diff --git a/libraries/validation-tools/handleValidationError.js b/libraries/validation-tools/handleValidationError.js
deleted file mode 100644
index 8f789a83c7..0000000000
--- a/libraries/validation-tools/handleValidationError.js
+++ /dev/null
@@ -1,17 +0,0 @@
-const { isZodErrorLike, fromError } = require('zod-validation-error')
-/**
- * @typedef {import('express').ErrorRequestHandler} ErrorRequestHandler
- */
-
-const handleValidationError = [
-  /** @type {ErrorRequestHandler} */
-  (err, req, res, next) => {
-    if (!isZodErrorLike(err)) {
-      return next(err)
-    }
-
-    res.status(400).json({ ...fromError(err), statusCode: 400 })
-  },
-]
-
-module.exports = { handleValidationError }
diff --git a/libraries/validation-tools/index.js b/libraries/validation-tools/index.js
index bce67b5e41..0536e62b27 100644
--- a/libraries/validation-tools/index.js
+++ b/libraries/validation-tools/index.js
@@ -2,12 +2,10 @@ const { ParamsError } = require('./Errors')
 const { z } = require('zod')
 const { zz } = require('./zodHelpers')
 const { validateReq } = require('./validateReq')
-const { handleValidationError } = require('./handleValidationError')
 
 module.exports = {
   z,
   zz,
   validateReq,
-  handleValidationError,
   ParamsError,
 }
diff --git a/libraries/validation-tools/package.json b/libraries/validation-tools/package.json
index 9439e7cf56..3aa85ff7bb 100644
--- a/libraries/validation-tools/package.json
+++ b/libraries/validation-tools/package.json
@@ -22,8 +22,7 @@
   "dependencies": {
     "@overleaf/o-error": "*",
     "mongodb": "^6.12.0",
-    "zod": "^4.1.8",
-    "zod-validation-error": "^4.0.1"
+    "zod": "^4.1.8"
   },
   "devDependencies": {
     "typescript": "^5.0.4",
diff --git a/package-lock.json b/package-lock.json
index 47f3623e97..3846600a01 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -541,8 +541,7 @@
       "dependencies": {
         "@overleaf/o-error": "*",
         "mongodb": "^6.12.0",
-        "zod": "^4.1.8",
-        "zod-validation-error": "^4.0.1"
+        "zod": "^4.1.8"
       },
       "devDependencies": {
         "typescript": "^5.0.4",
@@ -51425,9 +51424,9 @@
         "@overleaf/promise-utils": "*",
         "@overleaf/settings": "*",
         "@overleaf/stream-utils": "*",
-        "@overleaf/validation-tools": "*",
         "body-parser": "^1.20.3",
         "bunyan": "^1.8.15",
+        "celebrate": "^15.0.3",
         "express": "^4.21.2",
         "p-limit": "^3.1.0"
       },
diff --git a/services/web/app/src/infrastructure/Server.mjs b/services/web/app/src/infrastructure/Server.mjs
index f3cda6b84c..4e13a8e143 100644
--- a/services/web/app/src/infrastructure/Server.mjs
+++ b/services/web/app/src/infrastructure/Server.mjs
@@ -2,6 +2,7 @@ import express from 'express'
 import Settings from '@overleaf/settings'
 import logger from '@overleaf/logger'
 import metrics from '@overleaf/metrics'
+import Validation from './Validation.js'
 import csp, { removeCSPHeaders } from './CSP.mjs'
 import Router from '../router.mjs'
 import helmet from 'helmet'
@@ -37,7 +38,6 @@ import os from 'node:os'
 import http from 'node:http'
 import { fileURLToPath } from 'node:url'
 import serveStaticWrapper from './ServeStaticWrapper.mjs'
-import { handleValidationError } from '@overleaf/validation-tools'
 
 const { hasAdminAccess } = AdminAuthorizationHelper
 const sessionsRedisClient = UserSessionsRedis.client()
@@ -356,17 +356,17 @@ const server = http.createServer(app)
 if (Settings.enabledServices.includes('api')) {
   logger.debug({}, 'providing api router')
   app.use(privateApiRouter)
-  app.use(handleValidationError)
+  app.use(Validation.errorMiddleware)
   app.use(ErrorController.handleApiError)
 }
 
 if (Settings.enabledServices.includes('web')) {
   logger.debug({}, 'providing web router')
   app.use(publicApiRouter) // public API goes with web router for public access
-  app.use(handleValidationError)
+  app.use(Validation.errorMiddleware)
   app.use(ErrorController.handleApiError)
   app.use(webRouter)
-  app.use(handleValidationError)
+  app.use(Validation.errorMiddleware)
   app.use(ErrorController.handleError)
 }
 
diff --git a/services/web/app/src/infrastructure/Validation.js b/services/web/app/src/infrastructure/Validation.js
index 209f56a848..8e8c9e572b 100644
--- a/services/web/app/src/infrastructure/Validation.js
+++ b/services/web/app/src/infrastructure/Validation.js
@@ -7,6 +7,22 @@ const {
   zz,
   ParamsError,
 } = require('@overleaf/validation-tools')
+const { isZodErrorLike, fromError } = require('zod-validation-error')
+
+/**
+ * @typedef {import('express').ErrorRequestHandler} ErrorRequestHandler
+ */
+
+const errorMiddleware = [
+  /** @type {ErrorRequestHandler} */
+  (err, req, res, next) => {
+    if (!isZodErrorLike(err)) {
+      return next(err)
+    }
+
+    res.status(400).json({ ...fromError(err), statusCode: 400 })
+  },
+]
 
 const validateReqWeb = (req, schema) => {
   try {
@@ -21,6 +37,7 @@ const validateReqWeb = (req, schema) => {
 }
 
 module.exports = {
+  errorMiddleware,
   validateReq: validateReqWeb,
   z,
   zz,