Merge pull request #1131 from sowar1987/fix/gemini-malformed-function-call

Fix Gemini tool calling for Antigravity (malformed_function_call)

internal/cache/signature_cache_test.go

@@ -5,6 +5,8 @@ import (
 	"time"
 )
 
+const testModelName = "claude-sonnet-4-5"
+
 func TestCacheSignature_BasicStorageAndRetrieval(t *testing.T) {
 	ClearSignatureCache("")
 
@@ -12,10 +14,10 @@ func TestCacheSignature_BasicStorageAndRetrieval(t *testing.T) {
 	signature := "abc123validSignature1234567890123456789012345678901234567890"
 
 	// Store signature
-	CacheSignature("test-model", text, signature)
+	CacheSignature(testModelName, text, signature)
 
 	// Retrieve signature
-	retrieved := GetCachedSignature("test-model", text)
+	retrieved := GetCachedSignature(testModelName, text)
 	if retrieved != signature {
 		t.Errorf("Expected signature '%s', got '%s'", signature, retrieved)
 	}
@@ -28,28 +30,29 @@ func TestCacheSignature_DifferentModelGroups(t *testing.T) {
 	sig1 := "signature1_1234567890123456789012345678901234567890123456"
 	sig2 := "signature2_1234567890123456789012345678901234567890123456"
 
-	CacheSignature("claude-sonnet-4-5-thinking", text, sig1)
-	CacheSignature("gpt-4o", text, sig2)
+	geminiModel := "gemini-3-pro-preview"
+	CacheSignature(testModelName, text, sig1)
+	CacheSignature(geminiModel, text, sig2)
 
-	if GetCachedSignature("claude-sonnet-4-5-thinking", text) != sig1 {
+	if GetCachedSignature(testModelName, text) != sig1 {
 		t.Error("Claude signature mismatch")
 	}
-	if GetCachedSignature("gpt-4o", text) != sig2 {
-		t.Error("GPT signature mismatch")
+	if GetCachedSignature(geminiModel, text) != sig2 {
+		t.Error("Gemini signature mismatch")
 	}
 }
 
 func TestCacheSignature_NotFound(t *testing.T) {
 	ClearSignatureCache("")
 
-	// Non-existent cache entry
-	if got := GetCachedSignature("test-model", "some text"); got != "" {
-		t.Errorf("Expected empty string for missing entry, got '%s'", got)
+	// Non-existent session
+	if got := GetCachedSignature(testModelName, "some text"); got != "" {
+		t.Errorf("Expected empty string for nonexistent session, got '%s'", got)
 	}
 
-	// Existing cache but different text
-	CacheSignature("test-model", "text-a", "sigA12345678901234567890123456789012345678901234567890")
-	if got := GetCachedSignature("test-model", "text-b"); got != "" {
+	// Existing session but different text
+	CacheSignature(testModelName, "text-a", "sigA12345678901234567890123456789012345678901234567890")
+	if got := GetCachedSignature(testModelName, "text-b"); got != "" {
 		t.Errorf("Expected empty string for different text, got '%s'", got)
 	}
 }
@@ -58,11 +61,11 @@ func TestCacheSignature_EmptyInputs(t *testing.T) {
 	ClearSignatureCache("")
 
 	// All empty/invalid inputs should be no-ops
-	CacheSignature("test-model", "", "sig12345678901234567890123456789012345678901234567890")
-	CacheSignature("test-model", "text", "")
-	CacheSignature("test-model", "text", "short") // Too short
+	CacheSignature(testModelName, "", "sig12345678901234567890123456789012345678901234567890")
+	CacheSignature(testModelName, "text", "")
+	CacheSignature(testModelName, "text", "short") // Too short
 
-	if got := GetCachedSignature("test-model", "text"); got != "" {
+	if got := GetCachedSignature(testModelName, "text"); got != "" {
 		t.Errorf("Expected empty after invalid cache attempts, got '%s'", got)
 	}
 }
@@ -73,9 +76,9 @@ func TestCacheSignature_ShortSignatureRejected(t *testing.T) {
 	text := "Some text"
 	shortSig := "abc123" // Less than 50 chars
 
-	CacheSignature("test-model", text, shortSig)
+	CacheSignature(testModelName, text, shortSig)
 
-	if got := GetCachedSignature("test-model", text); got != "" {
+	if got := GetCachedSignature(testModelName, text); got != "" {
 		t.Errorf("Short signature should be rejected, got '%s'", got)
 	}
 }
@@ -83,18 +86,14 @@ func TestCacheSignature_ShortSignatureRejected(t *testing.T) {
 func TestClearSignatureCache_ModelGroup(t *testing.T) {
 	ClearSignatureCache("")
 
