diff --git a/src/modal.ts b/src/modal.ts
index 55f088c..fa210de 100644
--- a/src/modal.ts
+++ b/src/modal.ts
@@ -1,6 +1,6 @@
 'use strict';
 
-import { Modal } from 'obsidian';
+import { type App, Modal } from 'obsidian';
 import type { CardPatch, PluginHost, ResolvedCard } from './types';
 import { addTextButton } from './ui-helpers';
 
@@ -9,7 +9,7 @@ export class CardEditModal extends Modal {
   card: ResolvedCard;
   onSave: (patch: CardPatch) => void | Promise<void>;
 
-  constructor(app, plugin: PluginHost, card: ResolvedCard, onSave: (patch: CardPatch) => void | Promise<void>) {
+  constructor(app: App, plugin: PluginHost, card: ResolvedCard, onSave: (patch: CardPatch) => void | Promise<void>) {
     super(app);
     this.plugin = plugin;
     this.card = card || ({} as ResolvedCard);
diff --git a/src/settings-tab.ts b/src/settings-tab.ts
index 39d5134..c5c83ee 100644
--- a/src/settings-tab.ts
+++ b/src/settings-tab.ts
@@ -1,6 +1,6 @@
 'use strict';
 
-import { Notice, PluginSettingTab, requestUrl, Setting } from 'obsidian';
+import { type App, Notice, type Plugin, PluginSettingTab, requestUrl, Setting } from 'obsidian';
 import { resolveCliPath, runCli } from './cli';
 import { testApiBackend } from './providers';
 import {
@@ -36,10 +36,10 @@ async function testBackend(settings) {
 }
 
 export class ParallelReaderSettingTab extends PluginSettingTab {
-  plugin: PluginHost;
+  plugin: Plugin & PluginHost;
 
-  constructor(app, plugin: PluginHost) {
-    super(app, plugin as any);
+  constructor(app: App, plugin: Plugin & PluginHost) {
+    super(app, plugin);
     this.plugin = plugin;
   }
 
diff --git a/src/types.ts b/src/types.ts
index 4bf566b..d6c9de5 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -1,5 +1,7 @@
 'use strict';
 
+import type { App, PluginManifest, TFile } from 'obsidian';
+
 /* ---------- Card types ---------- */
 
 /** Raw card as returned by the LLM and stored in cache (no computed fields). */
@@ -114,16 +116,16 @@ export interface PromptPair {
  * main.ts and the extracted modules.
  */
 export interface PluginHost {
-  app: { vault: any; workspace: any };
+  app: App;
   settings: PluginSettings;
   cache: Record<string, CacheEntry>;
-  manifest?: { id: string };
+  manifest: PluginManifest;
   t(key: string, vars?: Record<string, string | number>): string;
-  isGeneratingFile(file: any): boolean;
-  cancelGenerationForFile(file: any): boolean;
-  runForFile(file: any, force: boolean): Promise<void>;
+  isGeneratingFile(file: TFile | null): boolean;
+  cancelGenerationForFile(file: TFile | null): boolean;
+  runForFile(file: TFile | null, force: boolean): Promise<void>;
   copyCurrentViewMarkdown(): Promise<void>;
-  scrollEditorToLine(line: number, file: any): Promise<void>;
+  scrollEditorToLine(line: number, file: TFile | null): Promise<void>;
   cacheReplaceCards(filePath: string, cards: ResolvedCard[]): Promise<boolean>;
   saveSettings(): Promise<void>;
   saveSettingsDebounced(delayMs?: number): void;
diff --git a/src/vault.ts b/src/vault.ts
index 660573c..8e96783 100644
--- a/src/vault.ts
+++ b/src/vault.ts
@@ -1,6 +1,8 @@
 'use strict';
 
-export function normalizeVaultPath(path) {
+import type { App } from 'obsidian';
+
+export function normalizeVaultPath(path: string): string {
   return String(path || '')
     .split('/')
     .map((part) => part.trim())
@@ -8,14 +10,14 @@ export function normalizeVaultPath(path) {
     .join('/');
 }
 
-export function folderPathsForTarget(folderPath) {
+export function folderPathsForTarget(folderPath: string): string[] {
   const normalized = normalizeVaultPath(folderPath);
   if (!normalized) return [];
   const parts = normalized.split('/');
   return parts.map((_, idx) => parts.slice(0, idx + 1).join('/'));
 }
 
-export async function ensureVaultFolder(app, folderPath) {
+export async function ensureVaultFolder(app: App, folderPath: string) {
   for (const folder of folderPathsForTarget(folderPath)) {
     if (app.vault.getAbstractFileByPath(folder)) continue;
     try {