diff --git a/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/SpringDocITest.kt b/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/SpringDocITest.kt
index d95562daf..adbbe8084 100644
--- a/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/SpringDocITest.kt
+++ b/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/SpringDocITest.kt
@@ -5,6 +5,7 @@ import org.junit.jupiter.api.Test
 import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc
 import org.springframework.boot.test.context.SpringBootTest
+import org.springframework.http.MediaType
 import org.springframework.test.context.ActiveProfiles
 import org.springframework.test.web.servlet.MockMvc
 import org.springframework.test.web.servlet.result.MockMvcResultMatchers.content
@@ -19,7 +20,7 @@ class SpringdocITest(@Autowired override val mockMvc: MockMvc) : ControllerTest,
 
     @Test
     fun `Should display Swagger UI page`() {
-        get("/swagger-ui/index.html")
+        get("/swagger-ui/index.html", resultType = MediaType.TEXT_HTML)
             .andExpect(status().isOk())
             .andExpect(content().string(containsString("Swagger UI")))
     }
diff --git a/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/application/ApplicationControllerITest.kt b/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/application/ApplicationControllerITest.kt
index 6d87e95c3..1b525591c 100644
--- a/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/application/ApplicationControllerITest.kt
+++ b/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/application/ApplicationControllerITest.kt
@@ -695,7 +695,7 @@ class ApplicationControllerITest(@Autowired override val mockMvc: MockMvc) : Con
         val id = 11L
         every { applicationService.getApplicationById(id) } throws ApplicationNotFoundException(id)
 
-        get("$BASE_URL/$id/paatos", APPLICATION_PDF, APPLICATION_JSON)
+        get("$BASE_URL/$id/paatos", accept = arrayOf(APPLICATION_PDF, APPLICATION_JSON))
             .andExpect(status().isNotFound)
             .andExpect(content().contentType(APPLICATION_JSON))
             .andExpect(jsonPath("errorCode").value("HAI2001"))
@@ -715,7 +715,7 @@ class ApplicationControllerITest(@Autowired override val mockMvc: MockMvc) : Con
         every { applicationService.downloadDecision(id, USERNAME) } throws
             ApplicationDecisionNotFoundException("Decision not found in Allu. alluid=23")
 
-        get("$BASE_URL/11/paatos", APPLICATION_PDF, APPLICATION_JSON)
+        get("$BASE_URL/11/paatos", accept = arrayOf(APPLICATION_PDF, APPLICATION_JSON))
             .andExpect(status().isNotFound)
             .andExpect(content().contentType(APPLICATION_JSON))
             .andExpect(jsonPath("errorCode").value("HAI2006"))
@@ -737,7 +737,11 @@ class ApplicationControllerITest(@Autowired override val mockMvc: MockMvc) : Con
         every { applicationService.downloadDecision(11, USERNAME) } returns
             Pair("JS230001", pdfBytes)
 
-        get("$BASE_URL/11/paatos", APPLICATION_PDF, APPLICATION_JSON)
+        get(
+                "$BASE_URL/11/paatos",
+                resultType = APPLICATION_PDF,
+                accept = arrayOf(APPLICATION_PDF, APPLICATION_JSON)
+            )
             .andExpect(status().isOk)
             .andExpect(header().string("Content-Disposition", "inline; filename=JS230001.pdf"))
             .andExpect(content().contentType(APPLICATION_PDF))
@@ -757,7 +761,7 @@ class ApplicationControllerITest(@Autowired override val mockMvc: MockMvc) : Con
             AlluDataFactory.createApplication(id = id, hankeTunnus = HANKE_TUNNUS)
         every { permissionService.hasPermission(42, USERNAME, VIEW) } returns false
 
-        get("$BASE_URL/$id/paatos", APPLICATION_PDF, APPLICATION_JSON)
+        get("$BASE_URL/$id/paatos", accept = arrayOf(APPLICATION_PDF, APPLICATION_JSON))
             .andExpect(status().isNotFound)
 
         verify { applicationService.getApplicationById(id) }
diff --git a/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/attachment/AttachmentTestUtil.kt b/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/attachment/AttachmentTestUtil.kt
index 5a6775a6a..6a13c4095 100644
--- a/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/attachment/AttachmentTestUtil.kt
+++ b/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/attachment/AttachmentTestUtil.kt
@@ -5,6 +5,7 @@ import fi.hel.haitaton.hanke.attachment.common.FileResult
 import fi.hel.haitaton.hanke.attachment.common.FileScanData
 import fi.hel.haitaton.hanke.attachment.common.FileScanResponse
 import fi.hel.haitaton.hanke.getResourceAsBytes
+import fi.hel.haitaton.hanke.hankeError
 import fi.hel.haitaton.hanke.toJsonString
 import okhttp3.mockwebserver.MockResponse
 import org.springframework.http.MediaType.APPLICATION_JSON_VALUE
@@ -12,7 +13,6 @@ import org.springframework.http.MediaType.APPLICATION_PDF_VALUE
 import org.springframework.mock.web.MockMultipartFile
 import org.springframework.security.test.web.servlet.response.SecurityMockMvcResultMatchers.unauthenticated
 import org.springframework.test.web.servlet.ResultActions
-import org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath
 import org.springframework.test.web.servlet.result.MockMvcResultMatchers.status
 