-	sigClaude := "validSig1234567890123456789012345678901234567890123456"
-	sigGpt := "validSig9876543210987654321098765432109876543210987654"
-	CacheSignature("claude-sonnet-4-5-thinking", "text", sigClaude)
-	CacheSignature("gpt-4o", "text", sigGpt)
+	sig := "validSig1234567890123456789012345678901234567890123456"
+	CacheSignature(testModelName, "text", sig)
+	CacheSignature(testModelName, "text-2", sig)
 
-	ClearSignatureCache("claude-sonnet-4-5-thinking")
+	ClearSignatureCache("session-1")
 
-	if got := GetCachedSignature("claude-sonnet-4-5-thinking", "text"); got != "" {
-		t.Error("Claude cache should be cleared")
-	}
-	if got := GetCachedSignature("gpt-4o", "text"); got != sigGpt {
-		t.Error("GPT cache should still exist")
+	if got := GetCachedSignature(testModelName, "text"); got != sig {
+		t.Error("signature should remain when clearing unknown session")
 	}
 }
 
@@ -102,35 +101,37 @@ func TestClearSignatureCache_AllSessions(t *testing.T) {
 	ClearSignatureCache("")
 
 	sig := "validSig1234567890123456789012345678901234567890123456"
-	CacheSignature("test-model", "text", sig)
-	CacheSignature("test-model", "text", sig)
+	CacheSignature(testModelName, "text", sig)
+	CacheSignature(testModelName, "text-2", sig)
 
 	ClearSignatureCache("")
 
-	if got := GetCachedSignature("test-model", "text"); got != "" {
-		t.Error("cache should be cleared")
+	if got := GetCachedSignature(testModelName, "text"); got != "" {
+		t.Error("text should be cleared")
 	}
-	if got := GetCachedSignature("test-model", "text"); got != "" {
-		t.Error("cache should be cleared")
+	if got := GetCachedSignature(testModelName, "text-2"); got != "" {
+		t.Error("text-2 should be cleared")
 	}
 }
 
 func TestHasValidSignature(t *testing.T) {
 	tests := []struct {
 		name      string
+		modelName string
 		signature string
 		expected  bool
 	}{
-		{"valid long signature", "abc123validSignature1234567890123456789012345678901234567890", true},
-		{"exactly 50 chars", "12345678901234567890123456789012345678901234567890", true},
-		{"49 chars - invalid", "1234567890123456789012345678901234567890123456789", false},
-		{"empty string", "", false},
-		{"short signature", "abc", false},
+		{"valid long signature", testModelName, "abc123validSignature1234567890123456789012345678901234567890", true},
+		{"exactly 50 chars", testModelName, "12345678901234567890123456789012345678901234567890", true},
+		{"49 chars - invalid", testModelName, "1234567890123456789012345678901234567890123456789", false},
+		{"empty string", testModelName, "", false},
+		{"short signature", testModelName, "abc", false},
+		{"gemini sentinel", "gemini-3-pro-preview", "skip_thought_signature_validator", true},
 	}
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			result := HasValidSignature("claude-sonnet-4-5-thinking", tt.signature)
+			result := HasValidSignature(tt.modelName, tt.signature)
 			if result != tt.expected {
 				t.Errorf("HasValidSignature(%q) = %v, expected %v", tt.signature, result, tt.expected)
 			}
@@ -147,13 +148,13 @@ func TestCacheSignature_TextHashCollisionResistance(t *testing.T) {
 	sig1 := "signature1_1234567890123456789012345678901234567890123456"
 	sig2 := "signature2_1234567890123456789012345678901234567890123456"
 
-	CacheSignature("test-model", text1, sig1)
-	CacheSignature("test-model", text2, sig2)
+	CacheSignature(testModelName, text1, sig1)
+	CacheSignature(testModelName, text2, sig2)
 
-	if GetCachedSignature("test-model", text1) != sig1 {
+	if GetCachedSignature(testModelName, text1) != sig1 {
 		t.Error("text1 signature mismatch")
 	}
-	if GetCachedSignature("test-model", text2) != sig2 {
+	if GetCachedSignature(testModelName, text2) != sig2 {
 		t.Error("text2 signature mismatch")
 	}
 }
@@ -164,9 +165,9 @@ func TestCacheSignature_UnicodeText(t *testing.T) {
 	text := "한글 텍스트와 이모지 🎉 그리고 特殊文字"
 	sig := "unicodeSig123456789012345678901234567890123456789012345"
 
-	CacheSignature("test-model", text, sig)
+	CacheSignature(testModelName, text, sig)
 
