diff --git a/ai-service/scripts/migrations/007_add_field_roles_and_slot_definitions.sql b/ai-service/scripts/migrations/007_add_field_roles_and_slot_definitions.sql
new file mode 100644
index 0000000..1c7f404
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+++ b/ai-service/scripts/migrations/007_add_field_roles_and_slot_definitions.sql
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+-- Migration: Add field_roles and slot_definitions
+-- Date: 2026-03-05
+-- Issue: [AC-MRS-01, AC-MRS-07] 元数据职责分层优化
+
+-- 1. 为 metadata_field_definitions 表新增 field_roles 字段
+ALTER TABLE metadata_field_definitions 
+ADD COLUMN IF NOT EXISTS field_roles JSONB DEFAULT '[]'::jsonb;
+
+-- 2. 创建 GIN 索引支持按角色查询
+CREATE INDEX IF NOT EXISTS idx_metadata_field_definitions_roles 
+ON metadata_field_definitions USING GIN (field_roles);
+
+-- 3. 添加字段注释
+COMMENT ON COLUMN metadata_field_definitions.field_roles IS 
+'[AC-MRS-01] 字段角色列表：resource_filter, slot, prompt_var, routing_signal';
+
+-- 4. 创建 slot_definitions 表
+CREATE TABLE IF NOT EXISTS slot_definitions (
+    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    tenant_id VARCHAR NOT NULL,
+    slot_key VARCHAR(100) NOT NULL,
+    type VARCHAR(20) NOT NULL DEFAULT 'string',
+    required BOOLEAN NOT NULL DEFAULT FALSE,
+    extract_strategy VARCHAR(20),
+    validation_rule TEXT,
+    ask_back_prompt TEXT,
+    default_value JSONB,
+    linked_field_id UUID REFERENCES metadata_field_definitions(id),
+    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
+    
+    CONSTRAINT uk_slot_definitions_tenant_key UNIQUE (tenant_id, slot_key),
+    CONSTRAINT chk_slot_definitions_type CHECK (type IN ('string', 'number', 'boolean', 'enum', 'array_enum')),
+    CONSTRAINT chk_slot_definitions_extract_strategy CHECK (extract_strategy IS NULL OR extract_strategy IN ('rule', 'llm', 'user_input'))
+);
+
+-- 5. 创建索引
+CREATE INDEX IF NOT EXISTS ix_slot_definitions_tenant 
+ON slot_definitions(tenant_id);
+
+CREATE INDEX IF NOT EXISTS ix_slot_definitions_tenant_key 
+ON slot_definitions(tenant_id, slot_key);
+
+CREATE INDEX IF NOT EXISTS ix_slot_definitions_linked_field 
+ON slot_definitions(linked_field_id);
+
+-- 6. 添加表和字段注释
+COMMENT ON TABLE slot_definitions IS '[AC-MRS-07] 槽位定义表';
+COMMENT ON COLUMN slot_definitions.slot_key IS '[AC-MRS-07] 槽位键名，可与元数据字段 field_key 关联';
+COMMENT ON COLUMN slot_definitions.type IS '[AC-MRS-07] 槽位类型：string/number/boolean/enum/array_enum';
+COMMENT ON COLUMN slot_definitions.required IS '[AC-MRS-07] 是否必填槽位';
+COMMENT ON COLUMN slot_definitions.extract_strategy IS '[AC-MRS-07] 提取策略：rule/llm/user_input';
+COMMENT ON COLUMN slot_definitions.validation_rule IS '[AC-MRS-07] 校验规则（正则或 JSON Schema）';
+COMMENT ON COLUMN slot_definitions.ask_back_prompt IS '[AC-MRS-07] 追问提示语模板';
+COMMENT ON COLUMN slot_definitions.default_value IS '[AC-MRS-07] 默认值';
+COMMENT ON COLUMN slot_definitions.linked_field_id IS '[AC-MRS-08] 关联的元数据字段 ID';
+
+-- 7. 初始化现有字段的默认角色（根据 is_filterable 推断 resource_filter 角色）
+UPDATE metadata_field_definitions 
+SET field_roles = '["resource_filter"]'::jsonb
+WHERE is_filterable = true 
+  AND status = 'active'
+  AND (field_roles IS NULL OR field_roles = '[]'::jsonb);