Fixed: #551

fix(translator): standardize content node handling across translators for assistant and tool calls

internal/translator/antigravity/openai/chat-completions/antigravity_openai_request.go

@@ -222,17 +222,17 @@ func ConvertOpenAIRequestToAntigravity(modelName string, inputRawJSON []byte, _
 				}
 				out, _ = sjson.SetRawBytes(out, "request.contents.-1", node)
 			} else if role == "assistant" {
+				node := []byte(`{"role":"model","parts":[]}`)
+				p := 0
 				if content.Type == gjson.String {
-					// Assistant text -> single model content
+					node, _ = sjson.SetBytes(node, "parts.-1.text", content.String())
-					node := []byte(`{"role":"model","parts":[{"text":""}]}`)
-					node, _ = sjson.SetBytes(node, "parts.0.text", content.String())
 					out, _ = sjson.SetRawBytes(out, "request.contents.-1", node)
-				} else if !content.Exists() || content.Type == gjson.Null {
+					p++
+				}
+
 				// Tool calls -> single model content with functionCall parts
 				tcs := m.Get("tool_calls")
 				if tcs.IsArray() {
-						node := []byte(`{"role":"model","parts":[]}`)
-						p := 0
 					fIDs := make([]string, 0)
 					for _, tc := range tcs.Array() {
 						if tc.Get("type").String() != "function" {
@@ -282,7 +282,6 @@ func ConvertOpenAIRequestToAntigravity(modelName string, inputRawJSON []byte, _
 			}
 		}
 	}
-	}
 
 	// tools -> request.tools[0].functionDeclarations + request.tools[0].googleSearch passthrough
 	tools := gjson.GetBytes(rawJSON, "tools")
@@ -361,18 +360,3 @@ func ConvertOpenAIRequestToAntigravity(modelName string, inputRawJSON []byte, _
 
 // itoa converts int to string without strconv import for few usages.
 func itoa(i int) string { return fmt.Sprintf("%d", i) }
-
-// quoteIfNeeded ensures a string is valid JSON value (quotes plain text), pass-through for JSON objects/arrays.
-func quoteIfNeeded(s string) string {
-	s = strings.TrimSpace(s)
-	if s == "" {
-		return "\"\""
-	}
-	if len(s) > 0 && (s[0] == '{' || s[0] == '[') {
-		return s
-	}
-	// escape quotes minimally
-	s = strings.ReplaceAll(s, "\\", "\\\\")
-	s = strings.ReplaceAll(s, "\"", "\\\"")
-	return "\"" + s + "\""
-}

internal/translator/gemini-cli/openai/chat-completions/gemini-cli_openai_request.go

@@ -205,17 +205,18 @@ func ConvertOpenAIRequestToGeminiCLI(modelName string, inputRawJSON []byte, _ bo
 				}
 				out, _ = sjson.SetRawBytes(out, "request.contents.-1", node)
 			} else if role == "assistant" {
+				p := 0
+				node := []byte(`{"role":"model","parts":[]}`)
 				if content.Type == gjson.String {
 					// Assistant text -> single model content
-					node := []byte(`{"role":"model","parts":[{"text":""}]}`)
+					node, _ = sjson.SetBytes(node, "parts.-1.text", content.String())
-					node, _ = sjson.SetBytes(node, "parts.0.text", content.String())
 					out, _ = sjson.SetRawBytes(out, "request.contents.-1", node)
-				} else if !content.Exists() || content.Type == gjson.Null {
+					p++
+				}
+
 				// Tool calls -> single model content with functionCall parts
 				tcs := m.Get("tool_calls")
 				if tcs.IsArray() {
-						node := []byte(`{"role":"model","parts":[]}`)
-						p := 0
 					fIDs := make([]string, 0)
 					for _, tc := range tcs.Array() {
 						if tc.Get("type").String() != "function" {
@@ -255,7 +256,6 @@ func ConvertOpenAIRequestToGeminiCLI(modelName string, inputRawJSON []byte, _ bo
 			}
 		}
 	}
-	}
 