-	if got := GetCachedSignature("test-model", text); got != sig {
+	if got := GetCachedSignature(testModelName, text); got != sig {
 		t.Errorf("Unicode text signature retrieval failed, got '%s'", got)
 	}
 }
@@ -178,10 +179,10 @@ func TestCacheSignature_Overwrite(t *testing.T) {
 	sig1 := "firstSignature12345678901234567890123456789012345678901"
 	sig2 := "secondSignature1234567890123456789012345678901234567890"
 
-	CacheSignature("test-model", text, sig1)
-	CacheSignature("test-model", text, sig2) // Overwrite
+	CacheSignature(testModelName, text, sig1)
+	CacheSignature(testModelName, text, sig2) // Overwrite
 
-	if got := GetCachedSignature("test-model", text); got != sig2 {
+	if got := GetCachedSignature(testModelName, text); got != sig2 {
 		t.Errorf("Expected overwritten signature '%s', got '%s'", sig2, got)
 	}
 }
@@ -196,10 +197,10 @@ func TestCacheSignature_ExpirationLogic(t *testing.T) {
 	text := "text"
 	sig := "validSig1234567890123456789012345678901234567890123456"
 
-	CacheSignature("test-model", text, sig)
+	CacheSignature(testModelName, text, sig)
 
 	// Fresh entry should be retrievable
-	if got := GetCachedSignature("test-model", text); got != sig {
+	if got := GetCachedSignature(testModelName, text); got != sig {
 		t.Errorf("Fresh entry should be retrievable, got '%s'", got)
 	}
 

internal/runtime/executor/antigravity_executor.go

@@ -1214,6 +1214,17 @@ func (e *AntigravityExecutor) buildRequest(ctx context.Context, auth *cliproxyau
 		// const->enum conversion, and flattening of types/anyOf.
 		strJSON = util.CleanJSONSchemaForAntigravity(strJSON)
 
+		payload = []byte(strJSON)
+	} else {
+		strJSON := string(payload)
+		paths := make([]string, 0)
+		util.Walk(gjson.Parse(strJSON), "", "parametersJsonSchema", &paths)
+		for _, p := range paths {
+			strJSON, _ = util.RenameKey(strJSON, p, p[:len(p)-len("parametersJsonSchema")]+"parameters")
+		}
+		// Clean tool schemas for Gemini to remove unsupported JSON Schema keywords
+		// without adding empty-schema placeholders.
+		strJSON = util.CleanJSONSchemaForGemini(strJSON)
 		payload = []byte(strJSON)
 	}
 
@@ -1405,7 +1416,13 @@ func geminiToAntigravity(modelName string, payload []byte, projectID string) []b
 	template, _ = sjson.Set(template, "request.sessionId", generateStableSessionID(payload))
 
 	template, _ = sjson.Delete(template, "request.safetySettings")
-	//	template, _ = sjson.Set(template, "request.toolConfig.functionCallingConfig.mode", "VALIDATED")
+	if toolConfig := gjson.Get(template, "toolConfig"); toolConfig.Exists() && !gjson.Get(template, "request.toolConfig").Exists() {
+		template, _ = sjson.SetRaw(template, "request.toolConfig", toolConfig.Raw)
+		template, _ = sjson.Delete(template, "toolConfig")
+	}
+	if strings.Contains(modelName, "claude") {
+		template, _ = sjson.Set(template, "request.toolConfig.functionCallingConfig.mode", "VALIDATED")
+	}
 
 	if strings.Contains(modelName, "claude") || strings.Contains(modelName, "gemini-3-pro-high") {
 		gjson.Get(template, "request.tools").ForEach(func(key, tool gjson.Result) bool {

internal/util/gemini_schema.go

@@ -12,10 +12,99 @@ import (
 
 var gjsonPathKeyReplacer = strings.NewReplacer(".", "\\.", "*", "\\*", "?", "\\?")
 
