diff --git a/packages/discloud.app/src/managers/AppAptManager.ts b/packages/discloud.app/src/managers/AppAptManager.ts
index d4a289556..5613642c6 100644
--- a/packages/discloud.app/src/managers/AppAptManager.ts
+++ b/packages/discloud.app/src/managers/AppAptManager.ts
@@ -1,6 +1,6 @@
 import { Routes, type APTString, type RESTDeleteApiAppAptResult, type RESTPutApiAppAptResult } from "@discloudapp/api-types/v2";
-import z from "zod";
 import type DiscloudApp from "../discloudApp/DiscloudApp";
+import { validateNonEmptyString } from "../util/assertions";
 import BaseManager from "./BaseManager";
 
 /**
@@ -18,7 +18,7 @@ export default class AppAptManager extends BaseManager {
    * @param apt - One or more APTs to install. See {@link AptString}.
    */
   async install(appID: string, apt: APTString | APTString[]): Promise<RESTPutApiAppAptResult> {
-    z.string().parse(appID);
+    validateNonEmptyString(appID);
 
     if (Array.isArray(apt)) apt = <APTString>apt.join();
 
@@ -34,7 +34,7 @@ export default class AppAptManager extends BaseManager {
    * @param apt - One or more APTs to uninstall. See {@link AptString}.
    */
   async uninstall(appID: string, apt: APTString | APTString[]): Promise<RESTDeleteApiAppAptResult> {
-    z.string().parse(appID);
+    validateNonEmptyString(appID);
 
     if (Array.isArray(apt)) apt = <APTString>apt.join();
 
diff --git a/packages/discloud.app/src/managers/AppManager.ts b/packages/discloud.app/src/managers/AppManager.ts
index e95995065..21318c570 100644
--- a/packages/discloud.app/src/managers/AppManager.ts
+++ b/packages/discloud.app/src/managers/AppManager.ts
@@ -2,13 +2,13 @@ import { Routes, type ApiAppManagerRemovedAll, type ApiAppManagerRestartedAll, t
 import { DiscloudAPIError } from "@discloudapp/rest";
 import { resolveFile } from "@discloudapp/util";
 import { constants } from "http2";
-import z from "zod";
 import { ProfileOptions, type CreateAppOptions, type UpdateAppOptions } from "../@types";
 import type DiscloudApp from "../discloudApp/DiscloudApp";
 import App from "../structures/App";
 import AppBackup from "../structures/AppBackup";
 import type AppStatus from "../structures/AppStatus";
 import AppUploaded from "../structures/AppUploaded";
+import { validateNonEmptyString, validateNumberType } from "../util/assertions";
 import CachedManager from "./CachedManager";
 
 /**
@@ -26,6 +26,8 @@ export default class AppManager extends CachedManager<typeof App> {
    */
   async status(appID: string): Promise<AppStatus>
   async status(appID: string) {
+    validateNonEmptyString(appID);
+
     const data = await this.discloudApp.rest.get<RESTGetApiAppStatusResult>(Routes.appStatus(appID));
 
     return this._add(data.apps).status;
@@ -38,6 +40,9 @@ export default class AppManager extends CachedManager<typeof App> {
    * @param command - The command
    */
   async console(appID: string, command: string): Promise<ApiConsoleAppShell> {
+    validateNonEmptyString(appID);
+    validateNonEmptyString(command);
+
     const data = await this.discloudApp.rest.put<RESTPutApiAppConsoleResult>(Routes.appConsole(appID), {
       body: { command },
     });
@@ -51,8 +56,10 @@ export default class AppManager extends CachedManager<typeof App> {
    * @param appID - Your app id
    */
   async terminal(appID: string): Promise<ApiTerminal>
-  async terminal(appID?: "all"): Promise<Map<string, ApiTerminal>>
-  async terminal(appID = "all") {
+  async terminal(appID: "all"): Promise<Map<string, ApiTerminal>>
+  async terminal(appID: string) {
+    validateNonEmptyString(appID);
+
     const data = await this.discloudApp.rest.get<
       | RESTGetApiAppLogResult
       | RESTGetApiAppAllLogResult
@@ -77,8 +84,10 @@ export default class AppManager extends CachedManager<typeof App> {
    * @param appID - Your app id
    */
   async backup(appID: string): Promise<AppBackup>
-  async backup(appID?: "all"): Promise<Map<string, AppBackup>>
-  async backup(appID = "all") {
+  async backup(appID: "all"): Promise<Map<string, AppBackup>>
+  async backup(appID: string) {
+    validateNonEmptyString(appID);
+
     const data = await this.discloudApp.rest.get<
       | RESTGetApiAppBackupResult
       | RESTGetApiAppAllBackupResult
@@ -104,8 +113,8 @@ export default class AppManager extends CachedManager<typeof App> {
    * @param quantity - Minimum values is `100` to `bot` or `512` for `site`
    */
   async ram(appID: string, quantity: number) {
-    z.string().parse(appID);
-    z.number().min(100).parse(quantity);
+    validateNonEmptyString(appID);
+    validateNumberType(quantity);
 
