diff --git a/backend/migrations/004_user_scenarios.up.sql b/backend/migrations/004_user_scenarios.up.sql
index 1fc8870..66cb7ad 100644
--- a/backend/migrations/004_user_scenarios.up.sql
+++ b/backend/migrations/004_user_scenarios.up.sql
@@ -6,7 +6,7 @@ CREATE TABLE user_scenarios (
     user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
     name VARCHAR(50) NOT NULL,
     icon VARCHAR(10) DEFAULT '✨',
-    description VARCHAR(100) NOT NULL,
+    description VARCHAR(100),
     prompt TEXT NOT NULL,
     greeting VARCHAR(200),
     language VARCHAR(10) DEFAULT 'zh-CN',
@@ -15,8 +15,8 @@ CREATE TABLE user_scenarios (
 
     CONSTRAINT unique_user_scenario UNIQUE(user_id, name),
     CONSTRAINT check_name_length CHECK (char_length(name) >= 2 AND char_length(name) <= 50),
-    CONSTRAINT check_description_length CHECK (char_length(description) >= 5 AND char_length(description) <= 100),
-    CONSTRAINT check_prompt_length CHECK (char_length(prompt) >= 50 AND char_length(prompt) <= 2000)
+    CONSTRAINT check_description_length CHECK (description IS NULL OR (char_length(description) >= 1 AND char_length(description) <= 100)),
+    CONSTRAINT check_prompt_length CHECK (char_length(prompt) >= 10 AND char_length(prompt) <= 2000)
 );
 
 -- 为用户 ID 创建索引，加速查询
@@ -30,7 +30,7 @@ COMMENT ON COLUMN user_scenarios.id IS '情景唯一标识';
 COMMENT ON COLUMN user_scenarios.user_id IS '所属用户 ID，外键关联 users 表';
 COMMENT ON COLUMN user_scenarios.name IS '情景名称，如"创意写作导师"';
 COMMENT ON COLUMN user_scenarios.icon IS 'Emoji 图标，如"🎨"';
-COMMENT ON COLUMN user_scenarios.description IS '简短描述，显示在情景卡片上';
+COMMENT ON COLUMN user_scenarios.description IS '简短描述，可选，显示在情景卡片上';
 COMMENT ON COLUMN user_scenarios.prompt IS '角色 System Prompt，定义 AI 行为';
 COMMENT ON COLUMN user_scenarios.greeting IS '首句引导，可选';
 COMMENT ON COLUMN user_scenarios.language IS '默认语言，如 zh-CN、en-US';