diff --git a/mcp-core/src/main/java/io/modelcontextprotocol/client/McpAsyncClient.java b/mcp-core/src/main/java/io/modelcontextprotocol/client/McpAsyncClient.java index 53a05aec3..2d1f4b43c 100644 --- a/mcp-core/src/main/java/io/modelcontextprotocol/client/McpAsyncClient.java +++ b/mcp-core/src/main/java/io/modelcontextprotocol/client/McpAsyncClient.java @@ -402,6 +402,7 @@ public Mono closeGracefully() { // -------------------------- // Initialization // -------------------------- + /** * The initialization phase should be the first interaction between client and server. * The client will ensure it happens in case it has not been explicitly called and in @@ -448,6 +449,7 @@ public Mono ping() { // -------------------------- // Roots // -------------------------- + /** * Adds a new root to the client's root list. * @param root The root to add. @@ -625,13 +627,13 @@ private McpSchema.CallToolResult validateToolResult(String toolName, McpSchema.C * @return A Mono that emits the list of all tools result */ public Mono listTools() { - return this.listTools(McpSchema.FIRST_PAGE) - .expand(result -> (result.nextCursor() != null) ? this.listTools(result.nextCursor()) : Mono.empty()) - .reduce(new McpSchema.ListToolsResult(new ArrayList<>(), null), (allToolsResult, result) -> { - allToolsResult.tools().addAll(result.tools()); - return allToolsResult; - }) - .map(result -> new McpSchema.ListToolsResult(Collections.unmodifiableList(result.tools()), null)); + return this.listTools(McpSchema.FIRST_PAGE).expand(result -> { + String next = result.nextCursor(); + return (next != null && !next.isEmpty()) ? this.listTools(next) : Mono.empty(); + }).reduce(new McpSchema.ListToolsResult(new ArrayList<>(), null), (allToolsResult, result) -> { + allToolsResult.tools().addAll(result.tools()); + return allToolsResult; + }).map(result -> new McpSchema.ListToolsResult(Collections.unmodifiableList(result.tools()), null)); } /** diff --git a/mcp-core/src/test/java/io/modelcontextprotocol/client/McpAsyncClientTests.java b/mcp-core/src/test/java/io/modelcontextprotocol/client/McpAsyncClientTests.java index 970d8f257..48bf1da5b 100644 --- a/mcp-core/src/test/java/io/modelcontextprotocol/client/McpAsyncClientTests.java +++ b/mcp-core/src/test/java/io/modelcontextprotocol/client/McpAsyncClientTests.java @@ -4,24 +4,22 @@ package io.modelcontextprotocol.client; +import java.util.List; +import java.util.Map; +import java.util.Objects; +import java.util.Set; +import java.util.concurrent.atomic.AtomicReference; +import java.util.function.Function; +import java.util.stream.Collectors; + import io.modelcontextprotocol.json.TypeRef; import io.modelcontextprotocol.spec.McpClientTransport; import io.modelcontextprotocol.spec.McpSchema; import io.modelcontextprotocol.spec.ProtocolVersions; - import org.junit.jupiter.api.Test; - -import com.fasterxml.jackson.core.JsonProcessingException; - import reactor.core.publisher.Mono; import reactor.test.StepVerifier; -import java.util.List; -import java.util.Map; -import java.util.Objects; -import java.util.concurrent.atomic.AtomicReference; -import java.util.function.Function; - import static io.modelcontextprotocol.util.McpJsonMapperUtils.JSON_MAPPER; import static org.assertj.core.api.Assertions.assertThat; import static org.assertj.core.api.Assertions.assertThatCode; @@ -40,8 +38,7 @@ class McpAsyncClientTests { private static final String CONTEXT_KEY = "context.key"; - private McpClientTransport createMockTransportForToolValidation(boolean hasOutputSchema, boolean invalidOutput) - throws JsonProcessingException { + private McpClientTransport