fix: deduplicate getDefaultAPIBase and add empty apiBase validation

Export GetDefaultAPIBase from pkg/providers and reuse it in STT
resolution instead of the duplicated getDefaultSTTBase. Skip model
configs with unknown protocols that resolve to an empty API base.

Resolves Copilot review comments on PR #635.

cmd/picoclaw/cmd_gateway.go

@@ -241,14 +241,3 @@ func setupCronTool(
 
 	return cronService
 }
-
-func getDefaultSTTBase(protocol string) string {
-	switch protocol {
-	case "openai":
-		return "https://api.openai.com/v1"
-	case "groq":
-		return "https://api.groq.com/openai/v1"
-	default:
-		return ""
-	}
-}

cmd/picoclaw/stt_resolution.go

@@ -20,7 +20,10 @@ func resolveSTTTranscriber(cfg *config.Config) voice.Transcriber {
 				protocol, modelID := providers.ExtractProtocol(mc.Model)
 				apiBase := mc.APIBase
 				if apiBase == "" {
-					apiBase = getDefaultSTTBase(protocol)
+					apiBase = providers.GetDefaultAPIBase(protocol)
+				}
+				if apiBase == "" {
+					continue // unknown protocol, skip this entry
 				}
 				return voice.NewOpenAICompatTranscriber(mc.APIKey, apiBase, modelID)
 			}

cmd/picoclaw/stt_resolution_test.go

@@ -7,22 +7,28 @@ import (
 	"github.com/sipeed/picoclaw/pkg/voice"
 )
 
-func TestGetDefaultSTTBase(t *testing.T) {
+func TestResolveSTTTranscriber_UnknownProtocolSkipped(t *testing.T) {
-	tests := []struct {
+	// stt_model points to an entry with an unknown protocol and no api_base.
-		protocol string
+	// The unknown protocol resolves to an empty API base, so this entry must be
-		expected string
+	// skipped (continue) and the function should fall through to return nil.
-	}{
+	cfg := &config.Config{
-		{"openai", "https://api.openai.com/v1"},
+		Agents: config.AgentsConfig{
-		{"groq", "https://api.groq.com/openai/v1"},
+			Defaults: config.AgentDefaults{
-		{"unknown", ""},
+				STTModel: "whisper",
-		{"", ""},
+			},
+		},
+		ModelList: []config.ModelConfig{
+			{
+				ModelName: "whisper",
+				Model:     "unknownprotocol/whisper-1",
+				APIKey:    "sk-test",
+			},
+		},
 	}
-	for _, tt := range tests {
+
-		t.Run(tt.protocol, func(t *testing.T) {
+	tr := resolveSTTTranscriber(cfg)
-			if got := getDefaultSTTBase(tt.protocol); got != tt.expected {
+	if tr != nil {
-				t.Errorf("getDefaultSTTBase(%q) = %q, want %q", tt.protocol, got, tt.expected)
+		t.Error("expected nil - unknown protocol with no api_base should be skipped")
-			}
-		})
 	}
 }
 

pkg/providers/factory_provider.go

@@ -82,7 +82,7 @@ func CreateProviderFromConfig(cfg *config.ModelConfig) (LLMProvider, string, err
 		}
 		apiBase := cfg.APIBase
 		if apiBase == "" {
-			apiBase = getDefaultAPIBase(protocol)
+			apiBase = GetDefaultAPIBase(protocol)
 		}
 		return NewHTTPProviderWithMaxTokensField(cfg.APIKey, apiBase, cfg.Proxy, cfg.MaxTokensField), modelID, nil
 
@@ -95,7 +95,7 @@ func CreateProviderFromConfig(cfg *config.ModelConfig) (LLMProvider, string, err
 		}
 		apiBase := cfg.APIBase
 		if apiBase == "" {
-			apiBase = getDefaultAPIBase(protocol)
+			apiBase = GetDefaultAPIBase(protocol)
 		}
 		return NewHTTPProviderWithMaxTokensField(cfg.APIKey, apiBase, cfg.Proxy, cfg.MaxTokensField), modelID, nil
 
@@ -155,8 +155,9 @@ func CreateProviderFromConfig(cfg *config.ModelConfig) (LLMProvider, string, err
 	}
 }
 
-// getDefaultAPIBase returns the default API base URL for a given protocol.
+// GetDefaultAPIBase returns the default API base URL for a given protocol.
-func getDefaultAPIBase(protocol string) string {
+// Returns an empty string if the protocol is unknown.
+func GetDefaultAPIBase(protocol string) string {
 	switch protocol {
 	case "openai":
 		return "https://api.openai.com/v1"