name: mcp-tool description: Create new MCP tools. Use when adding tools, creating MCP capabilities, extending server functionality, or adding new agent abilities. allowed-tools: Read, Glob, Grep, Edit, Write

Creating MCP Tools

MCP tools follow a two-layer pattern: pure Domain logic wrapped by an MCP server tool.

Steps

1. Domain Tool - Create in Domain/Tools/ with pure business logic
2. MCP Wrapper - Create in McpServer*/McpTools/ inheriting from Domain tool
3. Registration - Add to DI in the MCP server's Program.cs or module

Which MCP Server?

Templates

See domain-template.md for the Domain tool pattern. See mcp-template.md for the MCP wrapper pattern.

Checklist

• Domain tool has Name and Description constants
• Domain tool contains pure logic (no MCP dependencies)
• MCP wrapper uses [McpServerToolType] class attribute
• MCP wrapper uses [McpServerTool] and [Description] method attributes
• Error handling returns ToolResponse.Create(ex) on failure
• Logging includes tool name context
• CancellationToken passed through all async operations