diff --git a/api/routes/_.context.ts b/api/routes/_.context.ts
index 2bbd799..7713817 100644
--- a/api/routes/_.context.ts
+++ b/api/routes/_.context.ts
@@ -13,87 +13,364 @@ import type { Pet } from "../types/components/schemas/Pet.js";
 import type { User } from "../types/components/schemas/User.js";
 import type { Order } from "../types/components/schemas/Order.js";
 
+interface Scenario {
+  pets: Pet[];
+  users: User[];
+  orders: Order[];
+}
+
+/**
+ * Pre-defined scenarios that can be loaded into the context at any time.
+ *
+ * Load a scenario from the REPL with:
+ *   context.loadScenario("empty")
+ *
+ * Available scenarios: startup, empty, sold-out, busy
+ */
+const SCENARIOS: Record<string, Scenario> = {
+  /**
+   * Default startup state: a small mix of pets, a couple of users, and a
+   * couple of orders — enough for basic end-to-end exploration.
+   */
+  startup: {
+    pets: [
+      {
+        id: 1,
+        name: "Buddy",
+        category: { id: 1, name: "Dogs" },
+        photoUrls: ["https://example.com/buddy.jpg"],
+        tags: [{ id: 1, name: "friendly" }],
+        status: "available",
+      },
+      {
+        id: 2,
+        name: "Whiskers",
+        category: { id: 2, name: "Cats" },
+        photoUrls: ["https://example.com/whiskers.jpg"],
+        tags: [{ id: 2, name: "indoor" }],
+        status: "available",
+      },
+      {
+        id: 3,
+        name: "Goldie",
+        category: { id: 3, name: "Fish" },
+        photoUrls: ["https://example.com/goldie.jpg"],
+        tags: [],
+        status: "pending",
+      },
+      {
+        id: 4,
+        name: "Max",
+        category: { id: 1, name: "Dogs" },
+        photoUrls: ["https://example.com/max.jpg"],
+        tags: [{ id: 3, name: "trained" }],
+        status: "sold",
+      },
+    ],
+    users: [
+      {
+        id: 1,
+        username: "user1",
+        firstName: "John",
+        lastName: "Doe",
+        email: "john@example.com",
+        password: "password123",
+        phone: "555-1234",
+        userStatus: 1,
+      },
+      {
+        id: 2,
+        username: "jane_smith",
+        firstName: "Jane",
+        lastName: "Smith",
+        email: "jane@example.com",
+        password: "secret456",
+        phone: "555-5678",
+        userStatus: 1,
+      },
+    ],
+    orders: [
+      {
+        id: 1,
+        petId: 1,
+        quantity: 1,
+        shipDate: "2024-01-15T10:00:00Z",
+        status: "placed",
+        complete: false,
+      },
+      {
+        id: 2,
+        petId: 4,
+        quantity: 1,
+        shipDate: "2024-01-10T08:00:00Z",
+        status: "delivered",
+        complete: true,
+      },
+    ],
+  },
+
+  /**
+   * Empty store: no pets, users, or orders.
+   * Useful for testing the "no data" state or building up state from scratch.
+   */
+  empty: {
+    pets: [],
+    users: [],
+    orders: [],
+  },
+
+  /**
+   * Sold-out store: all pets have been sold and all orders are complete.
+   * Useful for testing behaviour when no pets are available.
