phpBB MCP Server

How it works

The extension adds one endpoint to your board, app.php/mcp. An AI app sends tool calls there with a member’s token. The board checks each call and runs it with phpBB’s own code.

An AI app calls the board’s MCP endpoint with a member’s token; the board checks the call and runs it through phpBB. AI app Claude, ChatGPT, Gemini, Cursor … HTTPS MCP endpoint token or OAuth sign-in identifies the member Six checks switches, permissions, scope, account state phpBB same code as the board’s own pages
Each tool call takes this path. Permissions are checked again on every call.

The six checks

A tool call only runs when all of these allow it:

  1. The board switch. The MCP server is off after installation. Moderation tools have a second switch, and permanent deletion and address bans each have their own.
  2. The MCP permission. The member needs Can use the MCP server, which nobody has after installation.
  3. The tool’s permission. Every tool except whoami needs a permission in the ACP category “MCP server” (closely related tools share one), so you can allow reading but not posting, or soft deleting but not banning.
  4. The token scope. The member picks scopes when creating a token or approving an app. Writing, sending private messages and moderation are never pre-selected; only reading (forums and private messages) is pre-selected when an app asks for it.
  5. phpBB’s own permission. The same check the website makes, such as f_read to read a forum or m_softdelete to soft delete a post, in that post’s forum.
  6. The account. Banned, inactive and bot accounts are refused, and changing the password ends every token and connected app.

Members, moderators and administrators

Members

Read forums, topics and posts, search, post and reply, edit their own posts, and read and send private messages. Moderator powers never apply here: a moderator posting through MCP is treated like any member.

Moderators

Review the queue, reports, post details and the moderator log; approve, soft delete, restore, lock, move and edit; warn, note, ban and purge spam accounts. Every change is a preview first and needs a confirmation.

Administrators

Turn the server and each feature on, set limits, grant permissions, manage OAuth apps and read the audit log in the ACP. A spam account queued for deletion can be reviewed there before it goes.

What leaves your board

The extension sends nothing on its own. Board content leaves the board only as the answer to a request a member makes with their own token or app, and only what that member may see. If the member uses a hosted AI app, those answers go to that AI provider. IP addresses are shown to moderators as pseudonymous handles unless you allow raw addresses for specific moderators. Mention AI apps in your board’s privacy policy.

Spam accounts

For accounts with up to 50 posts, the purge_spammer tool bans the account, revokes its tokens, soft deletes all its posts and closes the reports on them, in one step a moderator confirms. By default the account is then deleted after a grace period, with the evidence kept for administrators. Boards that prefer to keep spammers banned can choose that instead.