Reduce logging levels

mcp-core/src/main/java/io/modelcontextprotocol/client/LifecycleInitializer.java

@@ -250,7 +250,6 @@ public McpSchema.InitializeResult currentInitializationResult() {
 	 * @param t The exception to handle
 	 */
 	public void handleException(Throwable t) {
-		logger.warn("Handling exception", t);
 		if (t instanceof McpTransportSessionNotFoundException) {
 			DefaultInitialization previous = this.initializationRef.getAndSet(null);
 			if (previous != null) {

mcp-core/src/main/java/io/modelcontextprotocol/client/McpAsyncClient.java

@@ -484,9 +484,7 @@ public Mono<Void> addRoot(Root root) {
 			if (this.isInitialized()) {
 				return this.rootsListChangedNotification();
 			}
-			else {
-				logger.warn("Client is not initialized, ignore sending a roots list changed notification");
-			}
+			logger.debug("Client is not initialized, ignore sending a roots list changed notification");
 		}
 		return Mono.empty();
 	}
@@ -514,10 +512,7 @@ public Mono<Void> removeRoot(String rootUri) {
 				if (this.isInitialized()) {
 					return this.rootsListChangedNotification();
 				}
-				else {
-					logger.warn("Client is not initialized, ignore sending a roots list changed notification");
-				}
-
+				logger.debug("Client is not initialized, ignore sending a roots list changed notification");
 			}
 			return Mono.empty();
 		}

mcp-core/src/main/java/io/modelcontextprotocol/client/transport/StdioClientTransport.java

@@ -10,10 +10,13 @@
 import java.nio.charset.StandardCharsets;
 import java.time.Duration;
 import java.util.ArrayList;
+import java.util.EnumSet;
 import java.util.List;
+import java.util.Set;
 import java.util.concurrent.Executors;
 import java.util.function.Consumer;
 import java.util.function.Function;
+import java.util.stream.IntStream;
 
 import io.modelcontextprotocol.json.TypeRef;
 import io.modelcontextprotocol.json.McpJsonMapper;
@@ -41,6 +44,15 @@ public class StdioClientTransport implements McpClientTransport {
 
 	private static final Logger logger = LoggerFactory.getLogger(StdioClientTransport.class);
 
+	// @formatter:off
+	private static final Set<Integer> EXIT_SUCCESS_CODES = Set.of(
+			0,   // success
+			130, // interrupted (SIGINT)
+			141, // pipeline shortcut (SIGPIPE)
+			143  // graceful termination (SIGTERM)
+	);
+	// @formatter:on
+
 	private final Sinks.Many<JSONRPCMessage> inboundSink;
 
 	private final Sinks.Many<JSONRPCMessage> outboundSink;
@@ -356,11 +368,12 @@ public Mono<Void> closeGracefully() {
 				return Mono.<Process>empty();
 			}
 		})).doOnNext(process -> {
-			if (process.exitValue() != 0) {
-				logger.warn("Process terminated with code {}", process.exitValue());
+			int exitValue = process.exitValue();
+			if (EXIT_SUCCESS_CODES.contains(exitValue)) {
+				logger.info("MCP server completed successfully with code {}", exitValue);
 			}
 			else {
-				logger.info("MCP server process stopped");
+				logger.warn("MCP server process failed with code {}", exitValue);
 			}
 		}).then(Mono.fromRunnable(() -> {
 			try {

mcp-core/src/main/java/io/modelcontextprotocol/server/McpAsyncServer.java

@@ -513,14 +513,13 @@ public Mono<Void> removeTool(String toolName) {
 
 		return Mono.defer(() -> {
 			if (this.tools.removeIf(toolSpecification -> toolSpecification.tool().name().equals(toolName))) {
-
 				logger.debug("Removed tool handler: {}", toolName);
 				if (this.serverCapabilities.tools().listChanged()) {
 					return notifyToolsListChanged();
 				}
 			}
 			else {
-				logger.warn("Ignore as a Tool with name '{}' not found", toolName);
+				logger.warn("Failed to remove tool with name '{}' (not found)", toolName);
 			}
 
