fix: normalize LLM output types in profile serialization

backend/app/services/oasis_profile_generator.py

@@ -25,6 +25,47 @@
 logger = get_logger('mirofish.oasis_profile')
 
 
+def _coerce_to_str(value: Any) -> str:
+    """Coerce a value to a plain string.
+
+    Handles dict, list, and other non-string types that may be returned
+    by LLM JSON parsing.
+    """
+    if isinstance(value, str):
+        return value
+    if isinstance(value, dict):
+        for key in ('text', 'value', 'description', 'content', 'summary', 'name'):
+            if key in value and isinstance(value[key], str):
+                return value[key]
+        return json.dumps(value, ensure_ascii=False)
+    if isinstance(value, list):
+        str_items = [_coerce_to_str(item) for item in value]
+        return ', '.join(str_items)
+    return str(value)
+
+
+def _coerce_to_str_list(value: Any) -> List[str]:
+    """Coerce a value to a list of strings.
+
+    Handles nested structures that may be returned by LLM JSON parsing.
+    """
+    if isinstance(value, list):
+        result = []
+        for item in value:
+            if isinstance(item, str):
+                result.append(item)
+            elif isinstance(item, dict):
+                result.append(_coerce_to_str(item))
+            else:
+                result.append(str(item))
+        return result
+    if isinstance(value, str):
+        return [value]
+    if isinstance(value, dict):
+        return [_coerce_to_str(value)]
+    return []
+
+
 @dataclass
 class OasisAgentProfile:
     """OASIS Agent Profile数据结构"""
@@ -57,6 +98,16 @@ class OasisAgentProfile:
 
     created_at: str = field(default_factory=lambda: datetime.now().strftime("%Y-%m-%d"))
 
+    def __post_init__(self):
+        """Normalize field types to guard against structured LLM outputs
+        (e.g. dict/list instead of plain strings)."""
+        self.bio = _coerce_to_str(self.bio)
+        self.persona = _coerce_to_str(self.persona)
+        self.country = _coerce_to_str(self.country) if self.country is not None else None
+        self.profession = _coerce_to_str(self.profession) if self.profession is not None else None
+        self.gender = _coerce_to_str(self.gender) if self.gender is not None else None
+        self.interested_topics = _coerce_to_str_list(self.interested_topics)
+
     def to_reddit_format(self) -> Dict[str, Any]:
         """转换为Reddit平台格式"""
         profile = {
@@ -549,6 +600,15 @@ def _generate_profile_with_llm(
                 try:
                     result = json.loads(content)
 
+                    # Normalize types from LLM output
+                    for str_field in ('bio', 'persona', 'country', 'profession'):
+                        if str_field in result and result[str_field] is not None:
+                            result[str_field] = _coerce_to_str(result[str_field])
+                    if 'interested_topics' in result:
+                        result['interested_topics'] = _coerce_to_str_list(
+                            result['interested_topics']
+                        )
+
                     # 验证必需字段
                     if "bio" not in result or not result["bio"]:
                         result["bio"] = entity_summary[:200] if entity_summary else f"{entity_type}: {entity_name}"
@@ -1092,15 +1152,19 @@ def _save_twitter_csv(self, profiles: List[OasisAgentProfile], file_path: str):
 
             # 写入数据行
             for idx, profile in enumerate(profiles):
+                # Defensive coercion in case __post_init__ was bypassed
+                bio = _coerce_to_str(profile.bio) if profile.bio else profile.name
+                persona = _coerce_to_str(profile.persona) if profile.persona else ''
+
                 # user_char: 完整人设（bio + persona），用于LLM系统提示
-                user_char = profile.bio
-                if profile.persona and profile.persona != profile.bio:
-                    user_char = f"{profile.bio} {profile.persona}"
+                user_char = bio
+                if persona and persona != bio:
+                    user_char = f"{bio} {persona}"
                 # 处理换行符（CSV中用空格替代）
                 user_char = user_char.replace('\n', ' ').replace('\r', ' ')
 
                 # description: 简短简介，用于外部显示
-                description = profile.bio.replace('\n', ' ').replace('\r', ' ')
+                description = bio.replace('\n', ' ').replace('\r', ' ')
 
                 row = [
                     idx,                    # user_id: 从0开始的顺序ID
@@ -1158,27 +1222,40 @@ def _save_reddit_json(self, profiles: List[OasisAgentProfile], file_path: str):
         """
         data = []
         for idx, profile in enumerate(profiles):
+            # Defensive coercion in case __post_init__ was bypassed
+            bio = _coerce_to_str(profile.bio) if profile.bio else f"{profile.name}"
+            persona = _coerce_to_str(profile.persona) if profile.persona else (
+                f"{profile.name} is a participant in social discussions."
+            )
+            country = _coerce_to_str(profile.country) if profile.country else "中国"
+            profession = _coerce_to_str(profile.profession) if profile.profession else None
+            interested_topics = (
+                _coerce_to_str_list(profile.interested_topics)
+                if profile.interested_topics
+                else None
+            )
+
             # 使用与 to_reddit_format() 一致的格式
             item = {
                 "user_id": profile.user_id if profile.user_id is not None else idx,  # 关键：必须包含 user_id
                 "username": profile.user_name,
                 "name": profile.name,
-                "bio": profile.bio[:150] if profile.bio else f"{profile.name}",
-                "persona": profile.persona or f"{profile.name} is a participant in social discussions.",
+                "bio": bio[:150],
+                "persona": persona,
                 "karma": profile.karma if profile.karma else 1000,
                 "created_at": profile.created_at,
                 # OASIS必需字段 - 确保都有默认值
                 "age": profile.age if profile.age else 30,
                 "gender": self._normalize_gender(profile.gender),
                 "mbti": profile.mbti if profile.mbti else "ISTJ",
-                "country": profile.country if profile.country else "中国",
+                "country": country,
             }
 
             # 可选字段
-            if profile.profession:
-                item["profession"] = profile.profession
-            if profile.interested_topics:
-                item["interested_topics"] = profile.interested_topics
+            if profession:
+                item["profession"] = profession
+            if interested_topics:
+                item["interested_topics"] = interested_topics
 
             data.append(item)