     const data = await this.discloudApp.rest.put<RESTPutApiAppRamResult>(Routes.appRam(appID), {
       body: {
@@ -150,7 +159,7 @@ export default class AppManager extends CachedManager<typeof App> {
    * @param options - Options to update your app.
    */
   async update(appID: string, options: UpdateAppOptions) {
-    z.string().parse(appID);
+    validateNonEmptyString(appID);
 
     options.file = await resolveFile(options.file);
 
@@ -167,8 +176,10 @@ export default class AppManager extends CachedManager<typeof App> {
    * @param appID - Your app id
    */
   async delete(appID: string): Promise<RESTDeleteApiAppDeleteResult>
-  async delete(appID?: "all"): Promise<ApiAppManagerRemovedAll>
-  async delete(appID = "all") {
+  async delete(appID: "all"): Promise<ApiAppManagerRemovedAll>
+  async delete(appID: string) {
+    validateNonEmptyString(appID);
+
     const data = await this.discloudApp.rest.delete<
       | RESTDeleteApiAppDeleteResult
       | RESTDeleteApiAppAllDeleteResult
@@ -194,6 +205,7 @@ export default class AppManager extends CachedManager<typeof App> {
    * @param options - Options to update your app.
    */
   async profile(appID: string, options: ProfileOptions) {
+    validateNonEmptyString(appID);
     ProfileOptions.parse(options);
 
     const data = await this.discloudApp.rest.put<RESTApiBaseResult>(Routes.appProfile(appID), {
@@ -212,8 +224,10 @@ export default class AppManager extends CachedManager<typeof App> {
    * @param appID - You app id
    */
   async restart(appID: string): Promise<RESTPutApiAppRestartResult>
-  async restart(appID?: "all"): Promise<ApiAppManagerRestartedAll>
-  async restart(appID = "all") {
+  async restart(appID: "all"): Promise<ApiAppManagerRestartedAll>
+  async restart(appID: string) {
+    validateNonEmptyString(appID);
+
     const data = await this.discloudApp.rest.put<
       | RESTPutApiAppRestartResult
       | RESTPutApiAppAllRestartResult
@@ -242,8 +256,10 @@ export default class AppManager extends CachedManager<typeof App> {
    * @param appID - You app id
    */
   async start(appID: string): Promise<RESTPutApiAppStartResult>
-  async start(appID?: "all"): Promise<ApiAppManagerStartedAll>
-  async start(appID = "all") {
+  async start(appID: "all"): Promise<ApiAppManagerStartedAll>
+  async start(appID: string) {
+    validateNonEmptyString(appID);
+
     const data = await this.discloudApp.rest.put<
       | RESTPutApiAppStartResult
       | RESTPutApiAppAllStartResult
@@ -272,8 +288,10 @@ export default class AppManager extends CachedManager<typeof App> {
    * @param appID - You app id
    */
   async stop(appID: string): Promise<RESTPutApiAppStopResult>
-  async stop(appID?: "all"): Promise<ApiAppManagerStopedAll>
-  async stop(appID = "all") {
+  async stop(appID: "all"): Promise<ApiAppManagerStopedAll>
+  async stop(appID: string) {
+    validateNonEmptyString(appID);
+
     const data = await this.discloudApp.rest.put<
       | RESTPutApiAppStopResult
       | RESTPutApiAppAllStopResult
@@ -302,8 +320,10 @@ export default class AppManager extends CachedManager<typeof App> {
    * @param appID - You app id.
    */
   async fetch(appID: string): Promise<App>
-  async fetch(appID?: "all"): Promise<Map<string, App>>
-  async fetch(appID = "all") {
+  async fetch(appID: "all"): Promise<Map<string, App>>
+  async fetch(appID: string) {
+    validateNonEmptyString(appID);
+
     if (appID === "all") return this.#fetchMany();
 
     try {
diff --git a/packages/discloud.app/src/managers/AppTeamManager.ts b/packages/discloud.app/src/managers/AppTeamManager.ts
index 46254bf60..9bef444a1 100644
--- a/packages/discloud.app/src/managers/AppTeamManager.ts
+++ b/packages/discloud.app/src/managers/AppTeamManager.ts
@@ -1,7 +1,7 @@
 import { Routes, type ApiAppTeamManager, type RESTDeleteApiAppTeamResult, type RESTGetApiAppTeamResult, type RESTPostApiAppTeamResult, type RESTPutApiAppTeamResult } from "@discloudapp/api-types/v2";
 import { ModPermissionsBF, type ModPermissionsResolvable } from "@discloudapp/util";
-import z from "zod";
 import type DiscloudApp from "../discloudApp/DiscloudApp";
+import { validateNonEmptyString } from "../util/assertions";
 import BaseManager from "./BaseManager";
 
