Improve logging in server and some updates for demo

examples/calendar/src/main/java/io/helidon/extensions/mcp/examples/calendar/ListCalendarEventTool.java

@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2025 Oracle and/or its affiliates.
+ *
+ * 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
+ *
+ *     http://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.
+ */
+
+package io.helidon.extensions.mcp.examples.calendar;
+
+import java.util.List;
+import java.util.function.Function;
+
+import io.helidon.extensions.mcp.server.McpParameters;
+import io.helidon.extensions.mcp.server.McpRequest;
+import io.helidon.extensions.mcp.server.McpTool;
+import io.helidon.extensions.mcp.server.McpToolContent;
+import io.helidon.extensions.mcp.server.McpToolContents;
+
+/**
+ * MCP tool to list calendar events. Available as an alternative to using
+ * resources.
+ */
+final class ListCalendarEventTool implements McpTool {
+    private static final String SCHEMA = """
+            {
+                "type": "object",
+                "description": "List calendar events",
+                "properties": {
+                    "date": {
+                        "description": "Event date in the following format YYYY-MM-DD",
+                        "type": "string"
+                    }
+                }
+            }
+            """;
+
+    private final Calendar calendar;
+
+    ListCalendarEventTool(Calendar calendar) {
+        this.calendar = calendar;
+    }
+
+    @Override
+    public String name() {
+        return "list-calendar-event";
+    }
+
+    @Override
+    public String description() {
+        return "List calendar events.";
+    }
+
+    @Override
+    public String schema() {
+        return SCHEMA;
+    }
+
+    @Override
+    public Function<McpRequest, List<McpToolContent>> tool() {
+        return this::listCalendarEvents;
+    }
+
+    private List<McpToolContent> listCalendarEvents(McpRequest request) {
+        McpParameters mcpParameters = request.parameters();
+
+        String date = mcpParameters.get("date")
+                .asString()
+                .orElse(null);
+
+        String entries = calendar.readContentMatchesLine(line -> date == null || line.contains(date));
+        return List.of(McpToolContents.textContent(entries));
+    }
+}

examples/calendar/src/main/java/io/helidon/extensions/mcp/examples/calendar/Main.java

@@ -52,6 +52,7 @@ static void setUpRoute(HttpRouting.Builder builder) {
                 McpServerConfig.builder()
                         .config(config.get("mcp.server"))
                         .addTool(new AddCalendarEventTool(calendar))
+                        .addTool(new ListCalendarEventTool(calendar))
                         .addResource(new CalendarEventResource(calendar))
                         .addPrompt(new CreateCalendarEventPrompt())
                         .addCompletion(new CreateCalendarEventPromptCompletion())

examples/calendar/src/test/java/io/helidon/extensions/mcp/examples/calendar/BaseTest.java

@@ -36,7 +36,6 @@
 import static org.hamcrest.Matchers.hasItems;
 import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
-import static org.hamcrest.Matchers.nullValue;
 import static org.hamcrest.Matchers.startsWith;
 
 @TestMethodOrder(OrderAnnotation.class)
@@ -54,21 +53,31 @@ static void routing(HttpRouting.Builder builder) {
     void testToolList() {
         McpSchema.ListToolsResult listTool = client().listTools();
         List<McpSchema.Tool> tools = listTool.tools();
-        assertThat(tools.size(), is(1));
+        assertThat(tools.size(), is(2));
 
-        McpSchema.Tool tool = tools.getFirst();
-        assertThat(tool.name(), is("add-calendar-event"));
-        assertThat(tool.description(), is("Adds a new event to the calendar."));
+        McpSchema.Tool tool1 = tools.getFirst();
+        assertThat(tool1.name(), is("add-calendar-event"));
+        assertThat(tool1.description(), is("Adds a new event to the calendar."));
 
-        McpSchema.JsonSchema schema = tool.inputSchema();
-        assertThat(schema.type(), is("object"));
-        assertThat(schema.properties().keySet(), hasItems("name", "date", "attendees"));
+        McpSchema.JsonSchema schema1 = tool1.inputSchema();
+        assertThat(schema1.type(), is("object"));
+        assertThat(schema1.properties().keySet(), hasItems("name", "date", "attendees"));
+
+        McpSchema.Tool tool2 = tools.getLast();
+        assertThat(tool2.name(), is("list-calendar-event"));
+        assertThat(tool2.description(), is("List calendar events."));
+
+        McpSchema.JsonSchema schema2 = tool2.inputSchema();
+        assertThat(schema2.type(), is("object"));
+        assertThat(schema2.properties().keySet(), hasItems("date"));
     }
 
     @Test
     @Order(2)
-    void testToolCall() {
-        Map<String, Object> arguments = Map.of("name", "Frank-birthday", "date", "2021-04-20", "attendees", List.of("Frank"));
+    void testAddToolCall() {
+        Map<String, Object> arguments = Map.of("name", "Frank-birthday",
+                                               "date", "2021-04-20",
+                                               "attendees", List.of("Frank"));
         McpSchema.CallToolRequest request = new McpSchema.CallToolRequest("add-calendar-event", arguments);
         McpSchema.CallToolResult result = client().callTool(request);
         assertThat(result.isError(), is(false));
@@ -86,6 +95,25 @@ void testToolCall() {
 
