mcp4k-runtime/sh.ondr.mcp4k.runtime/Server/Builder

Builder

Builder for constructing a Server instance.

All configuration is done via fluent API calls, and once build is called, you get a fully configured Server ready to be started with Server.start.

Example:

val server = Server.Builder()
    .withPageSize(25)
    .withPrompt(::myPromptFunction)
    .withResourceProvider(myLocalFileProvider)
    .withServerInfo("MyServer", "1.0.0")
    .withTool(::myToolFunction)
    .withTransport(myTransport)
    .withTransportLogger(
      logIncoming = { msg -> println("SERVER INCOMING: $msg") },
      logOutgoing = { msg -> println("SERVER OUTGOING: $msg") },
    )
    .build()

server.start()

Constructors

constructor()

Functions

fun build(): Server

Builds the Server instance.

fun withContext(context: ServerContext): Server.Builder

fun withDispatcher(dispatcher: CoroutineContext): Server.Builder

Sets the coroutine context (or dispatcher) for the server's internal coroutines. Defaults to Dispatchers.Default if not set.

fun withPageSize(pageSize: Int): Server.Builder

Sets the default page size for paginated responses. Defaults to 20.

fun withPrompt(promptFunction: KFunction<*>): Server.Builder

Registers a prompt by referencing its @McpPrompt-annotated function.

fun withPrompts(vararg promptFunctions: KFunction<*>): Server.Builder

Registers multiple prompts by referencing their @McpPrompt-annotated functions.

withResourceProvider

fun withResourceProvider(provider: ResourceProvider): Server.Builder

Registers a resource provider that can list/read resources.

fun withServerInfo(name: String, version: String): Server.Builder

Sets the server's name and version, reported in the initialize response. Defaults to "MyServer" and "1.0.0" if not provided.

fun withTool(toolFunction: KFunction<*>): Server.Builder

Registers a tool by referencing its @McpTool-annotated function.

fun withTools(vararg toolFunctions: KFunction<*>): Server.Builder

Registers multiple tools by referencing their @McpTool-annotated functions.

fun withTransport(transport: Transport): Server.Builder

Sets the Transport used by the server to communicate with clients. This must be called before build, or an error is thrown.

withTransportLogger

fun withTransportLogger(logIncoming: suspend (String) -> Unit = {}, logOutgoing: suspend (String) -> Unit = {}): Server.Builder

Sets separate loggers for incoming and outgoing transport messages.