 /**
@@ -20,8 +20,8 @@ export default class AppTeamManager extends BaseManager {
    * @param perms - The permissions for the mod. See {@link ModPermissionsResolvable}
    */
   async create(appID: string, modID: string, perms: ModPermissionsResolvable): Promise<ApiAppTeamManager> {
-    z.string().parse(appID);
-    z.string().parse(modID);
+    validateNonEmptyString(appID);
+    validateNonEmptyString(modID);
 
     const data = await this.discloudApp.rest.post<RESTPostApiAppTeamResult>(Routes.appTeam(appID), {
       body: {
@@ -41,8 +41,8 @@ export default class AppTeamManager extends BaseManager {
    * @param perms - The permissions for the mod. See {@link ModPermissionsResolvable}
    */
   async edit(appID: string, modID: string, perms: ModPermissionsResolvable): Promise<ApiAppTeamManager> {
-    z.string().parse(appID);
-    z.string().parse(modID);
+    validateNonEmptyString(appID);
+    validateNonEmptyString(modID);
 
     const data = await this.discloudApp.rest.put<RESTPutApiAppTeamResult>(Routes.appTeam(appID), {
       body: {
@@ -62,8 +62,8 @@ export default class AppTeamManager extends BaseManager {
    * @param modID - The mod id
    */
   async delete(appID: string, modID: string): Promise<RESTDeleteApiAppTeamResult> {
-    z.string().parse(appID);
-    z.string().parse(modID);
+    validateNonEmptyString(appID);
+    validateNonEmptyString(modID);
 
     const data = await this.discloudApp.rest.delete<
       RESTDeleteApiAppTeamResult
@@ -76,7 +76,7 @@ export default class AppTeamManager extends BaseManager {
    * Get mods information for your app on Discloud
    */
   async fetch(appID: string) {
-    z.string().parse(appID);
+    validateNonEmptyString(appID);
 
     const data = await this.discloudApp.rest.get<RESTGetApiAppTeamResult>(Routes.appTeam(appID));
 
diff --git a/packages/discloud.app/src/managers/TeamAppManager.ts b/packages/discloud.app/src/managers/TeamAppManager.ts
index e28df5cfd..66b75188e 100644
--- a/packages/discloud.app/src/managers/TeamAppManager.ts
+++ b/packages/discloud.app/src/managers/TeamAppManager.ts
@@ -2,12 +2,12 @@ import { Routes, type ApiAppManagerRestartedAll, type ApiAppManagerStartedAll, t
 import { DiscloudAPIError } from "@discloudapp/rest";
 import { resolveFile } from "@discloudapp/util";
 import { constants } from "http2";
-import z from "zod";
 import type { UpdateAppOptions } from "../@types";
 import type DiscloudApp from "../discloudApp/DiscloudApp";
 import AppBackup from "../structures/AppBackup";
 import TeamApp from "../structures/TeamApp";
 import type TeamAppStatus from "../structures/TeamAppStatus";
+import { validateNumberType, validateNonEmptyString } from "../util/assertions";
 import CachedManager from "./CachedManager";
 
 /**
@@ -25,6 +25,8 @@ export default class TeamAppManager extends CachedManager<typeof TeamApp> {
    */
   async status(appID: string): Promise<TeamAppStatus>
   async status(appID: string) {
+    validateNonEmptyString(appID);
+
     const data = await this.discloudApp.rest.get<RESTGetApiAppStatusResult>(Routes.teamStatus(appID));
 
