Align tool-call parsing across Go/JS and pass quality gates

internal/adapter/gemini/convert_messages.go

@@ -1,11 +1,20 @@
 package gemini
 
-import "strings"
+import (
+	"fmt"
+	"strings"
+)
 
 const maxGeminiRawPromptChars = 1024
 
 func geminiMessagesFromRequest(req map[string]any) []any {
 	out := make([]any, 0, 8)
+	toolCallCounter := 0
+	nextToolCallID := func() string {
+		toolCallCounter++
+		return fmt.Sprintf("call_gemini_%d", toolCallCounter)
+	}
+	lastToolCallIDByName := map[string]string{}
 	if sys := normalizeGeminiSystemInstruction(req["systemInstruction"]); strings.TrimSpace(sys) != "" {
 		out = append(out, map[string]any{
 			"role":    "system",
@@ -61,8 +70,11 @@ func geminiMessagesFromRequest(req map[string]any) []any {
 				if name := strings.TrimSpace(asString(fnCall["name"])); name != "" {
 					callID := strings.TrimSpace(asString(fnCall["id"]))
 					if callID == "" {
-						callID = "call_gemini"
+						if callID = strings.TrimSpace(asString(fnCall["call_id"])); callID == "" {
+							callID = nextToolCallID()
+						}
 					}
+					lastToolCallIDByName[strings.ToLower(name)] = callID
 					out = append(out, map[string]any{
 						"role": "assistant",
 						"tool_calls": []any{
@@ -91,7 +103,10 @@ func geminiMessagesFromRequest(req map[string]any) []any {
 					callID = strings.TrimSpace(asString(fnResp["tool_call_id"]))
 				}
 				if callID == "" {
-					callID = "call_gemini"
+					callID = strings.TrimSpace(lastToolCallIDByName[strings.ToLower(name)])
+				}
+				if callID == "" {
+					callID = nextToolCallID()
 				}
 				content := fnResp["response"]
 				if content == nil {

internal/adapter/gemini/convert_messages_test.go

@@ -82,3 +82,48 @@ func TestGeminiMessagesFromRequestPreservesUnknownPartAsRawJSONText(t *testing.T
 		t.Fatalf("expected raw base64 payload not to be embedded, got %q", content)
 	}
 }
+
+func TestGeminiMessagesFromRequestBackfillsFunctionResponseCallIDByName(t *testing.T) {
+	req := map[string]any{
+		"contents": []any{
+			map[string]any{
+				"role": "model",
+				"parts": []any{
+					map[string]any{
+						"functionCall": map[string]any{
+							"name": "search_web",
+							"args": map[string]any{"query": "docs"},
+						},
+					},
+				},
+			},
+			map[string]any{
+				"role": "user",
+				"parts": []any{
+					map[string]any{
+						"functionResponse": map[string]any{
+							"name":     "search_web",
+							"response": map[string]any{"ok": true},
+						},
+					},
+				},
+			},
+		},
+	}
+
+	got := geminiMessagesFromRequest(req)
+	if len(got) != 2 {
+		t.Fatalf("expected two normalized messages, got %#v", got)
+	}
+	assistant, _ := got[0].(map[string]any)
+	tc, _ := assistant["tool_calls"].([]any)
+	call, _ := tc[0].(map[string]any)
+	callID, _ := call["id"].(string)
+	if !strings.HasPrefix(callID, "call_gemini_") {
+		t.Fatalf("expected generated call id prefix, got %#v", call)
+	}
+	toolMsg, _ := got[1].(map[string]any)
+	if toolMsg["tool_call_id"] != callID {
+		t.Fatalf("expected tool response to inherit generated call id, tool=%#v call=%#v", toolMsg, call)
+	}
+}