Add Kotlin Weather STDIO server sample (#50)

* Add Kotlin Weather STDIO server sample

* Update gradle build command in Readme to exclude tests

samples/weather-stdio-server/.gitignore

@@ -0,0 +1,42 @@
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### IntelliJ IDEA ###
+.idea/
+*.iws
+*.iml
+*.ipr
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### Kotlin ###
+.kotlin
+
+### Eclipse ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
+
+### Mac OS ###
+.DS_Store

samples/weather-stdio-server/README.md

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+# Kotlin MCP Weather STDIO Server
+
+This project demonstrates how to build a Model Context Protocol (MCP) server in Kotlin that provides weather-related
+tools by consuming the National Weather Service (weather.gov) API. The server uses STDIO as the transport layer and
+leverages the Kotlin MCP SDK to expose weather forecast and alert tools.
+
+For more information about the MCP SDK and protocol, please refer to
+the [MCP documentation](https://modelcontextprotocol.io/introduction).
+
+## Prerequisites
+
+- Java 17 or later
+- Gradle (or the Gradle wrapper provided with the project)
+- Basic understanding of MCP concepts
+- Basic understanding of Kotlin and Kotlin ecosystems (sush as kotlinx-serialization, coroutines, ktor)
+
+## MCP Weather Server
+
+The project provides:
+
+- A lightweight MCP server built with Kotlin.
+- STDIO transport layer implementation for server-client communication.
+- Two weather tools:
+    - **Weather Forecast Tool** — returns details such as temperature, wind information, and a detailed forecast for a
+      given latitude/longitude.
+    - **Weather Alerts Tool** — returns active weather alerts for a given US state.
+
+## Building and running
+
+Use the Gradle wrapper to build the application. In a terminal run:
+
+```shell
+./gradlew clean build -x test
+```
+
+To run the server:
+
+```shell
+java -jar build/libs/<your-jar-name>.jar
+```
+
+> [!NOTE]
+> The server uses STDIO transport, so it is typically launched in an environment where the client connects via standard
+> input/output.
+
+## Tool Implementation
+
+The project registers two MCP tools using the Kotlin MCP SDK. Below is an overview of the core tool implementations:
+
+### 1. Weather Forecast Tool
+
+This tool fetches the weather forecast for a specific latitude and longitude using the `weather.gov` API.
+
+Example tool registration in Kotlin:
+
+```kotlin
+server.addTool(
+    name = "get_forecast",
+    description = """
+            Get weather forecast for a specific latitude/longitude
+        """.trimIndent(),
+    inputSchema = Tool.Input(
+        properties = JsonObject(
+            mapOf(
+                "latitude" to JsonObject(mapOf("type" to JsonPrimitive("number"))),
+                "longitude" to JsonObject(mapOf("type" to JsonPrimitive("number"))),
+            )
+        ),
+        required = listOf("latitude", "longitude")
+    )
+) { request ->
+    // Implementation tool
+}
+```
+
+### 2. Weather Alerts Tool
+
+This tool retrieves active weather alerts for a US state.
+
+Example tool registration in Kotlin:
+
+```kotlin
+server.addTool(
+    name = "get_alerts",
+    description = """
+        Get weather alerts for a US state. Input is Two-letter US state code (e.g. CA, NY)
+    """.trimIndent(),
+    inputSchema = Tool.Input(
+        properties = JsonObject(
+            mapOf(
+                "state" to JsonObject(
+                    mapOf(
+                        "type" to JsonPrimitive("string"),
+                        "description" to JsonPrimitive("Two-letter US state code (e.g. CA, NY)")
+                    )
+                ),
+            )
+        ),
+        required = listOf("state")
+    )
+) { request ->
+    // Implementation tool
+}
+```
+
+## Client Integration
+
+### Kotlin Client Example
+
+Since the server uses STDIO for transport, the client typically connects via standard input/output streams. A sample
+client implementation can be found in the tests, demonstrating how to send tool requests and process responses.
+
+### Claude for Desktop
+
+To integrate with Claude Desktop, add the following configuration to your Claude Desktop settings:
+
+```json
+{
+  "mcpServers": {
+    "weather": {
+      "command": "java",
+      "args": [
+        "-jar",
+        "/absolute/path/to/<your-jar-name>.jar"
+      ]
+    }
+  }
+}
+```
+
+> [!NOTE]
+> Replace `/absolute/path/to/<your-jar-name>.jar` with the actual absolute path to your built jar file.
+
+## Additional Resources
+
+- [MCP Specification](https://spec.modelcontextprotocol.io/)
+- [Kotlin MCP SDK](https://github.com/modelcontextprotocol/kotlin-sdk)
+- [Ktor Client Documentation](https://ktor.io/docs/welcome.html)
+- [Kotlinx Serialization](https://kotlinlang.org/docs/serialization.html)
+

