tool-creation-patterns

Choose an MCP tool pattern by evaluating your compile-time knowledge and runtime needs. Use function macros for stateless utilities, derive macros for stateful tools, and ToolBuilder for dynamic runtime definitions.

The difference between function macro, derive macro, and ToolBuilder patterns is their flexibility level. Function macros handle simple stateless utilities, derive macros support stateful tools with session context, and ToolBuilder enables dynamic runtime tool definitions.

Register a stateful MCP tool needing per-session state using the derive macro pattern. It supports session access and per-tool task settings, maintaining context across interactions within the Turul MCP Framework.

Yes, you can use OnceLock for shared state across MCP tool patterns. The guidance covers shared-state considerations using OnceLock, ensuring safe concurrent access across utilities and stateful tools in the Turul MCP Framework.

Use the ToolBuilder pattern instead of macros when you need dynamic runtime tool definitions. ToolBuilder suits complex scenarios where tool structure is not fully known at compile time, unlike function and derive macros.

Yes, the Turul MCP Framework supports both stateless utilities and complex stateful tools. Pattern guidance applies across simple stateless functions and complex tools requiring session context or shared state via OnceLock.