Model Context Protocol in ElasticMS Admin
ElasticMS Admin exposes a Model Context Protocol (MCP) server at POST /api/mcp.
The endpoint lets MCP clients discover and use ElasticMS capabilities with the permissions of the authenticated API user. ElasticMS provides built-in tools and resources, and can also expose project-specific MCP tools, prompts, and resources configured in the CMS.
MCP concepts
ElasticMS uses three MCP concepts for custom CMS integrations:
| Concept | Use it for | ElasticMS entity |
|---|---|---|
| Tool | An action the model can call with arguments, such as searching content or creating a draft. | McpTool |
| Prompt | A reusable instruction or workflow the model can load with arguments, such as drafting a localized news article. | McpPrompt |
| Resource | Reference material the model can read, such as guidelines, documentation, prompt instructions, or reusable Markdown content. | McpResource |
Use a tool when the model must execute logic with input parameters. Use a prompt when the model needs a reusable task instruction. Use a resource when the model needs contextual information it can read by URI.
Admin configuration
The admin sidebar contains an MCP section with:
- MCP tools for custom callable tools.
- MCP prompts for custom reusable prompt workflows.
- MCP resources for custom readable resources.
Both are regular ElasticMS admin entities. They can be exported to JSON, versioned in Git, and imported across environments.
Recommended project structure
Keep exported CMS definitions under configs/admin, and keep the rendered Twig templates in the project skeleton:
demo/configs/admin/mcp-tool/
demo/configs/admin/mcp-prompt/
demo/configs/admin/mcp-resource/
demo/skeleton/template_ems/mcp/tools/
demo/skeleton/template_ems/mcp/prompts/
demo/skeleton/template_ems/mcp/resources/This keeps the CMS entity small while the actual response logic remains readable and testable in Twig files.
Pages
For low-level endpoint usage and curl examples, see the MCP API.