samples/weather-stdio-server/build.gradle.kts

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+plugins {
+    kotlin("jvm") version "2.1.10"
+    kotlin("plugin.serialization") version "2.1.10"
+    id("com.github.johnrengelman.shadow") version "8.1.1"
+    application
+}
+
+application {
+    mainClass.set("io.modelcontextprotocol.sample.server.MainKt")
+}
+
+
+group = "org.example"
+version = "0.1.0"
+
+val mcpVersion = "0.3.0"
+val slf4jVersion = "2.0.9"
+val ktorVersion = "3.1.1"
+
+dependencies {
+    implementation("io.modelcontextprotocol:kotlin-sdk:$mcpVersion")
+    implementation("org.slf4j:slf4j-nop:$slf4jVersion")
+    implementation("io.ktor:ktor-client-content-negotiation:$ktorVersion")
+    implementation("io.ktor:ktor-serialization-kotlinx-json:$ktorVersion")
+    testImplementation(kotlin("test"))
+    testImplementation("org.jetbrains.kotlinx:kotlinx-coroutines-test:1.10.1")
+}
+
+tasks.test {
+    useJUnitPlatform()
+}
+
+kotlin {
+    jvmToolchain(17)
+}

samples/weather-stdio-server/gradle.properties

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+kotlin.code.style=official

samples/weather-stdio-server/gradle/wrapper/gradle-wrapper.properties

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+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.13-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

samples/weather-stdio-server/gradlew

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+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/HEAD/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+# This is normally unused
+# shellcheck disable=SC2034
+APP_BASE_NAME=${0##*/}
+# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
+APP_HOME=$( cd -P "${APP_HOME:-./}" > /dev/null && printf '%s\n' "$PWD" ) || exit
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    if ! command -v java >/dev/null 2>&1
+    then
+        die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Collect all arguments for the java command:
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
+#     and any embedded shellness will be escaped.
+#   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
+#     treated as '${Hostname}' itself on the command line.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"

samples/weather-stdio-server/gradlew.bat

@@ -0,0 +1,94 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+@rem SPDX-License-Identifier: Apache-2.0
+@rem
+
+@if "%DEBUG%"=="" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%"=="" set DIRNAME=.
+@rem This is normally unused
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if %ERRORLEVEL% equ 0 goto execute
+
+echo. 1>&2
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo. 1>&2
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if %ERRORLEVEL% equ 0 goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

samples/weather-stdio-server/settings.gradle.kts

@@ -0,0 +1,11 @@
+rootProject.name = "weather-stdio-server"
+
+plugins {
+    id("org.gradle.toolchains.foojay-resolver-convention") version "0.8.0"
+}
+
+dependencyResolutionManagement {
+    repositories {
+        mavenCentral()
+    }
+}

samples/weather-stdio-server/src/main/kotlin/io/modelcontextprotocol/sample/server/McpWeatherServer.kt