+   */
+  "sold-out": {
+    pets: [
+      {
+        id: 1,
+        name: "Buddy",
+        category: { id: 1, name: "Dogs" },
+        photoUrls: ["https://example.com/buddy.jpg"],
+        tags: [{ id: 1, name: "friendly" }],
+        status: "sold",
+      },
+      {
+        id: 2,
+        name: "Whiskers",
+        category: { id: 2, name: "Cats" },
+        photoUrls: ["https://example.com/whiskers.jpg"],
+        tags: [{ id: 2, name: "indoor" }],
+        status: "sold",
+      },
+      {
+        id: 3,
+        name: "Goldie",
+        category: { id: 3, name: "Fish" },
+        photoUrls: ["https://example.com/goldie.jpg"],
+        tags: [],
+        status: "sold",
+      },
+    ],
+    users: [
+      {
+        id: 1,
+        username: "user1",
+        firstName: "John",
+        lastName: "Doe",
+        email: "john@example.com",
+        password: "password123",
+        phone: "555-1234",
+        userStatus: 1,
+      },
+    ],
+    orders: [
+      {
+        id: 1,
+        petId: 1,
+        quantity: 1,
+        shipDate: "2024-01-10T08:00:00Z",
+        status: "delivered",
+        complete: true,
+      },
+      {
+        id: 2,
+        petId: 2,
+        quantity: 1,
+        shipDate: "2024-01-11T09:00:00Z",
+        status: "delivered",
+        complete: true,
+      },
+      {
+        id: 3,
+        petId: 3,
+        quantity: 1,
+        shipDate: "2024-01-12T10:00:00Z",
+        status: "delivered",
+        complete: true,
+      },
+    ],
+  },
+
+  /**
+   * Busy store: a large and varied inventory with many pending orders.
+   * Useful for load-testing UI components or pagination.
+   */
+  busy: {
+    pets: [
+      {
+        id: 1,
+        name: "Buddy",
+        category: { id: 1, name: "Dogs" },
+        photoUrls: ["https://example.com/buddy.jpg"],
+        tags: [{ id: 1, name: "friendly" }],
+        status: "available",
+      },
+      {
+        id: 2,
+        name: "Whiskers",
+        category: { id: 2, name: "Cats" },
+        photoUrls: ["https://example.com/whiskers.jpg"],
+        tags: [{ id: 2, name: "indoor" }],
+        status: "available",
+      },
+      {
+        id: 3,
+        name: "Goldie",
+        category: { id: 3, name: "Fish" },
+        photoUrls: ["https://example.com/goldie.jpg"],
+        tags: [],
+        status: "available",
+      },
+      {
+        id: 4,
+        name: "Max",
+        category: { id: 1, name: "Dogs" },
+        photoUrls: ["https://example.com/max.jpg"],
+        tags: [{ id: 3, name: "trained" }],
+        status: "available",
+      },
+      {
+        id: 5,
+        name: "Tweety",
+        category: { id: 4, name: "Birds" },
+        photoUrls: ["https://example.com/tweety.jpg"],
+        tags: [{ id: 4, name: "singing" }],
+        status: "available",
+      },
+      {
+        id: 6,
+        name: "Bella",
+        category: { id: 1, name: "Dogs" },
+        photoUrls: ["https://example.com/bella.jpg"],
+        tags: [{ id: 1, name: "friendly" }],
+        status: "pending",
+      },
+      {
+        id: 7,
+        name: "Luna",
+        category: { id: 2, name: "Cats" },
+        photoUrls: ["https://example.com/luna.jpg"],
+        tags: [{ id: 2, name: "indoor" }],
+        status: "pending",
+      },
+      {
+        id: 8,
+        name: "Charlie",
+        category: { id: 1, name: "Dogs" },
+        photoUrls: ["https://example.com/charlie.jpg"],
+        tags: [{ id: 3, name: "trained" }],
+        status: "sold",
+      },
+    ],
+    users: [