+const placeholderReasonDescription = "Brief explanation of why you are calling this tool"
+
 // CleanJSONSchemaForAntigravity transforms a JSON schema to be compatible with Antigravity API.
 // It handles unsupported keywords, type flattening, and schema simplification while preserving
 // semantic information as description hints.
 func CleanJSONSchemaForAntigravity(jsonStr string) string {
+	return cleanJSONSchema(jsonStr, true)
+}
+
+func removeKeywords(jsonStr string, keywords []string) string {
+	for _, key := range keywords {
+		for _, p := range findPaths(jsonStr, key) {
+			if isPropertyDefinition(trimSuffix(p, "."+key)) {
+				continue
+			}
+			jsonStr, _ = sjson.Delete(jsonStr, p)
+		}
+	}
+	return jsonStr
+}
+
+// removePlaceholderFields removes placeholder-only properties ("_" and "reason") and their required entries.
+func removePlaceholderFields(jsonStr string) string {
+	// Remove "_" placeholder properties.
+	paths := findPaths(jsonStr, "_")
+	sortByDepth(paths)
+	for _, p := range paths {
+		if !strings.HasSuffix(p, ".properties._") {
+			continue
+		}
+		jsonStr, _ = sjson.Delete(jsonStr, p)
+		parentPath := trimSuffix(p, ".properties._")
+		reqPath := joinPath(parentPath, "required")
+		req := gjson.Get(jsonStr, reqPath)
+		if req.IsArray() {
+			var filtered []string
+			for _, r := range req.Array() {
+				if r.String() != "_" {
+					filtered = append(filtered, r.String())
+				}
+			}
+			if len(filtered) == 0 {
+				jsonStr, _ = sjson.Delete(jsonStr, reqPath)
+			} else {
+				jsonStr, _ = sjson.Set(jsonStr, reqPath, filtered)
+			}
+		}
+	}
+
+	// Remove placeholder-only "reason" objects.
+	reasonPaths := findPaths(jsonStr, "reason")
+	sortByDepth(reasonPaths)
+	for _, p := range reasonPaths {
+		if !strings.HasSuffix(p, ".properties.reason") {
+			continue
+		}
+		parentPath := trimSuffix(p, ".properties.reason")
+		props := gjson.Get(jsonStr, joinPath(parentPath, "properties"))
+		if !props.IsObject() || len(props.Map()) != 1 {
+			continue
+		}
+		desc := gjson.Get(jsonStr, p+".description").String()
+		if desc != placeholderReasonDescription {
+			continue
+		}
+		jsonStr, _ = sjson.Delete(jsonStr, p)
+		reqPath := joinPath(parentPath, "required")
+		req := gjson.Get(jsonStr, reqPath)
+		if req.IsArray() {
+			var filtered []string
+			for _, r := range req.Array() {
+				if r.String() != "reason" {
+					filtered = append(filtered, r.String())
+				}
+			}
+			if len(filtered) == 0 {
+				jsonStr, _ = sjson.Delete(jsonStr, reqPath)
+			} else {
+				jsonStr, _ = sjson.Set(jsonStr, reqPath, filtered)
+			}
+		}
+	}
+
+	return jsonStr
+}
+
+// CleanJSONSchemaForGemini transforms a JSON schema to be compatible with Gemini tool calling.
+// It removes unsupported keywords and simplifies schemas, without adding empty-schema placeholders.
+func CleanJSONSchemaForGemini(jsonStr string) string {
+	return cleanJSONSchema(jsonStr, false)
+}
+
+func cleanJSONSchema(jsonStr string, addPlaceholder bool) string {
 	// Phase 1: Convert and add hints
 	jsonStr = convertRefsToHints(jsonStr)
 	jsonStr = convertConstToEnum(jsonStr)
@@ -31,10 +120,16 @@ func CleanJSONSchemaForAntigravity(jsonStr string) string {
 
 	// Phase 3: Cleanup
 	jsonStr = removeUnsupportedKeywords(jsonStr)
+	if !addPlaceholder {
+		// Gemini schema cleanup: remove nullable/title and placeholder-only fields.
+		jsonStr = removeKeywords(jsonStr, []string{"nullable", "title"})
+		jsonStr = removePlaceholderFields(jsonStr)
+	}
 	jsonStr = cleanupRequiredFields(jsonStr)
-
 	// Phase 4: Add placeholder for empty object schemas (Claude VALIDATED mode requirement)
-	jsonStr = addEmptySchemaPlaceholder(jsonStr)
+	if addPlaceholder {
+		jsonStr = addEmptySchemaPlaceholder(jsonStr)
+	}
 
 	return jsonStr
 }
@@ -409,7 +504,7 @@ func addEmptySchemaPlaceholder(jsonStr string) string {
 			// Add placeholder "reason" property
 			reasonPath := joinPath(propsPath, "reason")
 			jsonStr, _ = sjson.Set(jsonStr, reasonPath+".type", "string")
-			jsonStr, _ = sjson.Set(jsonStr, reasonPath+".description", "Brief explanation of why you are calling this tool")
+			jsonStr, _ = sjson.Set(jsonStr, reasonPath+".description", placeholderReasonDescription)
 
 			// Add to required array
 			jsonStr, _ = sjson.Set(jsonStr, reqPath, []string{"reason"})