diff --git a/src/schemas/tutor.schema.ts b/src/schemas/tutor.schema.ts
new file mode 100644
index 0000000..7ead1c9
--- /dev/null
+++ b/src/schemas/tutor.schema.ts
@@ -0,0 +1,99 @@
+import { firestore } from "@/config";
+import { z } from "zod";
+
+export const tutorSchema = z.object({
+  id: z.string(),
+  name: z.string().min(3, "Name must be at least 3 characters"),
+  phoneNum: z
+    .string()
+    .min(10, "Phone number must be at least 10 characters")
+    .optional(),
+  location: z
+    .object({
+      latitude: z.number({ message: "Latitude must be a number" }),
+      longitude: z.number({ message: "Longitude must be a number" }),
+    })
+    .optional(),
+  services: z
+    .array(z.string())
+    .superRefine(async (services, ctx) => {
+      // Validate that the services are valid by checking the tutor_services collection
+      try {
+        const servicesSnapshot = await firestore
+          .collection("tutor_services")
+          .get();
+        const validServices = servicesSnapshot.docs.map((doc) => doc.id);
+        const invalidServices = services.filter(
+          (service) => !validServices.includes(service),
+        );
+
+        if (invalidServices.length > 0) {
+          ctx.addIssue({
+            code: z.ZodIssueCode.custom,
+            message: `Invalid services found: ${invalidServices.join(", ")}`,
+          });
+        }
+      } catch (error) {
+        ctx.addIssue({
+          code: z.ZodIssueCode.custom,
+          message: "Failed to validate services due to an internal error",
+        });
+      }
+    })
+    .optional(),
+  coverageRange: z.number().optional(),
+  createdAt: z.date(),
+  updatedAt: z.date().optional(),
+  lastSeen: z.date().optional(),
+});
+
+export const tutorServiceSchema = z.object({
+  id: z.string(),
+  tutorId: z.string().superRefine(async (tutorId, ctx) => {
+    // Validate that the tutor exists by checking the tutors collection
+    try {
+      const tutorSnapshot = await firestore
+        .collection("tutors")
+        .doc(tutorId)
+        .get();
+      if (!tutorSnapshot.exists) {
+        ctx.addIssue({
+          code: z.ZodIssueCode.custom,
+          message: "Tutor does not exist",
+        });
+      }
+    } catch (error) {
+      ctx.addIssue({
+        code: z.ZodIssueCode.custom,
+        message: "Failed to validate tutor due to an internal error",
+      });
+    }
+  }),
+  subjectId: z.string().superRefine(async (subjectId, ctx) => {
+    // Validate that the subject exists by checking the subjects collection
+    try {
+      const subjectSnapshot = await firestore
+        .collection("subjects")
+        .doc(subjectId)
+        .get();
+      if (!subjectSnapshot.exists) {
+        ctx.addIssue({
+          code: z.ZodIssueCode.custom,
+          message: "Subject does not exist",
+        });
+      }
+    } catch (error) {
+      ctx.addIssue({
+        code: z.ZodIssueCode.custom,
+        message: "Failed to validate subject due to an internal error",
+      });
+    }
+  }),
+  // About the tutor's experience with the subject
+  aboutYou: z.string().optional(),
+  // Tutor's teaching methodology
+  teachingMethodology: z.string().optional(),
+  hourlyRate: z.number().optional(),
+  createdAt: z.date(),
+  updatedAt: z.date().optional(),
+});
diff --git a/src/schemas/user.schema.ts b/src/schemas/user.schema.ts
index 597d5d4..9b7dc5f 100644
--- a/src/schemas/user.schema.ts
+++ b/src/schemas/user.schema.ts
@@ -15,7 +15,7 @@ export const userSchema = z.object({
     })
     .optional(),
   createdAt: z.date(),
-  updatedAt: z.date(),
+  updatedAt: z.date().optional(),
   lastSeen: z.date().optional(),
   interests: z
     .array(z.string())
diff --git a/src/types.ts b/src/types.ts
index dda0413..70b1772 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -1,3 +1,4 @@
+import { tutorSchema, tutorServiceSchema } from "@schemas/tutor.schema";
 import { userSchema } from "@schemas/user.schema";
 import type { RequestHandler } from "express";
 import { z } from "zod";
@@ -12,16 +13,8 @@ export interface Controller<T extends RequestData = RequestData>
   extends RequestHandler<T["params"], {}, T["body"], T["query"]> {}
 
 export type User = z.infer<typeof userSchema>;
-
-export interface Tutor {
-  id: string;
-  phoneNum?: string;
-  location?: unknown; // not sure now
-  coverageRange: number;
-  createdAt: Date;
-  updatedAt: Date;
-  lastSeen?: Date;
-}
+export type Tutor = z.infer<typeof tutorSchema>;
+export type Service = z.infer<typeof tutorServiceSchema>;
 
 export interface Subject {
   name: string;