diff --git a/packages/core/src/entities/models/article.ts b/packages/core/src/entities/models/article.ts
new file mode 100644
index 0000000..59e15bd
--- /dev/null
+++ b/packages/core/src/entities/models/article.ts
@@ -0,0 +1,17 @@
+import { z } from "zod";
+
+export const articleStatusSchema = z.enum(["draft", "published"]);
+
+export const articleSchema = z.object({
+  id: z.string(),
+  title: z.string().min(1).max(255),
+  slug: z.string().min(1).max(255),
+  content: z.string(),
+  status: articleStatusSchema.default("draft"),
+  authorId: z.string(),
+  createdAt: z.date(),
+  updatedAt: z.date(),
+});
+
+export type Article = z.infer<typeof articleSchema>;
+export type ArticleStatus = z.infer<typeof articleStatusSchema>;
diff --git a/packages/core/src/entities/models/cookie.ts b/packages/core/src/entities/models/cookie.ts
new file mode 100644
index 0000000..f3dfa4a
--- /dev/null
+++ b/packages/core/src/entities/models/cookie.ts
@@ -0,0 +1,15 @@
+type CookieAttributes = {
+  secure?: boolean;
+  path?: string;
+  domain?: string;
+  sameSite?: "lax" | "strict" | "none";
+  httpOnly?: boolean;
+  maxAge?: number;
+  expires?: Date;
+};
+
+export type Cookie = {
+  name: string;
+  value: string;
+  attributes: CookieAttributes;
+};
diff --git a/packages/core/src/entities/models/index.ts b/packages/core/src/entities/models/index.ts
new file mode 100644
index 0000000..b852b8b
--- /dev/null
+++ b/packages/core/src/entities/models/index.ts
@@ -0,0 +1,9 @@
+export { userSchema, type User } from "./user.js";
+export {
+  articleSchema,
+  articleStatusSchema,
+  type Article,
+  type ArticleStatus,
+} from "./article.js";
+export { sessionSchema, type Session } from "./session.js";
+export type { Cookie } from "./cookie.js";
diff --git a/packages/core/src/entities/models/session.ts b/packages/core/src/entities/models/session.ts
new file mode 100644
index 0000000..cedf8a9
--- /dev/null
+++ b/packages/core/src/entities/models/session.ts
@@ -0,0 +1,9 @@
+import { z } from "zod";
+
+export const sessionSchema = z.object({
+  id: z.string(),
+  userId: z.string(),
+  expiresAt: z.date(),
+});
+
+export type Session = z.infer<typeof sessionSchema>;
diff --git a/packages/core/src/entities/models/user.ts b/packages/core/src/entities/models/user.ts
new file mode 100644
index 0000000..3de2240
--- /dev/null
+++ b/packages/core/src/entities/models/user.ts
@@ -0,0 +1,9 @@
+import { z } from "zod";
+
+export const userSchema = z.object({
+  id: z.string(),
+  username: z.string().min(3).max(31),
+  passwordHash: z.string().min(6).max(255),
+});
+
+export type User = z.infer<typeof userSchema>;