diff --git a/scrapbox.d.ts b/scrapbox.d.ts
new file mode 100644
index 0000000..d06a398
--- /dev/null
+++ b/scrapbox.d.ts
@@ -0,0 +1,130 @@
+export type Layout =
+  | "list"
+  | "page"
+  | "stream"
+  | "project-settings-billing-page"
+  | "project-settings-basic-page"
+  | "project-settings-members-page"
+  | "settings-profile-page"
+  | "settings-extensions-page"
+  | "settings-delete-account-page";
+export type Scrapbox =
+  & {
+    Project: {
+      name: string;
+      pages: PageBrief[];
+    };
+    TimeStamp: TimeStamp;
+    PopupMenu?: {
+      addButton: (
+        props: {
+          title: string | ((selectedText: string) => string);
+          onClick: (selectedText: string) => string | undefined;
+        },
+      ) => void;
+    };
+    PageMenu: ((name: string) => PageMenu) & {
+      addMenu: (
+        props: { title: string; image: string; onClick?: () => void },
+      ) => void;
+      addItem: (props: AddItemProps) => void;
+      addSeparator: () => void;
+      removeAllItems: () => void;
+    };
+    addListener: (type: string, listener: () => void) => void;
+    on: (type: string, listener: () => void) => void;
+    removeListener: (type: string, listener: () => void) => void;
+    off: (type: string, listener: () => void) => void;
+    removeAllListeners: (type?: string) => void;
+    once: (type: string, listener: () => void) => void;
+    prependListener: (type: string, listener: () => void) => void;
+    prependOnceListener: (type: string, listener: () => void) => void;
+    listeners: (type: string) => (() => void)[];
+    rawListeners: (type: string) => (() => void)[];
+    listenerCount: (type: string) => number;
+    emit: (type: string) => void;
+    eventNames: () => string[];
+    getMexListeners: () => number;
+    setMexListeners: (length: number) => void;
+  }
+  & ({
+    Layout:
+      | "list"
+      | "stream"
+      | "project-settings-billing-page"
+      | "project-settings-basic-page"
+      | "project-settings-members-page"
+      | "settings-profile-page"
+      | "settings-extensions-page"
+      | "settings-delete-account-page";
+    Page: {
+      title: null;
+      lines: null;
+      id: null;
+    };
+  } | {
+    Layout: "page";
+    Page: {
+      title: string;
+      lines: ParsedLine[];
+      id: string;
+    };
+  });
+
+export type PageBrief = {
+  exists: boolean;
+  hasIcon?: boolean;
+  id: string;
+  title: string;
+  titleLc: string;
+  updated: number;
+};
+
+export type ParsedLine = {
+  text: string;
+  id: string;
+  userId: string;
+  updated: number;
+  created: number;
+  section: {
+    number: number;
+    start: boolean;
+    end: boolean;
+  };
+  title?: boolean;
+};
+
+type TimeStamp = {
+  addFormat: (format: string | (() => string)) => void;
+  removeAllFormat: () => void;
+};
+
+type AddItemProps = {
+  title: string | (() => string);
+  image?: string;
+  onClick: () => void;
+};
+type PageMenu = {
+  addItem: (
+    props: AddItemProps,
+  ) => void;
+  addSeparator: () => void;
+  removeAllItems: () => void;
+  menuName: string;
+  reset: () => void;
+  emitChange: () => void;
+  menus: Map<
+    string,
+    {
+      image: string | null;
+      onClick?: () => void;
+      items: (AddItemProps & { separator: boolean })[];
+    }
+  >;
+};
+
+export type eventName =
+  | "lines:changed"
+  | "page:changed"
+  | "layout:changed"
+  | "project:changed";