diff --git a/doc/architecure/song-type.md b/doc/architecure/song-type.md
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+# Song Type
+
+The Unrelated type refers specifically to videos that are not in our [Scope of Inclusion](../about/scope-of-inclusion).
+
+## Table: `songs`
+
+The `type` column used in the `songs` table.
+
+| Type | Description            |
+| ---- | ---------------------- |
+| 0    | Unrelated              |
+| 1    | Original               |
+| 2    | Cover                  |
+| 3    | Remix                  |
+| 4    | Instrumental           |
+| 10   | Others                 |
+
+## Table: `labelling_result`
+
+| Label | Description            |
+| ----- | ---------------------- |
+|   0   | AI tagged: Unrelated   |
+|   1   | AI tagged: Original    |
+|   2   | AI tagged: Cover/Remix |
diff --git a/doc/include_instruction.md b/doc/include_instruction.md
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-# 收录规则
-
-**这是一份实验性质
diff --git a/doc/song_type.md b/doc/song_type.md
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-# Song Type
-
-The `type` column used in the PostgreSQL database.
-
-| Type | Description            |
-| ---- | ---------------------- |
-| 0    | Other                  |
-| 1    | Original               |
-| 2    | Cover                  |
-| 3    | Remix                  |
-| 4    | Instrumental           |
-| 100  | AI tagged: Unrelated   |
-| 101  | AI tagged: Original    |
-| 102  | AI tagged: Cover/Remix |