Downgrade MCP version to 0.9 (#3821) (#3823)

Author: opensearch-trigger-bot[bot]

ml-algorithms/build.gradle

@@ -85,8 +85,7 @@ dependencies {
     implementation('net.minidev:json-smart:2.5.2')
     implementation group: 'org.json', name: 'json', version: '20231013'
     implementation group: 'software.amazon.awssdk', name: 'netty-nio-client', version: "2.30.18"
-    // TODO: Replace the custom jar with dependency implementation 'io.modelcontextprotocol.sdk:mcp:0.10.0' after its release
-    api files('libs/mcp-0.10.0-SNAPSHOT.jar')
+    api('io.modelcontextprotocol.sdk:mcp:0.9.0')
     testImplementation("com.fasterxml.jackson.core:jackson-annotations:${versions.jackson}")
     testImplementation("com.fasterxml.jackson.core:jackson-databind:${versions.jackson_databind}")
     testImplementation group: 'com.networknt' , name: 'json-schema-validator', version: '1.4.0'

ml-algorithms/src/main/java/org/opensearch/ml/engine/algorithms/remote/McpConnectorExecutor.java

@@ -82,8 +82,6 @@ public List<MLToolSpec> getMcpToolSpecs() {
             Duration readTimeout = Duration.ofSeconds(super.getConnectorClientConfig().getReadTimeout());
 
             Consumer<HttpRequest.Builder> headerConfig = builder -> {
-                builder.header("Content-Type", "application/json");
-
                 for (Map.Entry<String, String> entry : connector.getDecryptedHeaders().entrySet()) {
                     builder.header(entry.getKey(), entry.getValue());
                 }

plugin/build.gradle

@@ -436,6 +436,7 @@ configurations.all {
     resolutionStrategy.force "jakarta.json:jakarta.json-api:2.1.3"
     resolutionStrategy.force "org.opensearch:opensearch:${opensearch_version}"
     resolutionStrategy.force "org.bouncycastle:bcprov-jdk18on:1.78.1"
+    resolutionStrategy.force 'io.projectreactor:reactor-core:3.7.0'
 }
 
 apply plugin: 'com.netflix.nebula.ospackage'