     return this._add(data.apps).status;
@@ -36,8 +38,10 @@ export default class TeamAppManager extends CachedManager<typeof TeamApp> {
    * @param appID - Your team app id
    */
   async terminal(appID: string): Promise<ApiTerminal>
-  async terminal(appID?: "all"): Promise<Map<string, ApiTerminal>>
-  async terminal(appID = "all") {
+  async terminal(appID: "all"): Promise<Map<string, ApiTerminal>>
+  async terminal(appID: string) {
+    validateNonEmptyString(appID);
+
     const data = await this.discloudApp.rest.get<
       | RESTGetApiAppLogResult
       | RESTGetApiAppAllLogResult
@@ -61,8 +65,10 @@ export default class TeamAppManager extends CachedManager<typeof TeamApp> {
    * @param appID - Your team app id
    */
   async backup(appID: string): Promise<AppBackup>
-  async backup(appID?: "all"): Promise<Map<string, AppBackup>>
-  async backup(appID = "all") {
+  async backup(appID: "all"): Promise<Map<string, AppBackup>>
+  async backup(appID: string) {
+    validateNonEmptyString(appID);
+
     const data = await this.discloudApp.rest.get<
       | RESTGetApiAppBackupResult
       | RESTGetApiAppAllBackupResult
@@ -88,8 +94,8 @@ export default class TeamAppManager extends CachedManager<typeof TeamApp> {
    * @param quantity - Minimum values is `100` to `bot` or `512` for `site`
    */
   async ram(appID: string, quantity: number) {
-    z.string().parse(appID);
-    z.number().parse(quantity);
+    validateNonEmptyString(appID);
+    validateNumberType(quantity);
 
     const data = await this.discloudApp.rest.put<RESTPutApiAppRamResult>(Routes.teamRam(appID), {
       body: {
@@ -113,7 +119,7 @@ export default class TeamAppManager extends CachedManager<typeof TeamApp> {
    * @param options - Options to update your app.
    */
   async update(appID: string, options: UpdateAppOptions) {
-    z.string().parse(appID);
+    validateNonEmptyString(appID);
 
     options.file = await resolveFile(options.file);
 
@@ -132,8 +138,10 @@ export default class TeamAppManager extends CachedManager<typeof TeamApp> {
    * @param appID - Your team app id
    */
   async restart(appID: string): Promise<RESTPutApiAppRestartResult>
-  async restart(appID?: "all"): Promise<ApiAppManagerRestartedAll>
-  async restart(appID = "all") {
+  async restart(appID: "all"): Promise<ApiAppManagerRestartedAll>
+  async restart(appID: string) {
+    validateNonEmptyString(appID);
+
     const data = await this.discloudApp.rest.put<
       | RESTPutApiAppRestartResult
       | RESTPutApiAppAllRestartResult
@@ -162,8 +170,10 @@ export default class TeamAppManager extends CachedManager<typeof TeamApp> {
    * @param appID - Your team app id
    */
   async start(appID: string): Promise<RESTPutApiAppStartResult>
-  async start(appID?: "all"): Promise<ApiAppManagerStartedAll>
-  async start(appID = "all") {
+  async start(appID: "all"): Promise<ApiAppManagerStartedAll>
+  async start(appID: string) {
+    validateNonEmptyString(appID);
+
     const data = await this.discloudApp.rest.put<
       | RESTPutApiAppStartResult
       | RESTPutApiAppAllStartResult
@@ -192,8 +202,10 @@ export default class TeamAppManager extends CachedManager<typeof TeamApp> {
    * @param appID - Your team app id
    */
   async stop(appID: string): Promise<RESTPutApiAppStopResult>
-  async stop(appID?: "all"): Promise<ApiAppManagerStopedAll>
-  async stop(appID = "all") {
+  async stop(appID: "all"): Promise<ApiAppManagerStopedAll>
+  async stop(appID: string) {
+    validateNonEmptyString(appID);
+
     const data = await this.discloudApp.rest.put<
       | RESTPutApiAppStopResult
       | RESTPutApiAppAllStopResult
diff --git a/packages/discloud.app/src/util/assertions.ts b/packages/discloud.app/src/util/assertions.ts
new file mode 100644
index 000000000..225ae136b
--- /dev/null
+++ b/packages/discloud.app/src/util/assertions.ts
@@ -0,0 +1,20 @@
+import assert from "assert";
+
+export function validateStringType(value: string): void
+export function validateStringType(value: unknown): void
+export function validateStringType(value: unknown) {
+  assert(typeof value === "string", new TypeError(`Expected string but received ${typeof value}`));
+}
+
+export function validateNonEmptyString(value: string): void
+export function validateNonEmptyString(value: unknown): void
+export function validateNonEmptyString(value: any) {
+  validateStringType(value);
+  assert(value.length, new RangeError("The string cannot be empty"));
+}
+
+export function validateNumberType(value: number): void
+export function validateNumberType(value: unknown): void
+export function validateNumberType(value: unknown) {
+  assert(typeof value === "number", new TypeError(`Expected number but received ${typeof value}`));
+}