diff --git a/package-lock.json b/package-lock.json
index 1cfa178..a99f958 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -636,6 +636,7 @@
       "resolved": "https://registry.npmjs.org/@opentelemetry/api/-/api-1.9.0.tgz",
       "integrity": "sha512-3giAOQvZiH5F9bMlMiv8+GSPMeqg0dbaeo58/0SlA9sxSqZhnUtxzX9/2FzyhS9sWQf5S0GJE0AKBrFqjpeYcg==",
       "license": "Apache-2.0",
+      "peer": true,
       "engines": {
         "node": ">=8.0.0"
       }
@@ -657,6 +658,7 @@
       "resolved": "https://registry.npmjs.org/@opentelemetry/context-async-hooks/-/context-async-hooks-2.5.1.tgz",
       "integrity": "sha512-MHbu8XxCHcBn6RwvCt2Vpn1WnLMNECfNKYB14LI5XypcgH4IE0/DiVifVR9tAkwPMyLXN8dOoPJfya3IryLQVw==",
       "license": "Apache-2.0",
+      "peer": true,
       "engines": {
         "node": "^18.19.0 || >=20.6.0"
       },
@@ -669,6 +671,7 @@
       "resolved": "https://registry.npmjs.org/@opentelemetry/core/-/core-2.5.1.tgz",
       "integrity": "sha512-Dwlc+3HAZqpgTYq0MUyZABjFkcrKTePwuiFVLjahGD8cx3enqihmpAmdgNFO1R4m/sIe5afjJrA25Prqy4NXlA==",
       "license": "Apache-2.0",
+      "peer": true,
       "dependencies": {
         "@opentelemetry/semantic-conventions": "^1.29.0"
       },
@@ -1092,6 +1095,7 @@
       "resolved": "https://registry.npmjs.org/@opentelemetry/resources/-/resources-2.5.1.tgz",
       "integrity": "sha512-BViBCdE/GuXRlp9k7nS1w6wJvY5fnFX5XvuEtWsTAOQFIO89Eru7lGW3WbfbxtCuZ/GbrJfAziXG0w0dpxL7eQ==",
       "license": "Apache-2.0",
+      "peer": true,
       "dependencies": {
         "@opentelemetry/core": "2.5.1",
         "@opentelemetry/semantic-conventions": "^1.29.0"
@@ -1108,6 +1112,7 @@
       "resolved": "https://registry.npmjs.org/@opentelemetry/sdk-trace-base/-/sdk-trace-base-2.5.1.tgz",
       "integrity": "sha512-iZH3Gw8cxQn0gjpOjJMmKLd9GIaNh/E3v3ST67vyzLSxHBs14HsG4dy7jMYyC5WXGdBVEcM7U/XTF5hCQxjDMw==",
       "license": "Apache-2.0",
+      "peer": true,
       "dependencies": {
         "@opentelemetry/core": "2.5.1",
         "@opentelemetry/resources": "2.5.1",
@@ -1125,6 +1130,7 @@
       "resolved": "https://registry.npmjs.org/@opentelemetry/semantic-conventions/-/semantic-conventions-1.39.0.tgz",
       "integrity": "sha512-R5R9tb2AXs2IRLNKLBJDynhkfmx7mX0vi8NkhZb3gUkPWHn6HXk5J8iQ/dql0U3ApfWym4kXXmBDRGO+oeOfjg==",
       "license": "Apache-2.0",
+      "peer": true,
       "engines": {
         "node": ">=14"
       }
@@ -1506,6 +1512,7 @@
       "integrity": "sha512-LEyamqS7W5HB3ujJyvi0HQK/dtVINZvd5mAAp9eT5S/ujByGjiZLCzPcHVzuXbpJDJF/cxwHlfceVUDZ2lnSTw==",
       "dev": true,
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "@eslint-community/eslint-utils": "^4.8.0",
         "@eslint-community/regexpp": "^4.12.1",
@@ -1626,6 +1633,7 @@
       "integrity": "sha512-vPZZsiOKaBAIATpFE2uMI4w5IRwdv/FpQ+qZZMR4E+PeOcM4OeoEbqxRMnywdxP19TyB/3h6QBB0EWon7letSQ==",
       "dev": true,
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "@typescript-eslint/types": "^8.35.0",
         "comment-parser": "^1.4.1",
@@ -2274,6 +2282,7 @@
       "resolved": "https://registry.npmjs.org/acorn/-/acorn-8.15.0.tgz",
       "integrity": "sha512-NZyJarBfL7nWwIq+FDL6Zp/yHEhePMNnnJ0y3qfieCrmNvYct8uvtiV41UvlSe6apAfk0fY1FbWx+NwfmpvtTg==",
