review feedback: auto discover mcp tools

Signed-off-by: Huamin Chen <[email protected]>

Author: rootfs

config/config-mcp-classifier-example.yaml

@@ -30,7 +30,11 @@ classifier:
     transport_type: "http"           # HTTP transport
     url: "http://localhost:8090/mcp" # MCP server endpoint
 
-    tool_name: "classify_text"       # MCP tool name to call
+    # tool_name: Optional - auto-discovers classification tool if not specified
+    # Will search for tools like: classify_text, classify, categorize, etc.
+    # Uncomment to explicitly specify:
+    # tool_name: "classify_text"
+    
     threshold: 0.6                   # Confidence threshold
     timeout_seconds: 30              # Request timeout
 

examples/mcp-classifier-server/README.md

@@ -52,14 +52,21 @@ classifier:
     enabled: true
     transport_type: "http"
     url: "http://localhost:8090/mcp"
-    tool_name: "classify_text"
+    # tool_name: optional - auto-discovers classification tool if not specified
     threshold: 0.6
     timeout_seconds: 30
 
 categories: []  # Loaded dynamically from MCP
 default_model: openai/gpt-oss-20b
 ```
 
+**Tool Auto-Discovery:**
+The router automatically discovers classification tools from the MCP server by:
+1. Listing available tools on connection
+2. Looking for common names: `classify_text`, `classify`, `categorize`, `categorize_text`
+3. Pattern matching for tools containing "classif" in name/description
+4. Optionally specify `tool_name` to use a specific tool
+
 ## How It Works
 
 **Intelligent Routing Rules:**

src/semantic-router/pkg/config/config.go

@@ -35,7 +35,7 @@ type RouterConfig struct {
 			Args           []string          `yaml:"args,omitempty"`
 			Env            map[string]string `yaml:"env,omitempty"`
 			URL            string            `yaml:"url,omitempty"`
-			ToolName       string            `yaml:"tool_name"`
+			ToolName       string            `yaml:"tool_name,omitempty"` // Optional: will auto-discover if not specified
 			Threshold      float32           `yaml:"threshold"`
 			TimeoutSeconds int               `yaml:"timeout_seconds,omitempty"`
 		} `yaml:"mcp_category_model,omitempty"`

src/semantic-router/pkg/utils/classification/mcp_classifier.go

@@ -62,13 +62,9 @@ func (m *MCPCategoryClassifier) Init(cfg *config.RouterConfig) error {
 	if !cfg.Classifier.MCPCategoryModel.Enabled {
 		return fmt.Errorf("MCP category classifier is not enabled")
 	}
-	if cfg.Classifier.MCPCategoryModel.ToolName == "" {
-		return fmt.Errorf("MCP tool name is not specified")
-	}
 
-	// Store config and tool name
+	// Store config
 	m.config = cfg
-	m.toolName = cfg.Classifier.MCPCategoryModel.ToolName
 
 	// Create MCP client configuration
 	mcpConfig := mcpclient.ClientConfig{
@@ -99,10 +95,69 @@ func (m *MCPCategoryClassifier) Init(cfg *config.RouterConfig) error {
 	}
 
 	m.client = client
+
+	// Discover classification tool
+	if err := m.discoverClassificationTool(); err != nil {
+		client.Close()
+		return fmt.Errorf("failed to discover classification tool: %w", err)
+	}
+
 	observability.Infof("Successfully initialized MCP category classifier with tool '%s'", m.toolName)
 	return nil
 }
 
+// discoverClassificationTool finds the appropriate classification tool from available MCP tools
+func (m *MCPCategoryClassifier) discoverClassificationTool() error {
+	// If tool name is explicitly specified, use it
+	if m.config.Classifier.MCPCategoryModel.ToolName != "" {
+		m.toolName = m.config.Classifier.MCPCategoryModel.ToolName
+		observability.Infof("Using explicitly configured tool: %s", m.toolName)
+		return nil
+	}
+
+	// Otherwise, auto-discover by listing available tools
+	tools := m.client.GetTools()
+	if len(tools) == 0 {
+		return fmt.Errorf("no tools available from MCP server")
+	}
+
+	// Look for classification-related tools by common names
+	classificationToolNames := []string{
+		"classify_text",
+		"classify",
+		"categorize",
+		"categorize_text",
+	}
+
+	for _, toolName := range classificationToolNames {
+		for _, tool := range tools {
+			if tool.Name == toolName {
+				m.toolName = tool.Name
+				observability.Infof("Auto-discovered classification tool: %s - %s", m.toolName, tool.Description)
+				return nil
+			}
+		}
+	}
+
+	// If no common name found, look for tools that mention "classif" in name or description
+	for _, tool := range tools {
+		lowerName := strings.ToLower(tool.Name)
+		lowerDesc := strings.ToLower(tool.Description)
+		if strings.Contains(lowerName, "classif") || strings.Contains(lowerDesc, "classif") {
+			m.toolName = tool.Name
+			observability.Infof("Auto-discovered classification tool by pattern match: %s - %s", m.toolName, tool.Description)
+			return nil
+		}
+	}
+
+	// Log available tools for debugging
+	var toolNames []string
+	for _, tool := range tools {
+		toolNames = append(toolNames, tool.Name)
+	}
+	return fmt.Errorf("no classification tool found among available tools: %v", toolNames)
+}
+
 // Close closes the MCP client connection
 func (m *MCPCategoryClassifier) Close() error {
 	if m.client != nil {