MCP server keeps working. | See When plugins bundle their own copy of the MCP Adapter below. |
| Elementor with its MCP server switched on | Both servers run side by side. Royal MCP shows a notice on its screens and points AI clients to Elementor’s own tools for building layouts, while its Elementor editing tools keep working. | Nothing. Connect each client to the server you want, or both. |
| Angie | Angie can refuse calls to other MCP Adapter servers until its consent setting allows them. When it does, Royal MCP’s message names that setting. | Allow the call in Angie’s settings, or connect to Royal MCP’s own server, which Angie does not affect. |
| Rank Math, and other plugins with the same bundled MCP sign-in | Their sign-in can answer the site-root addresses; ChatGPT then shows “Unknown OAuth client.” | See ChatGPT shows “Unknown OAuth client.” with Rank Math. |
| Other MCP plugins with their own OAuth sign-in | They may answer the site-root sign-in addresses. | Royal MCP steps aside at the site root and keeps its own address. If clients still reach the wrong sign-in, follow Another plugin is answering OAuth sign-in. |
The Works with other MCP plugins page lists more plugins we have tested next to Royal MCP.
When plugins bundle their own copy of the MCP Adapter
The WordPress MCP Adapter comes as a plugin of its own, but some versions of Rank Math and WooCommerce, and a few other plugins, include their own copy of it inside the plugin. A site that runs Rank Math, WooCommerce and the standalone MCP Adapter plugin can therefore carry three copies of the adapter, often at different versions. Most of the time you never notice. When the copies do not match, the adapter can break in ways that look like a Royal MCP problem but are not.
What you’ll notice
- An AI client that connects through the MCP Adapter no longer lists Royal MCP’s tools, or the Royal MCP server is missing from the adapter.
- The standalone MCP Adapter plugin, or another plugin’s adapter server, stops working too, even though it is up to date.
- The debug log fills with the same notices over and over, such as
WordPress ability 'mcp-adapter/discover-abilities' does not exist. - The coexistence report says the adapter’s classes were loaded from two or more copies and names them, for example standalone plugin, bundled in seo-by-rank-math.
Why it happens
PHP can load each part of the adapter only once per request. When several copies are installed, whichever copy loads a part first supplies it, so one request can end up with some parts from a newer copy and some from an older one. Parts that changed between versions no longer fit together, and the adapter stops registering its own tools or fails to start its servers. Which copy wins can depend on the order plugins load, so the problem can appear or disappear after an update or after activating another plugin.
What Royal MCP does about it
On every request, Royal MCP checks where the adapter’s parts were loaded from. When they come from more than one copy, it does not add its Royal MCP server to the adapter, so it does not add to the breakage. As soon as the parts come from a single copy again, Royal MCP adds its server back by itself; there is nothing to reset.
Royal MCP’s own MCP server, at /wp-json/royal-mcp/v1/mcp, does not use the adapter at all and keeps working throughout. To see which copies are loaded, ask your AI client to run wp_get_mcp_coexistence. The WordPress MCP Adapter line of the report names every copy and says that Royal MCP’s adapter server is off until one copy is left.
What you can do
- Update the plugins that bundle the adapter, and the standalone MCP Adapter plugin if you use it. Newer releases carry newer copies, and when the copies line up the conflict usually goes away. Run the coexistence report again afterwards to check.
- Keep only one copy active. If a plugin you need already bundles a newer copy of the adapter, deactivate the standalone MCP Adapter plugin. If the standalone plugin is the newer one and you do not need the plugin that bundles the older copy, deactivate that plugin instead.
- Connect AI clients to Royal MCP’s own address,
https://your-site.com/wp-json/royal-mcp/v1/mcp. It is not affected by the adapter, so clients connected there keep every Royal MCP tool whatever the adapter is doing.
The repeated mcp-adapter/… notices in the debug log are written by the adapter itself, not by Royal MCP, and they usually stop once a single copy of the adapter is loaded.
Troubleshooting
The AI client connects, but to another plugin’s server
The client was given the bare site address and followed another plugin’s sign-in. Remove the connector in the AI client and add it again with https://your-site.com/wp-json/royal-mcp/v1/mcp. Check that Royal MCP is 1.5.12 or later.
A Royal MCP notice says another plugin answers sign-in
Read the plugin name and the step in the notice, then apply the fix it shows. After changing the other plugin, use the notice’s Re-check now button, or reload the Royal MCP screen after a few minutes, to confirm.
Royal MCP’s server does not appear in the MCP Adapter
Check that the site runs WordPress 6.9 or later, that Royal MCP is switched on, that Register tools with the WordPress Abilities API is on, and that only one copy of the adapter is loaded (the coexistence report tells you; see When plugins bundle their own copy of the MCP Adapter).
Calls through another server say Royal MCP tools are “not available to your account”
The user is not covered by Who can use tools through other MCP servers and browser agents, which is set to administrators by default. Widen it, or use an administrator account.
Calls through another server can read but not change anything
Access level: other MCP servers and browser agents is set to Read-only or Drafts only, or a site-wide mode is on. The refusal message says which.
Frequently asked questions
Will Royal MCP break my other MCP plugin?
No. Royal MCP answers only its own addresses under /wp-json/royal-mcp/v1, leaves the site-root sign-in addresses to another plugin that uses them, and does not change other servers’ tools. Your AI clients can connect to both.
Do I need the WordPress MCP Adapter to use Royal MCP?
No. Royal MCP is a complete MCP server on its own. The adapter is only another way to reach its tools if you already use it.
Can I keep Royal MCP’s tools out of other MCP servers?
Yes. Turn off Register tools with the WordPress Abilities API under Royal MCP > Settings > Advanced. Royal MCP’s own server keeps working.
Do my access settings apply when tools are used through another server?
Yes. The setting Who can use tools through other MCP servers and browser agents, the access level for other routes, Read-only mode and Drafts only all apply, and every tool still checks the user’s WordPress permissions.
Royal MCP’s server is missing from the MCP Adapter and the debug log shows notices about mcp-adapter abilities. Why?
Some versions of Rank Math, WooCommerce and other plugins include their own copy of the WordPress MCP Adapter. When a site loads parts of more than one copy, the adapter runs with mixed versions, and Royal MCP keeps its adapter server off until a single copy is left. Royal MCP’s own address keeps working. Run wp_get_mcp_coexistence to see which plugins carry a copy, then update them or keep only one copy active.
Which version do I need?
Royal MCP 1.5.12 or later for its own sign-in address and the sign-in self-check, and 1.5.14 or later so clients connected before the update use it too. Abilities API registration needs WordPress 6.9 or later.