 			return Mono.empty();
@@ -637,7 +636,7 @@ public Mono<Void> removeResource(String resourceUri) {
 				return Mono.empty();
 			}
 			else {
-				logger.warn("Ignore as a Resource with URI '{}' not found", resourceUri);
+				logger.warn("Failed to remove resource with URI '{}' (not found)", resourceUri);
 			}
 			return Mono.empty();
 		});
@@ -701,7 +700,7 @@ public Mono<Void> removeResourceTemplate(String uriTemplate) {
 				logger.debug("Removed resource template: {}", uriTemplate);
 			}
 			else {
-				logger.warn("Ignore as a Resource Template with URI '{}' not found", uriTemplate);
+				logger.warn("Failed to remove a resource template with URI '{}' (not found)", uriTemplate);
 			}
 			return Mono.empty();
 		});
@@ -907,7 +906,7 @@ public Mono<Void> removePrompt(String promptName) {
 				return Mono.empty();
 			}
 			else {
-				logger.warn("Ignore as a Prompt with name '{}' not found", promptName);
+				logger.warn("Failed to remove a prompt with name '{}' (not found)", promptName);
 			}
 			return Mono.empty();
 		});

mcp-core/src/main/java/io/modelcontextprotocol/server/McpStatelessAsyncServer.java

@@ -390,7 +390,7 @@ public Mono<Void> removeTool(String toolName) {
 				logger.debug("Removed tool handler: {}", toolName);
 			}
 			else {
-				logger.warn("Ignore as a Tool with name '{}' not found", toolName);
+				logger.warn("Failed to remove a tool with name '{}' (not found)", toolName);
 			}
 
 			return Mono.empty();
@@ -492,7 +492,7 @@ public Mono<Void> removeResource(String resourceUri) {
 				logger.debug("Removed resource handler: {}", resourceUri);
 			}
 			else {
-				logger.warn("Resource with URI '{}' not found", resourceUri);
+				logger.warn("Failed to remove a resource with URI '{}' (not found)", resourceUri);
 			}
 			return Mono.empty();
 		});
@@ -554,7 +554,7 @@ public Mono<Void> removeResourceTemplate(String uriTemplate) {
 				logger.debug("Removed resource template: {}", uriTemplate);
 			}
 			else {
-				logger.warn("Ignore as a Resource Template with URI '{}' not found", uriTemplate);
+				logger.warn("Failed to remove a resource template with URI '{}' (not found)", uriTemplate);
 			}
 			return Mono.empty();
 		});
@@ -677,7 +677,7 @@ public Mono<Void> removePrompt(String promptName) {
 				return Mono.empty();
 			}
 			else {
-				logger.warn("Ignore as a Prompt with name '{}' not found", promptName);
+				logger.warn("Failed to remove a prompt with name '{}' (not found)", promptName);
 			}
 
 			return Mono.empty();

mcp-core/src/main/java/io/modelcontextprotocol/server/transport/HttpServletStreamableServerTransportProvider.java

@@ -200,7 +200,7 @@ public Mono<Void> notifyClients(String method, Object params) {
 					session.sendNotification(method, params).block();
 				}
 				catch (Exception e) {
-					logger.error("Failed to send message to session {}: {}", session.getId(), e.getMessage());
+					logger.info("Failed to send message to session {}: {}", session.getId(), e.getMessage());
 				}
 			});
 		});
@@ -233,12 +233,11 @@ public Mono<Void> closeGracefully() {
 					session.closeGracefully().block();
 				}
 				catch (Exception e) {
-					logger.error("Failed to close session {}: {}", session.getId(), e.getMessage());
+					logger.warn("Failed to close session {}: {}", session.getId(), e.getMessage());
 				}
 			});
 
 			this.sessions.clear();
-			logger.debug("Graceful shutdown completed");
 		}).then().doOnSuccess(v -> {
 			sessions.clear();
 			logger.debug("Graceful shutdown completed");

mcp-core/src/main/java/io/modelcontextprotocol/spec/McpClientSession.java

@@ -124,7 +124,7 @@ public McpClientSession(Duration requestTimeout, McpClientTransport transport,
 
 	private void dismissPendingResponses() {
 		this.pendingResponses.forEach((id, sink) -> {
-			logger.warn("Abruptly terminating exchange for request {}", id);
+			logger.info("Abruptly terminating exchange for request {}", id);
 			sink.error(new RuntimeException("MCP session with server terminated"));
 		});
 		this.pendingResponses.clear();
@@ -257,7 +257,8 @@ public <T> Mono<T> sendRequest(String method, Object requestParams, TypeRef<T> t
 			});
 		})).timeout(this.requestTimeout).handle((jsonRpcResponse, deliveredResponseSink) -> {
 			if (jsonRpcResponse.error() != null) {
-				logger.error("Error handling request: {}", jsonRpcResponse.error());
+				logger.info("Server returned a JSON-RPC error when calling method {}: {}", method,
+						jsonRpcResponse.error());
 				deliveredResponseSink.error(new McpError(jsonRpcResponse.error()));
 			}
 			else {