@@ -0,0 +1,132 @@
+package io.modelcontextprotocol.sample.server
+
+import io.ktor.client.*
+import io.ktor.client.plugins.*
+import io.ktor.client.plugins.contentnegotiation.*
+import io.ktor.http.*
+import io.ktor.serialization.kotlinx.json.*
+import io.ktor.utils.io.streams.*
+import io.modelcontextprotocol.kotlin.sdk.*
+import io.modelcontextprotocol.kotlin.sdk.server.Server
+import io.modelcontextprotocol.kotlin.sdk.server.ServerOptions
+import io.modelcontextprotocol.kotlin.sdk.server.StdioServerTransport
+import kotlinx.coroutines.CompletableDeferred
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.runBlocking
+import kotlinx.io.asSink
+import kotlinx.io.buffered
+import kotlinx.serialization.json.*
+
+// Main function to run the MCP server
+fun `run mcp server`() {
+    val def = CompletableDeferred<Unit>()
+
+    // Base URL for the Weather API
+    val baseUrl = "https://api.weather.gov"
+
+    // Create an HTTP client with a default request configuration and JSON content negotiation
+    val httpClient = HttpClient {
+        defaultRequest {
+            url(baseUrl)
+            headers {
+                append("Accept", "application/geo+json")
+                append("User-Agent", "WeatherApiClient/1.0")
+            }
+            contentType(ContentType.Application.Json)
+        }
+        // Install content negotiation plugin for JSON serialization/deserialization
+        install(ContentNegotiation) {
+            json(Json {
+                ignoreUnknownKeys = true
+                prettyPrint = true
+            })
+        }
+    }
+
+    // Create the MCP Server instance with a basic implementation
+    val server = Server(
+        Implementation(
+            name = "weather", // Tool name is "weather"
+            version = "1.0.0" // Version of the implementation
+        ),
+        ServerOptions(
+            capabilities = ServerCapabilities(tools = ServerCapabilities.Tools(listChanged = true))
+        )
+    ) { def.complete(Unit) }
+
+    // Register a tool to fetch weather alerts by state
+    server.addTool(
+        name = "get_alerts",
+        description = """
+            Get weather alerts for a US state. Input is Two-letter US state code (e.g. CA, NY)
+        """.trimIndent(),
+        inputSchema = Tool.Input(
+            properties = JsonObject(
+                mapOf(
+                    "state" to JsonObject(
+                        mapOf(
+                            "type" to JsonPrimitive("string"),
+                            "description" to JsonPrimitive("Two-letter US state code (e.g. CA, NY)")
+                        )
+                    ),
+                )
+            ),
+            required = listOf("state")
+        )
+    ) { request ->
+        val state = request.arguments["state"]?.jsonPrimitive?.content
+        if (state == null) {
+            return@addTool CallToolResult(
+                content = listOf(TextContent("The 'state' parameter is required."))
+            )
+        }
+
+        val alerts = httpClient.getAlerts(state)
+
+        CallToolResult(content = alerts.map { TextContent(it) })
+    }
+
+    // Register a tool to fetch weather forecast by latitude and longitude
+    server.addTool(
+        name = "get_forecast",
+        description = """
+            Get weather forecast for a specific latitude/longitude
+        """.trimIndent(),
+        inputSchema = Tool.Input(
+            properties = JsonObject(
+                mapOf(
+                    "latitude" to JsonObject(mapOf("type" to JsonPrimitive("number"))),
+                    "longitude" to JsonObject(mapOf("type" to JsonPrimitive("number"))),
+                )
+            ),
+            required = listOf("latitude", "longitude")
+        )
+    ) { request ->
+        val latitude = request.arguments["latitude"]?.jsonPrimitive?.doubleOrNull
+        val longitude = request.arguments["longitude"]?.jsonPrimitive?.doubleOrNull
+        if (latitude == null || longitude == null) {
+            return@addTool CallToolResult(
+                content = listOf(TextContent("The 'latitude' and 'longitude' parameters are required."))
+            )
+        }
+
+        val forecast = httpClient.getForecast(latitude, longitude)
+
+        CallToolResult(content = forecast.map { TextContent(it) })
+    }
+
+    // Create a transport using standard IO for server communication
+    val transport = StdioServerTransport(
+        System.`in`.asInput(),
+        System.out.asSink().buffered()
+    )
+
+    runBlocking {
+        server.connect(transport)
+        val done = Job()
+        server.onCloseCallback = {
+            done.complete()
+        }
+        done.join()
+    }
+}

samples/weather-stdio-server/src/main/kotlin/io/modelcontextprotocol/sample/server/WeatherApi.kt