createMockTransportForToolValidation(boolean hasOutputSchema, boolean invalidOutput) { // Create tool with or without output schema Map inputSchemaMap = Map.of("type", "object", "properties", @@ -182,7 +179,7 @@ public java.lang.reflect.Type getType() { } @Test - void testCallToolWithOutputSchemaValidationSuccess() throws JsonProcessingException { + void testCallToolWithOutputSchemaValidationSuccess() { McpClientTransport transport = createMockTransportForToolValidation(true, false); McpAsyncClient client = McpClient.async(transport).enableCallToolSchemaCaching(true).build(); @@ -204,7 +201,7 @@ void testCallToolWithOutputSchemaValidationSuccess() throws JsonProcessingExcept } @Test - void testCallToolWithNoOutputSchemaSuccess() throws JsonProcessingException { + void testCallToolWithNoOutputSchemaSuccess() { McpClientTransport transport = createMockTransportForToolValidation(false, false); McpAsyncClient client = McpClient.async(transport).enableCallToolSchemaCaching(true).build(); @@ -226,7 +223,7 @@ void testCallToolWithNoOutputSchemaSuccess() throws JsonProcessingException { } @Test - void testCallToolWithOutputSchemaValidationFailure() throws JsonProcessingException { + void testCallToolWithOutputSchemaValidationFailure() { McpClientTransport transport = createMockTransportForToolValidation(true, true); McpAsyncClient client = McpClient.async(transport).enableCallToolSchemaCaching(true).build(); @@ -241,4 +238,73 @@ void testCallToolWithOutputSchemaValidationFailure() throws JsonProcessingExcept StepVerifier.create(client.closeGracefully()).verifyComplete(); } + @Test + void testListToolsWithEmptyCursor() { + McpSchema.Tool addTool = McpSchema.Tool.builder().name("add").description("calculate add").build(); + McpSchema.Tool subtractTool = McpSchema.Tool.builder() + .name("subtract") + .description("calculate subtract") + .build(); + McpSchema.ListToolsResult mockToolsResult = new McpSchema.ListToolsResult(List.of(addTool, subtractTool), ""); + + McpClientTransport transport = new McpClientTransport() { + Function, Mono> handler; + + @Override + public Mono connect( + Function, Mono> handler) { + return Mono.deferContextual(ctx -> { + this.handler = handler; + return Mono.empty(); + }); + } + + @Override + public Mono closeGracefully() { + return Mono.empty(); + } + + @Override + public Mono sendMessage(McpSchema.JSONRPCMessage message) { + if (!(message instanceof McpSchema.JSONRPCRequest request)) { + return Mono.empty(); + } + + McpSchema.JSONRPCResponse response; + if (McpSchema.METHOD_INITIALIZE.equals(request.method())) { + response = new McpSchema.JSONRPCResponse(McpSchema.JSONRPC_VERSION, request.id(), MOCK_INIT_RESULT, + null); + } + else if (McpSchema.METHOD_TOOLS_LIST.equals(request.method())) { + response = new McpSchema.JSONRPCResponse(McpSchema.JSONRPC_VERSION, request.id(), mockToolsResult, + null); + } + else { + return Mono.empty(); + } + + return handler.apply(Mono.just(response)).then(); + } + + @Override + public T unmarshalFrom(Object data, TypeRef typeRef) { + return JSON_MAPPER.convertValue(data, new TypeRef<>() { + @Override + public java.lang.reflect.Type getType() { + return typeRef.getType(); + } + }); + } + }; + + McpAsyncClient client = McpClient.async(transport).enableCallToolSchemaCaching(true).build(); + + Mono mono = client.listTools(); + McpSchema.ListToolsResult toolsResult = mono.block(); + assertThat(toolsResult).isNotNull(); + + Set names = toolsResult.tools().stream().map(McpSchema.Tool::name).collect(Collectors.toSet()); + assertThat(names).containsExactlyInAnyOrder("subtract", "add"); + } + }