       "license": "MIT",
+      "peer": true,
       "bin": {
         "acorn": "bin/acorn"
       },
@@ -3011,6 +3020,7 @@
       "integrity": "sha512-O0piBKY36YSJhlFSG8p9VUdPV/SxxS4FYDWVpr/9GJuMaepzwlf4J8I4ov1b+ySQfDTPhc3DtLaxcT1fN0yqCg==",
       "dev": true,
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "@eslint-community/eslint-utils": "^4.8.0",
         "@eslint-community/regexpp": "^4.12.2",
@@ -3424,6 +3434,7 @@
       "resolved": "https://registry.npmjs.org/express/-/express-5.2.1.tgz",
       "integrity": "sha512-hIS4idWWai69NezIdRt2xFVofaF4j+6INOpJlVOLDO8zXGpUVEVzIYk12UUi2JzjEzWL3IOAxcTubgz9Po0yXw==",
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "accepts": "^2.0.0",
         "body-parser": "^2.2.1",
@@ -5974,6 +5985,7 @@
       "integrity": "sha512-jl1vZzPDinLr9eUt3J/t7V6FgNEw9QjvBPdysz9KfQDD41fQrC2Y4vKQdiaUpFT4bXlb1RHhLpp8wtm6M5TgSw==",
       "dev": true,
       "license": "Apache-2.0",
+      "peer": true,
       "bin": {
         "tsc": "bin/tsc",
         "tsserver": "bin/tsserver"
@@ -6014,6 +6026,7 @@
       "dev": true,
       "hasInstallScript": true,
       "license": "MIT",
+      "peer": true,
       "dependencies": {
         "napi-postinstall": "^0.3.0"
       },
diff --git a/src/handlers/response-validation.js b/src/handlers/response-validation.js
index 940909d..79dcf80 100644
--- a/src/handlers/response-validation.js
+++ b/src/handlers/response-validation.js
@@ -1,12 +1,10 @@
 export default (logger, validateResponse) => (context, request, response) => {
-  // Prevent sending headers if they're already sent
-  if (response.headersSent) {
-    return undefined
-  }
-
   const responseDoesntNeedValidation = response.statusCode >= 400
   if (responseDoesntNeedValidation) {
-    return response.json(context.response)
+    if (!response.headersSent) {
+      return response.json(context.response)
+    }
+    return context.response
   }
 
   const valid = validateResponse
@@ -27,25 +25,31 @@ export default (logger, validateResponse) => (context, request, response) => {
         response: context.response
       })
     }
+    const errorResponse = {
+      errors: valid.errors,
+      status: 502,
+      timestamp: new Date(),
+      message: 'Bad response'
+    }
     if (!response.headersSent) {
-      return response.status(502).json({
-        errors: valid.errors,
-        status: 502,
-        timestamp: new Date(),
-        message: 'Bad response'
-      })
+      return response.status(502).json(errorResponse)
     }
-    return undefined
+    return errorResponse
   }
 
   if (!context.response) {
-    return response.end()
+    if (!response.headersSent) {
+      return response.end()
+    }
+    return null
   }
 
   const contentType = request?.headers?.accept ?? 'application/json'
-  if (contentType === 'application/json') {
-    return response.json(context.response)
+  if (!response.headersSent) {
+    if (contentType === 'application/json') {
+      return response.json(context.response)
+    }
+    return response.send(context.response)
   }
-
-  return response.send(context.response)
+  return context.response
 }