mcp-core/src/main/java/io/modelcontextprotocol/spec/McpServerSession.java

@@ -256,8 +256,8 @@ else if (message instanceof McpSchema.JSONRPCNotification notification) {
 				// happening first
 				logger.debug("Received notification: {}", notification);
 				// TODO: in case of error, should the POST request be signalled?
-				return handleIncomingNotification(notification, transportContext)
-					.doOnError(error -> logger.error("Error handling notification: {}", error.getMessage()));
+				return handleIncomingNotification(notification, transportContext).doOnError(
+						error -> logger.warn("Error handling notification {}: {}", notification, error.getMessage()));
 			}
 			else {
 				logger.warn("Received unknown message type: {}", message);

mcp-json-jackson2/src/main/java/io/modelcontextprotocol/json/schema/jackson2/DefaultJsonSchemaValidator.java

@@ -84,11 +84,9 @@ public ValidationResponse validate(Map<String, Object> schema, Object structured
 
 		}
 		catch (JsonProcessingException e) {
-			logger.error("Failed to validate CallToolResult: Error parsing schema: {}", e);
 			return ValidationResponse.asInvalid("Error parsing tool JSON Schema: " + e.getMessage());
 		}
 		catch (Exception e) {
-			logger.error("Failed to validate CallToolResult: Unexpected error: {}", e);
 			return ValidationResponse.asInvalid("Unexpected validation error: " + e.getMessage());
 		}
 	}
@@ -113,7 +111,6 @@ public ValidationResponse validateSchema(Map<String, Object> schema) {
 			return ValidationResponse.asValid(null);
 		}
 		catch (Exception e) {
-			logger.error("Failed to validate schema definition: {}", e.getMessage());
 			return ValidationResponse.asInvalid("Failed to validate schema definition: " + e.getMessage());
 		}
 	}

mcp-json-jackson3/src/main/java/io/modelcontextprotocol/json/schema/jackson3/DefaultJsonSchemaValidator.java

@@ -83,11 +83,9 @@ public ValidationResponse validate(Map<String, Object> schema, Object structured
 
 		}
 		catch (JacksonException e) {
-			logger.error("Failed to validate CallToolResult: Error parsing schema: {}", e);
 			return ValidationResponse.asInvalid("Error parsing tool JSON Schema: " + e.getMessage());
 		}
 		catch (Exception e) {
-			logger.error("Failed to validate CallToolResult: Unexpected error: {}", e);
 			return ValidationResponse.asInvalid("Unexpected validation error: " + e.getMessage());
 		}
 	}
@@ -112,7 +110,6 @@ public ValidationResponse validateSchema(Map<String, Object> schema) {
 			return ValidationResponse.asValid(null);
 		}
 		catch (Exception e) {
-			logger.error("Failed to validate schema definition: {}", e.getMessage());
 			return ValidationResponse.asInvalid("Failed to validate schema definition: " + e.getMessage());
 		}
 	}

mcp-test/src/test/resources/logback-test.xml

@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE configuration>
+
+<configuration>
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
+        </encoder>
+    </appender>
+
+    <appender name="DOCKER" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level [DOCKER] %logger{36} - %msg%n</pattern>
+        </encoder>
+    </appender>
+
+    <!-- Testcontainers framework -->
+    <logger name="org.testcontainers" level="INFO" additivity="false">
+        <appender-ref ref="DOCKER"/>
+    </logger>
+
+    <!-- Docker Java client -->
+    <logger name="com.github.dockerjava" level="INFO" additivity="false">
+        <appender-ref ref="DOCKER"/>
+    </logger>
+
+    <!-- Container output (tc.<image-name> format used by Testcontainers) -->
+    <logger name="tc" level="INFO" additivity="false">
+        <appender-ref ref="DOCKER"/>
+    </logger>
+
+    <logger name="io.modelcontextprotocol" level="INFO"/>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT"/>
+    </root>
+</configuration>