 	// tools -> request.tools[0].functionDeclarations + request.tools[0].googleSearch passthrough
 	tools := gjson.GetBytes(rawJSON, "tools")
@@ -334,18 +334,3 @@ func ConvertOpenAIRequestToGeminiCLI(modelName string, inputRawJSON []byte, _ bo
 
 // itoa converts int to string without strconv import for few usages.
 func itoa(i int) string { return fmt.Sprintf("%d", i) }
-
-// quoteIfNeeded ensures a string is valid JSON value (quotes plain text), pass-through for JSON objects/arrays.
-func quoteIfNeeded(s string) string {
-	s = strings.TrimSpace(s)
-	if s == "" {
-		return "\"\""
-	}
-	if len(s) > 0 && (s[0] == '{' || s[0] == '[') {
-		return s
-	}
-	// escape quotes minimally
-	s = strings.ReplaceAll(s, "\\", "\\\\")
-	s = strings.ReplaceAll(s, "\"", "\\\"")
-	return "\"" + s + "\""
-}

internal/translator/gemini/openai/chat-completions/gemini_openai_request.go

@@ -207,15 +207,16 @@ func ConvertOpenAIRequestToGemini(modelName string, inputRawJSON []byte, _ bool)
 				}
 				out, _ = sjson.SetRawBytes(out, "contents.-1", node)
 			} else if role == "assistant" {
-				if content.Type == gjson.String {
-					// Assistant text -> single model content
-					node := []byte(`{"role":"model","parts":[{"text":""}]}`)
-					node, _ = sjson.SetBytes(node, "parts.0.text", content.String())
-					out, _ = sjson.SetRawBytes(out, "contents.-1", node)
-				} else if content.IsArray() {
-					// Assistant multimodal content (e.g. text + image) -> single model content with parts
 				node := []byte(`{"role":"model","parts":[]}`)
 				p := 0
+
+				if content.Type == gjson.String {
+					// Assistant text -> single model content
+					node, _ = sjson.SetBytes(node, "parts.-1.text", content.String())
+					out, _ = sjson.SetRawBytes(out, "contents.-1", node)
+					p++
+				} else if content.IsArray() {
+					// Assistant multimodal content (e.g. text + image) -> single model content with parts
 					for _, item := range content.Array() {
 						switch item.Get("type").String() {
 						case "text":
@@ -237,12 +238,11 @@ func ConvertOpenAIRequestToGemini(modelName string, inputRawJSON []byte, _ bool)
 						}
 					}
 					out, _ = sjson.SetRawBytes(out, "contents.-1", node)
-				} else if !content.Exists() || content.Type == gjson.Null {
+				}
+
 				// Tool calls -> single model content with functionCall parts
 				tcs := m.Get("tool_calls")
 				if tcs.IsArray() {
-						node := []byte(`{"role":"model","parts":[]}`)
-						p := 0
 					fIDs := make([]string, 0)
 					for _, tc := range tcs.Array() {
 						if tc.Get("type").String() != "function" {
@@ -282,7 +282,6 @@ func ConvertOpenAIRequestToGemini(modelName string, inputRawJSON []byte, _ bool)
 			}
 		}
 	}
-	}
 
 	// tools -> tools[0].functionDeclarations + tools[0].googleSearch passthrough
 	tools := gjson.GetBytes(rawJSON, "tools")
@@ -363,18 +362,3 @@ func ConvertOpenAIRequestToGemini(modelName string, inputRawJSON []byte, _ bool)
 
 // itoa converts int to string without strconv import for few usages.
 func itoa(i int) string { return fmt.Sprintf("%d", i) }
-
-// quoteIfNeeded ensures a string is valid JSON value (quotes plain text), pass-through for JSON objects/arrays.
-func quoteIfNeeded(s string) string {
-	s = strings.TrimSpace(s)
-	if s == "" {
-		return "\"\""
-	}
-	if len(s) > 0 && (s[0] == '{' || s[0] == '[') {
-		return s
-	}
-	// escape quotes minimally
-	s = strings.ReplaceAll(s, "\\", "\\\\")
-	s = strings.ReplaceAll(s, "\"", "\\\"")
-	return "\"" + s + "\""
-}