# Payload v4: the MCP plugin exposes your collections to LLMs — and it's opt-out

> Source: <https://dev.to/zawoj/payload-v4-the-mcp-plugin-exposes-your-collections-to-llms-and-its-opt-out-2nlg>
> Published: 2026-06-26 09:00:10+00:00

`@payloadcms/plugin-mcp`

turns your Payload CMS into an MCP server, exposing your collections as tools for LLMs.

Heads up for v4: after a refactor, every collection is now exposed with full CRUD **by default**. It's opt-out — you disable individual tools rather than enabling them:

```
mcpPlugin({
  collections: {
    // posts is exposed automatically — no entry needed
    users: { tools: { create: false, update: false, delete: false } }, // find only
  },
})
```

Custom tools are defined with the `defineTool`

builder, taking input via `zod`

v4:

```
tools: {
  getPostScores: defineTool({
    description: 'Score recent posts',
    input: z.object({ since: z.string() }),
  }).handler(async ({ input, req }) => ({ content: [/* ... */] })),
}
```

⚠️ The thing to actually do after upgrading: collections you never listed are suddenly reachable through MCP. Review them and disable anything sensitive — an exposed `users`

collection with `delete`

is not a great default to inherit by accident.