+      {
+        id: 1,
+        username: "user1",
+        firstName: "John",
+        lastName: "Doe",
+        email: "john@example.com",
+        password: "password123",
+        phone: "555-1234",
+        userStatus: 1,
+      },
+      {
+        id: 2,
+        username: "jane_smith",
+        firstName: "Jane",
+        lastName: "Smith",
+        email: "jane@example.com",
+        password: "secret456",
+        phone: "555-5678",
+        userStatus: 1,
+      },
+      {
+        id: 3,
+        username: "bob_jones",
+        firstName: "Bob",
+        lastName: "Jones",
+        email: "bob@example.com",
+        password: "pass789",
+        phone: "555-9012",
+        userStatus: 1,
+      },
+    ],
+    orders: [
+      {
+        id: 1,
+        petId: 6,
+        quantity: 1,
+        shipDate: "2024-01-15T10:00:00Z",
+        status: "placed",
+        complete: false,
+      },
+      {
+        id: 2,
+        petId: 7,
+        quantity: 1,
+        shipDate: "2024-01-16T11:00:00Z",
+        status: "approved",
+        complete: false,
+      },
+      {
+        id: 3,
+        petId: 8,
+        quantity: 1,
+        shipDate: "2024-01-10T08:00:00Z",
+        status: "delivered",
+        complete: true,
+      },
+      {
+        id: 4,
+        petId: 1,
+        quantity: 2,
+        shipDate: "2024-01-17T09:00:00Z",
+        status: "placed",
+        complete: false,
+      },
+    ],
+  },
+};
+
 export class Context {
-  pets: Pet[] = [
-    {
-      id: 1,
-      name: "Buddy",
-      category: { id: 1, name: "Dogs" },
-      photoUrls: ["https://example.com/buddy.jpg"],
-      tags: [{ id: 1, name: "friendly" }],
-      status: "available",
-    },
-    {
-      id: 2,
-      name: "Whiskers",
-      category: { id: 2, name: "Cats" },
-      photoUrls: ["https://example.com/whiskers.jpg"],
-      tags: [{ id: 2, name: "indoor" }],
-      status: "available",
-    },
-    {
-      id: 3,
-      name: "Goldie",
-      category: { id: 3, name: "Fish" },
-      photoUrls: ["https://example.com/goldie.jpg"],
-      tags: [],
-      status: "pending",
-    },
-    {
-      id: 4,
-      name: "Max",
-      category: { id: 1, name: "Dogs" },
-      photoUrls: ["https://example.com/max.jpg"],
-      tags: [{ id: 3, name: "trained" }],
-      status: "sold",
-    },
-  ];
-
-  users: User[] = [
-    {
-      id: 1,
-      username: "user1",
-      firstName: "John",
-      lastName: "Doe",
-      email: "john@example.com",
-      password: "password123",
-      phone: "555-1234",
-      userStatus: 1,
-    },
-    {
-      id: 2,
-      username: "jane_smith",
-      firstName: "Jane",
-      lastName: "Smith",
-      email: "jane@example.com",
-      password: "secret456",
-      phone: "555-5678",
-      userStatus: 1,
-    },
-  ];
-
-  orders: Order[] = [
-    {
-      id: 1,
-      petId: 1,
-      quantity: 1,
-      shipDate: "2024-01-15T10:00:00Z",
-      status: "placed",
-      complete: false,
-    },
-    {
-      id: 2,
-      petId: 4,
-      quantity: 1,
-      shipDate: "2024-01-10T08:00:00Z",
-      status: "delivered",
-      complete: true,
-    },
-  ];
-
-  private nextPetId = 5;
-  private nextUserId = 3;
-  private nextOrderId = 3;
+  pets: Pet[] = [];
+  users: User[] = [];
+  orders: Order[] = [];
+
+  private nextPetId = 1;
+  private nextUserId = 1;
+  private nextOrderId = 1;
+
+  constructor() {
+    this.loadScenario("startup");
+  }
+
+  /**
+   * Load a named scenario, replacing all current pets, users, and orders.