     @Test
     @Order(3)
+    void testListToolCall() {
+        Map<String, Object> arguments = Map.of("date", "2021-04-20");
+        McpSchema.CallToolRequest request = new McpSchema.CallToolRequest("list-calendar-event", arguments);
+        McpSchema.CallToolResult result = client().callTool(request);
+        assertThat(result.isError(), is(false));
+
+        List<McpSchema.Content> contents = result.content();
+        assertThat(contents.size(), is(1));
+
+        McpSchema.Content content = contents.getFirst();
+        assertThat(content.type(), is("text"));
+        assertThat(content, instanceOf(McpSchema.TextContent.class));
+
+        McpSchema.TextContent textContent = (McpSchema.TextContent) content;
+        assertThat(textContent.text(), containsString("Frank-birthday"));
+    }
+
+    @Test
+    @Order(4)
     void testPromptList() {
         McpSchema.ListPromptsResult listPrompt = client().listPrompts();
         List<McpSchema.Prompt> prompts = listPrompt.prompts();
@@ -116,7 +144,7 @@ void testPromptList() {
     }
 
     @Test
-    @Order(4)
+    @Order(5)
     void testPromptCall() {
         Map<String, Object> arguments = Map.of("name", "Frank-birthday", "date", "2021-04-20", "attendees", "Frank");
         McpSchema.GetPromptRequest request = new McpSchema.GetPromptRequest("create-event", arguments);
@@ -138,7 +166,7 @@ void testPromptCall() {
     }
 
     @Test
-    @Order(5)
+    @Order(6)
     void testResourceList() {
         McpSchema.ListResourcesResult result = client().listResources();
         List<McpSchema.Resource> resources = result.resources();
@@ -152,7 +180,7 @@ void testResourceList() {
     }
 
     @Test
-    @Order(6)
+    @Order(7)
     void testResourceCall() {
         String uri = client().listResources().resources().getFirst().uri();
         McpSchema.ReadResourceRequest request = new McpSchema.ReadResourceRequest(uri);
@@ -171,7 +199,7 @@ void testResourceCall() {
     }
 
     @Test
-    @Order(7)
+    @Order(8)
     void testResourceTemplateList() {
         McpSchema.ListResourceTemplatesResult result = client().listResourceTemplates();
         List<McpSchema.ResourceTemplate> templates = result.resourceTemplates();
@@ -185,7 +213,7 @@ void testResourceTemplateList() {
     }
 
     @Test
-    @Order(8)
+    @Order(9)
     void testResourceTemplateCall() {
         McpSchema.ReadResourceRequest request = new McpSchema.ReadResourceRequest("file://events/Frank-birthday");
         McpSchema.ReadResourceResult result = client().readResource(request);
@@ -202,7 +230,7 @@ void testResourceTemplateCall() {
     }
 
     @Test
-    @Order(9)
+    @Order(10)
     void testCalendarEventPromptCompletion() {
         McpSchema.CompleteRequest request1 = new McpSchema.CompleteRequest(
                 new McpSchema.PromptReference("create-event"),
@@ -231,7 +259,7 @@ void testCalendarEventPromptCompletion() {
     }
 
     @Test
-    @Order(10)
+    @Order(11)
     void testCalendarEventResourceCompletion() {
         McpSchema.CompleteRequest request = new McpSchema.CompleteRequest(
                 new McpSchema.ResourceReference(URI_TEMPLATE),

examples/weather-application/mcp-server-declarative/src/main/resources/logging.properties

@@ -0,0 +1,22 @@
+#
+# Copyright (c) 2025 Oracle and/or its affiliates.
+#
+# 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
+#
+#     http://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.
+#
+handlers=io.helidon.logging.jul.HelidonConsoleHandler
+
+# HelidonConsoleHandler uses a SimpleFormatter subclass that replaces "!thread!" with the current thread
+java.util.logging.SimpleFormatter.format=%1$tY.%1$tm.%1$td %1$tH:%1$tM:%1$tS %4$s %3$s !thread!: %5$s%6$s%n
+
+.level=INFO
+io.helidon.extensions.mcp.server.McpServerFeature.level=FINEST

server/src/main/java/io/helidon/extensions/mcp/server/McpJsonRpc.java

@@ -16,7 +16,9 @@
 
 package io.helidon.extensions.mcp.server;
 
+import java.io.ByteArrayOutputStream;
 import java.io.StringReader;
+import java.nio.charset.StandardCharsets;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
@@ -28,11 +30,17 @@
 import jakarta.json.JsonObject;
 import jakarta.json.JsonObjectBuilder;
 import jakarta.json.JsonReaderFactory;
+import jakarta.json.JsonStructure;
 import jakarta.json.JsonValue;
+import jakarta.json.JsonWriter;
+import jakarta.json.JsonWriterFactory;
+import jakarta.json.stream.JsonGenerator;
 
 final class McpJsonRpc {
     static final JsonBuilderFactory JSON_BUILDER_FACTORY = Json.createBuilderFactory(Map.of());
     static final JsonReaderFactory JSON_READER_FACTORY = Json.createReaderFactory(Map.of());
+    static final JsonWriterFactory JSON_PP_WRITER_FACTORY = Json.createWriterFactory(
+            Map.of(JsonGenerator.PRETTY_PRINTING, true));
 
     private static final Map<String, JsonObject> CACHE = new ConcurrentHashMap<>();
     private static final JsonObject EMPTY_OBJECT_SCHEMA = JSON_BUILDER_FACTORY.createObjectBuilder()
@@ -481,4 +489,12 @@ static JsonObject toJson(McpCompletionContent content) {
     static JsonObject disconnectSession() {
         return JSON_BUILDER_FACTORY.createObjectBuilder().add("disconnect", true).build();
     }
+
+    static String prettyPrint(JsonStructure json) {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        try (JsonWriter writer = JSON_PP_WRITER_FACTORY.createWriter(baos)) {
+            writer.write(json);
+        }
+        return baos.toString(StandardCharsets.UTF_8);
+    }
 }