feat: support MCP tool calls

Author: Pasichniuk

src/main/java/com/epam/aidial/deployment/manager/service/McpService.java

@@ -10,7 +10,9 @@
 import io.modelcontextprotocol.spec.McpSchema;
 import lombok.RequiredArgsConstructor;
 import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.lang3.exception.ExceptionUtils;
 import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
 
 import java.util.function.BiFunction;
 
@@ -48,6 +50,21 @@ private <T> T get(String deploymentId, String nextCursor, BiFunction<McpSyncClie
         }
     }
 
+    @Transactional(readOnly = true)
+    public McpSchema.CallToolResult callTool(String deploymentId, McpSchema.CallToolRequest callToolRequest) {
+        var deployment = getDeployment(deploymentId);
+        var endpointPath = mcpEndpointPathResolver.resolveEndpointPath(deployment);
+
+        try (var mcpClient = mcpClientFactory.create(deployment.getUrl(), endpointPath, deployment.getTransport())) {
+            mcpClient.initialize();
+            return mcpClient.callTool(callToolRequest);
+        } catch (Exception e) {
+            String reason = ExceptionUtils.getRootCause(e).getMessage();
+            throw new McpClientException(("Failed to call a tool via MCP server. Deployment id: %s. Transport: '%s'. Path: '%s'. Reason: %s")
+                    .formatted(deploymentId, deployment.getTransport(), deployment.getMcpEndpointPath(), reason), e);
+        }
+    }
+
     private McpDeployment getDeployment(String deploymentId) {
         var deployment = deploymentService.getDeployment(deploymentId)
                 .orElseThrow(() -> new EntityNotFoundException("Deployment not found by id: %s"

src/main/java/com/epam/aidial/deployment/manager/web/controller/McpController.java

@@ -3,9 +3,12 @@
 import com.epam.aidial.deployment.manager.service.McpService;
 import io.modelcontextprotocol.spec.McpSchema;
 import lombok.RequiredArgsConstructor;
+import org.springframework.http.MediaType;
 import org.springframework.util.MimeTypeUtils;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.bind.annotation.RestController;
@@ -24,6 +27,12 @@ public McpSchema.ListToolsResult getTools(@PathVariable String deploymentId,
         return mcpService.getTools(deploymentId, nextCursor);
     }
 
+    @PostMapping(path = "/{deploymentId}/call-tool", produces = MediaType.APPLICATION_JSON_VALUE)
+    public McpSchema.CallToolResult callTool(@PathVariable String deploymentId,
+                                             @RequestBody McpSchema.CallToolRequest callToolRequest) {
+        return mcpService.callTool(deploymentId, callToolRequest);
+    }
+
     @GetMapping(path = "/{deploymentId}/resources",
             produces = MimeTypeUtils.APPLICATION_JSON_VALUE)
     public McpSchema.ListResourcesResult getResources(@PathVariable String deploymentId,

src/test/java/com/epam/aidial/deployment/manager/service/McpServiceTest.java

@@ -205,6 +205,29 @@ void testGetTools_withNullCursor() {
         verify(mcpSyncClient).listTools(null);
     }
 
+    @Test
+    void testCallTool() {
+        // Given
+        var deployment = createDeployment();
+        String endpointPath = "/sseCustom";
+        deployment.setMcpEndpointPath(endpointPath);
+        deployment.setTransport(McpTransport.SSE);
+
+        when(deploymentService.getDeployment(DEPLOYMENT_ID)).thenReturn(Optional.of(deployment));
+        when(mcpClientFactory.create(DEPLOYMENT_URL, endpointPath, McpTransport.SSE)).thenReturn(mcpSyncClient);
+
+        var callToolRequest = Mockito.mock(McpSchema.CallToolRequest.class);
+        var expectedCallToolResult = Mockito.mock(McpSchema.CallToolResult.class);
+        when(mcpSyncClient.callTool(callToolRequest)).thenReturn(expectedCallToolResult);
+
+        // When
+        var result = mcpService.callTool(DEPLOYMENT_ID, callToolRequest);
+
+        // Then
+        assertThat(result).isEqualTo(expectedCallToolResult);
+        verify(mcpSyncClient).callTool(callToolRequest);
+    }
+
     private McpDeployment createDeployment() {
         var deployment = new McpDeployment();
         deployment.setId(DEPLOYMENT_ID);

src/test/java/com/epam/aidial/deployment/manager/web/controller/none/McpControllerTest.java

@@ -4,12 +4,15 @@
 import com.epam.aidial.deployment.manager.service.McpService;
 import com.epam.aidial.deployment.manager.utils.ResourceUtils;
 import com.epam.aidial.deployment.manager.web.controller.McpController;
+import com.fasterxml.jackson.core.type.TypeReference;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import io.modelcontextprotocol.spec.McpSchema;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
 import org.springframework.context.annotation.Import;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.MediaType;
 import org.springframework.test.context.bean.override.mockito.MockitoBean;
 import org.springframework.test.json.JsonCompareMode;
 
@@ -18,6 +21,7 @@
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
 import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
 
@@ -27,6 +31,9 @@
 })
 class McpControllerTest extends AbstractControllerNoneSecureTest {
 
+    private static final String CALL_TOOL_REQUEST_DTO_JSON_PATH = "/mcp/call_tool_request_dto.json";
+    private static final String CALL_TOOL_RESULT_DTO_JSON_PATH = "/mcp/call_tool_result_dto.json";
+
     private static final String DEPLOYMENT_ID = String.valueOf(UUID.randomUUID());
     private static final String NEXT_CURSOR = "some-cursor";
 
@@ -136,4 +143,23 @@ void testGetPromptsWithCursor() throws Exception {
 
         verify(mcpService).getPrompts(DEPLOYMENT_ID, NEXT_CURSOR);
     }
+
+    @Test
+    void testCallTool() throws Exception {
+        var callToolRequestDtoJson = ResourceUtils.readResource(CALL_TOOL_REQUEST_DTO_JSON_PATH);
+        var callToolRequestDto = objectMapper.readValue(callToolRequestDtoJson, new TypeReference<McpSchema.CallToolRequest>() {
+        });
+
+        var callToolResultDtoJson = ResourceUtils.readResource(CALL_TOOL_RESULT_DTO_JSON_PATH);
+        var callToolResultDto = objectMapper.readValue(callToolResultDtoJson, new TypeReference<McpSchema.CallToolResult>() {
+        });
+
+        when(mcpService.callTool(DEPLOYMENT_ID, callToolRequestDto)).thenReturn(callToolResultDto);
+
+        mockMvc.perform(post("/api/v1/deployments/mcp/{deploymentId}/call-tool", DEPLOYMENT_ID)
+                    .header(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_JSON_VALUE)
+                    .content(callToolRequestDtoJson))
+                .andExpect(status().isOk())
+                .andExpect(content().json(callToolResultDtoJson, JsonCompareMode.LENIENT));
+    }
 }

src/test/resources/mcp/call_tool_request_dto.json

@@ -0,0 +1,7 @@
+{
+  "name": "get_simple_price",
+  "arguments": {
+    "vs_currencies": "usd",
+    "ids": "bitcoin"
+  }
+}

src/test/resources/mcp/call_tool_result_dto.json

@@ -0,0 +1,8 @@
+{
+  "content": [
+    {
+      "type": "text",
+      "text": "{\n  \"bitcoin\": {\n    \"usd\": 93575\n  }\n}"
+    }
+  ]
+}