@@ -0,0 +1,91 @@
+package io.modelcontextprotocol.sample.server
+
+import io.ktor.client.HttpClient
+import io.ktor.client.call.body
+import io.ktor.client.request.get
+import kotlinx.serialization.Serializable
+import kotlinx.serialization.json.JsonObject
+
+// Extension function to fetch forecast information for given latitude and longitude
+suspend fun HttpClient.getForecast(latitude: Double, longitude: Double): List<String> {
+    // Build the URI using provided latitude and longitude
+    val uri = "/points/$latitude,$longitude"
+    // Request the points data from the API
+    val points = this.get(uri).body<Points>()
+
+    // Request the forecast using the URL provided in the points response
+    val forecast = this.get(points.properties.forecast).body<Forecast>()
+
+    // Map each forecast period to a formatted string
+    return forecast.properties.periods.map { period ->
+        """
+            ${period.name}:
+            Temperature: ${period.temperature} ${period.temperatureUnit}
+            Wind: ${period.windSpeed} ${period.windDirection}
+            Forecast: ${period.detailedForecast}
+        """.trimIndent()
+    }
+}
+
+// Extension function to fetch weather alerts for a given state
+suspend fun HttpClient.getAlerts(state: String): List<String> {
+    // Build the URI using the given state code
+    val uri = "/alerts/active/area/$state"
+    // Request the alerts data from the API
+    val alerts = this.get(uri).body<Alert>()
+
+    // Map each alert feature to a formatted string
+    return alerts.features.map { feature ->
+        """
+            Event: ${feature.properties.event}
+            Area: ${feature.properties.areaDesc}
+            Severity: ${feature.properties.severity}
+            Description: ${feature.properties.description}
+            Instruction: ${feature.properties.instruction}
+        """.trimIndent()
+    }
+}
+
+// Data class representing the points response from the API
+@Serializable
+data class Points(
+    val properties: Properties
+) {
+    @Serializable
+    data class Properties(val forecast: String)
+}
+
+// Data class representing the forecast response from the API
+@Serializable
+data class Forecast(
+    val properties: Properties
+) {
+    @Serializable
+    data class Properties(val periods: List<Period>)
+
+    @Serializable
+    data class Period(
+        val number: Int, val name: String, val startTime: String, val endTime: String,
+        val isDaytime: Boolean, val temperature: Int, val temperatureUnit: String,
+        val temperatureTrend: String, val probabilityOfPrecipitation: JsonObject,
+        val windSpeed: String, val windDirection: String,
+        val shortForecast: String, val detailedForecast: String,
+    )
+}
+
+// Data class representing the alerts response from the API
+@Serializable
+data class Alert(
+    val features: List<Feature>
+) {
+    @Serializable
+    data class Feature(
+        val properties: Properties
+    )
+
+    @Serializable
+    data class Properties(
+        val event: String, val areaDesc: String, val severity: String,
+        val description: String, val instruction: String?,
+    )
+}

samples/weather-stdio-server/src/main/kotlin/io/modelcontextprotocol/sample/server/main.kt

@@ -0,0 +1,3 @@
+package io.modelcontextprotocol.sample.server
+
+fun main() = `run mcp server`()

samples/weather-stdio-server/src/test/kotlin/io/modelcontextprotocol/sample/client/ClientStdio.kt

@@ -0,0 +1,56 @@
+package io.modelcontextprotocol.sample.client
+
+import io.modelcontextprotocol.kotlin.sdk.CallToolRequest
+import io.modelcontextprotocol.kotlin.sdk.Implementation
+import io.modelcontextprotocol.kotlin.sdk.TextContent
+import io.modelcontextprotocol.kotlin.sdk.client.Client
+import io.modelcontextprotocol.kotlin.sdk.client.StdioClientTransport
+import kotlinx.coroutines.runBlocking
+import kotlinx.io.asSink
+import kotlinx.io.asSource
+import kotlinx.io.buffered
+import kotlinx.serialization.json.JsonObject
+import kotlinx.serialization.json.JsonPrimitive
+
+
+fun main(): Unit = runBlocking {
+    val process = ProcessBuilder("java", "-jar", "build/libs/weather-stdio-server-0.1.0-all.jar")
+        .start()
+
+    val transport = StdioClientTransport(
+        input = process.inputStream.asSource().buffered(),
+        output = process.outputStream.asSink().buffered()
+    )
+
+    // Initialize the MCP client with client information
+    val client = Client(
+        clientInfo = Implementation(name = "weather", version = "1.0.0"),
+    )
+
+    client.connect(transport)
+
+
+    val toolsList = client.listTools()?.tools?.map { it.name }
+    println("Available Tools = $toolsList")
+
+    val weatherForecastResult = client.callTool(
+        CallToolRequest(
+            name = "get_forecast",
+            arguments = JsonObject(mapOf("latitude" to JsonPrimitive(38.5816), "longitude" to JsonPrimitive(-121.4944)))
+        )
+    )?.content?.map { if (it is TextContent) it.text else it.toString() }
+
+    println("Weather Forcast: ${weatherForecastResult?.joinToString(separator = "\n", prefix = "\n", postfix = "\n")}")
+
+    val alertResult =
+        client.callTool(
+            CallToolRequest(
+                name = "get_alerts",
+                arguments = JsonObject(mapOf("state" to JsonPrimitive("TX")))
+            )
+        )?.content?.map { if (it is TextContent) it.text else it.toString() }
+
+    println("Alert Response = $alertResult")
+
+    client.close()
+}