Struct McpServerBuilder 

pub struct McpServerBuilder { /* private fields */ }

Builder for McpServer — the main entry point for configuring your server.

Implementations

impl McpServerBuilder

pub fn new() -> Self

pub fn name(self, name: impl Into<String>) -> Self

Set the server name (shown to clients during handshake)

pub fn version(self, version: impl Into<String>) -> Self

Set the server version

pub fn instructions(self, instructions: impl Into<String>) -> Self

Human-readable instructions for how to use this server

pub fn auth(self, provider: DynAuthProvider) -> Self

Require authentication on all requests using the given provider.

Requests with no or invalid credentials receive HTTP 401 on SSE/HTTP transports. Stdio transport is unaffected (it relies on process-level access control).

Example

use mcp_kit::prelude::*;
use mcp_kit::auth::BearerTokenProvider;
use std::sync::Arc;

McpServer::builder()
    .name("my-server")
    .version("1.0")
    .auth(Arc::new(BearerTokenProvider::new(["secret"])))
    .build();

pub fn optional_auth(self, provider: DynAuthProvider) -> Self

Accept an auth provider but allow unauthenticated requests through.

Authenticated requests have an identity available via Auth; unauthenticated requests have no identity and may reach handlers with None.

pub fn tool<M>(self, tool: Tool, handler: impl ToolHandler<M>) -> Self

Register a tool with an explicit Tool descriptor and a handler function.

pub fn tool_def(self, def: ToolDef) -> Self

Register a tool using a pre-built ToolDef (from the #[tool] macro).

pub fn tool_fn<M>( self, name: impl Into<String>, description: impl Into<String>, handler: impl ToolHandler<M>, ) -> Self

Convenience: register a no-parameter tool.

pub fn resource<M>( self, resource: Resource, handler: impl ResourceHandler<M>, ) -> Self

Register a static resource (exact URI match).

pub fn resource_template<M>( self, template: ResourceTemplate, handler: impl ResourceHandler<M>, ) -> Self

Register a URI-template resource (e.g. "file://{path}").

pub fn resource_def(self, def: ResourceDef) -> Self

Register a resource using a pre-built ResourceDef (from the #[resource] macro).

pub fn prompt<M>(self, prompt: Prompt, handler: impl PromptHandler<M>) -> Self

Register a prompt template.

pub fn prompt_def(self, def: PromptDef) -> Self

Register a prompt using a pre-built PromptDef (from the #[prompt] macro).

pub fn completion<M>(self, handler: impl CompletionHandler<M>) -> Self

Register a global completion handler for auto-completing prompt/resource arguments.

This handler is called for any completion/complete request that doesn’t have a more specific handler (prompt-specific or resource-specific).

Example

use mcp_kit::prelude::*;
use mcp_kit::types::messages::{CompleteRequest, CompleteResult};

McpServer::builder()
    .name("my-server")
    .completion(|req: CompleteRequest| async move {
        // Auto-complete based on argument name
        let values = match req.argument.name.as_str() {
            "language" => vec!["rust", "python", "javascript"],
            _ => vec![],
        };
        Ok(CompleteResult::new(values))
    })
    .build();

pub fn resource_completion<M>( self, uri_pattern: impl Into<String>, handler: impl CompletionHandler<M>, ) -> Self

Register a completion handler for a specific resource URI pattern.

The pattern can be an exact URI or a template like "file://{path}".

pub fn prompt_with_completion<M1, M2>( self, prompt: Prompt, handler: impl PromptHandler<M1>, completion: impl CompletionHandler<M2>, ) -> Self

Register a prompt with an associated completion handler.

The completion handler provides auto-complete suggestions for the prompt’s arguments.

pub fn with_plugin_manager(self, plugin_manager: PluginManager) -> Self

Attach a plugin manager with pre-loaded plugins.

All tools, resources, and prompts from loaded plugins will be automatically registered with the server.

Example

use mcp_kit::prelude::*;
use mcp_kit::plugin::PluginManager;

let mut plugin_manager = PluginManager::new();
plugin_manager.load_from_path("./plugins/weather.so")?;

McpServer::builder()
    .name("my-server")
    .with_plugin_manager(plugin_manager)
    .build();

pub fn load_plugin(self, path: &str) -> McpResult<Self>

Load a plugin from a file path.

This is a convenience method that creates a PluginManager if needed and loads the plugin.

Example

use mcp_kit::prelude::*;

McpServer::builder()
    .name("my-server")
    .load_plugin("./plugins/weather.so")?
    .load_plugin("./plugins/database.so")?
    .build();

pub fn load_plugin_with_config( self, path: &str, config: PluginConfig, ) -> McpResult<Self>

Load a plugin with custom configuration.

pub fn build(self) -> McpServer

Trait Implementations

impl Default for McpServerBuilder

fn default() -> Self

Returns the “default value” for a type.