SJS.Neos.MCP

Core MCP (Model Context Protocol) server implementation for Neos CMS 9.x.

Quick Start

Neos 9

Install these Feature Sets:

• Neos composer require sjs/neos-mcp-feature-set-neos 📦 Packagist

• ContentRepository composer require sjs/neos-mcp-feature-set-cr 📦 Packagist

• Resources composer require sjs/neos-mcp-feature-set-resources 📦 Packagist

For Testing:

• Test composer require sjs/neos-mcp-feature-set-test 📦 Packagist

Configuration

Server instances are defined in Configuration/Settings.Server.yaml:

SJS:
  Neos:
    MCP:
      server:
        mcp: # <-- This is the default for now
          featureSets:
            myFeatureSet: \Vendor\Site\MCP\FeatureSet\MyFeatureSet

Multiple named server instances can coexist alongside mcp.

Implementing new Features

Adding a new FeatureSet

1. Create a class extending AbstractFeatureSet with #[Flow\Scope("singleton")].

2. Implement initialize() to register tools via $this->addTool(...).

3. Optionally override resourcesList(), resourcesRead(), resourcesTemplatesList(), completionComplete().

4. Register the class in Configuration/Settings.Server.yaml under server.mcp.featureSets.

Tool name prefixes

AbstractFeatureSet automatically derives a prefix from the class name (e.g., WorkspaceFeatureSet → prefix workspace). Tool names are exposed as {prefix}_{tool_name}.

Development

MCP Inspector

yarn mcp-inspector-cli

Launches the MCP Inspector UI for interactive testing.

References

• Model Context Protocol

• MCP Inspector