+   *
+   * Available scenarios: startup, empty, sold-out, busy
+   *
+   * Example (from the REPL):
+   *   context.loadScenario("empty")
+   */
+  loadScenario(name: string): void {
+    const scenario = SCENARIOS[name];
+    if (!scenario) {
+      throw new Error(
+        `Scenario "${name}" not found. Available: ${Object.keys(SCENARIOS).join(", ")}`,
+      );
+    }
+    this.pets = scenario.pets.map((p) => ({ ...p }));
+    this.users = scenario.users.map((u) => ({ ...u }));
+    this.orders = scenario.orders.map((o) => ({ ...o }));
+    this.nextPetId = Math.max(0, ...this.pets.map((p) => p.id ?? 0)) + 1;
+    this.nextUserId = Math.max(0, ...this.users.map((u) => u.id ?? 0)) + 1;
+    this.nextOrderId =
+      Math.max(0, ...this.orders.map((o) => o.id ?? 0)) + 1;
+  }
+
+  /** Returns the names of all available scenarios. */
+  get scenarios(): string[] {
+    return Object.keys(SCENARIOS);
+  }
 
   addPet(pet: Pet): Pet {
     const newPet = { ...pet, id: this.nextPetId++ };
diff --git a/test/context.test.ts b/test/context.test.ts
index 4fd0177..eabd582 100644
--- a/test/context.test.ts
+++ b/test/context.test.ts
@@ -252,4 +252,107 @@ describe("Context", () => {
       assert.equal(inventory.available, 1);
     });
   });
+
+  describe("scenarios", () => {
+    it("lists available scenario names", () => {
+      assert.ok(context.scenarios.includes("startup"));
+      assert.ok(context.scenarios.includes("empty"));
+      assert.ok(context.scenarios.includes("sold-out"));
+      assert.ok(context.scenarios.includes("busy"));
+    });
+  });
+
+  describe("loadScenario", () => {
+    it("loads the startup scenario with four pets", () => {
+      context.loadScenario("startup");
+      assert.equal(context.pets.length, 4);
+    });
+
+    it("loads the startup scenario with two users", () => {
+      context.loadScenario("startup");
+      assert.equal(context.users.length, 2);
+    });
+
+    it("loads the startup scenario with two orders", () => {
+      context.loadScenario("startup");
+      assert.equal(context.orders.length, 2);
+    });
+
+    it("loads the empty scenario with no pets", () => {
+      context.loadScenario("empty");
+      assert.equal(context.pets.length, 0);
+    });
+
+    it("loads the empty scenario with no users", () => {
+      context.loadScenario("empty");
+      assert.equal(context.users.length, 0);
+    });
+
+    it("loads the empty scenario with no orders", () => {
+      context.loadScenario("empty");
+      assert.equal(context.orders.length, 0);
+    });
+
+    it("assigns a new id after loading the empty scenario", () => {
+      context.loadScenario("empty");
+      const pet = context.addPet({ name: "Rex", photoUrls: [] });
+      assert.ok(typeof pet.id === "number");
+    });
+
+    it("loads the sold-out scenario where all pets are sold", () => {
+      context.loadScenario("sold-out");
+      assert.ok(context.pets.every((p) => p.status === "sold"));
+    });
+
+    it("loads the sold-out scenario where all orders are complete", () => {
+      context.loadScenario("sold-out");
+      assert.ok(context.orders.every((o) => o.complete === true));
+    });
+
+    it("loads the busy scenario with more than four pets", () => {
+      context.loadScenario("busy");
+      assert.ok(context.pets.length > 4);
+    });
+
+    it("loads the busy scenario with more than two users", () => {
+      context.loadScenario("busy");
+      assert.ok(context.users.length > 2);
+    });
+
+    it("loads the busy scenario with more than two orders", () => {
+      context.loadScenario("busy");
+      assert.ok(context.orders.length > 2);
+    });
+
+    it("replaces existing data when switching scenarios", () => {
+      context.addPet({ name: "Extra", photoUrls: [] });
+      context.loadScenario("empty");
+      assert.equal(context.pets.length, 0);
+    });
+
+    it("does not share pet array references between loads", () => {
+      context.loadScenario("startup");
+      context.pets.push({ name: "Extra", photoUrls: [] });
+      context.loadScenario("startup");
+      assert.equal(context.pets.length, 4);
+    });
+
+    it("throws an error for an unknown scenario name", () => {
+      assert.throws(() => context.loadScenario("nonexistent"), /nonexistent/);
+    });
+
+    it("error message lists available scenarios", () => {
+      assert.throws(
+        () => context.loadScenario("nonexistent"),
+        /startup.*empty|empty.*startup/,
+      );
+    });
+
+    it("assigns sequential ids after loading a non-empty scenario", () => {
+      context.loadScenario("startup");
+      const first = context.addPet({ name: "A", photoUrls: [] });
+      const second = context.addPet({ name: "B", photoUrls: [] });
+      assert.equal((second.id as number) - (first.id as number), 1);
+    });
+  });
 });