 const val USERNAME = "username"
@@ -34,10 +34,7 @@ fun testFile(
 ) = MockMultipartFile(fileParam, fileName, contentType, data)
 
 fun ResultActions.andExpectError(error: HankeError): ResultActions =
-    andExpect(unauthenticated())
-        .andExpect(status().isUnauthorized)
-        .andExpect(jsonPath("$.errorCode").value(error.errorCode))
-        .andExpect(jsonPath("$.errorMessage").value(error.errorMessage))
+    andExpect(unauthenticated()).andExpect(status().isUnauthorized).andExpect(hankeError(error))
 
 fun response(data: String): MockResponse =
     MockResponse()
diff --git a/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/attachment/application/ApplicationAttachmentControllerITest.kt b/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/attachment/application/ApplicationAttachmentControllerITest.kt
index bd5264e5b..4a781efa7 100644
--- a/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/attachment/application/ApplicationAttachmentControllerITest.kt
+++ b/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/attachment/application/ApplicationAttachmentControllerITest.kt
@@ -46,6 +46,8 @@ import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest
 import org.springframework.context.annotation.Import
 import org.springframework.http.HttpHeaders.CONTENT_DISPOSITION
+import org.springframework.http.MediaType
+import org.springframework.http.MediaType.APPLICATION_JSON
 import org.springframework.http.MediaType.APPLICATION_PDF
 import org.springframework.http.MediaType.APPLICATION_PDF_VALUE
 import org.springframework.mock.web.MockMultipartFile
@@ -130,7 +132,6 @@ class ApplicationAttachmentControllerITest(@Autowired override val mockMvc: Mock
         getAttachmentContent(attachmentId = attachmentId)
             .andExpect(status().isOk)
             .andExpect(header().string(CONTENT_DISPOSITION, "attachment; filename=$FILE_NAME_PDF"))
-            .andExpect(content().contentType(APPLICATION_PDF))
             .andExpect(content().bytes(dummyData))
 
         verifyOrder {
@@ -256,7 +257,7 @@ class ApplicationAttachmentControllerITest(@Autowired override val mockMvc: Mock
     @WithAnonymousUser
     fun `unauthorized without authenticated user`() {
         getMetadataList().andExpectError(HAI0001)
-        getAttachmentContent().andExpectError(HAI0001)
+        getAttachmentContent(resultType = APPLICATION_JSON).andExpectError(HAI0001)
         postAttachment().andExpectError(HAI0001)
         deleteAttachment().andExpectError(HAI0001)
     }
@@ -267,7 +268,9 @@ class ApplicationAttachmentControllerITest(@Autowired override val mockMvc: Mock
     private fun getAttachmentContent(
         applicationId: Long = APPLICATION_ID,
         attachmentId: UUID = randomUUID(),
-    ): ResultActions = get("/hakemukset/$applicationId/liitteet/$attachmentId/content")
+        resultType: MediaType = APPLICATION_PDF,
+    ): ResultActions =
+        get("/hakemukset/$applicationId/liitteet/$attachmentId/content", resultType = resultType)
 
     private fun postAttachment(
         applicationId: Long = APPLICATION_ID,
diff --git a/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/attachment/hanke/HankeAttachmentControllerITests.kt b/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/attachment/hanke/HankeAttachmentControllerITests.kt
index 61d170121..74c8ec2d3 100644
--- a/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/attachment/hanke/HankeAttachmentControllerITests.kt
+++ b/services/hanke-service/src/integrationTest/kotlin/fi/hel/haitaton/hanke/attachment/hanke/HankeAttachmentControllerITests.kt
@@ -35,6 +35,8 @@ import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest
 import org.springframework.context.annotation.Import
 import org.springframework.http.HttpHeaders.CONTENT_DISPOSITION
+import org.springframework.http.MediaType
+import org.springframework.http.MediaType.APPLICATION_JSON
 import org.springframework.http.MediaType.APPLICATION_PDF
 import org.springframework.http.MediaType.APPLICATION_PDF_VALUE
 import org.springframework.mock.web.MockMultipartFile
@@ -167,7 +169,7 @@ class HankeAttachmentControllerITests(@Autowired override val mockMvc: MockMvc)
     @WithAnonymousUser
     fun `unauthorized without authenticated user`() {
         getMetadataList().andExpectError(HAI0001)
-        getAttachmentContent().andExpectError(HAI0001)
+        getAttachmentContent(resultType = APPLICATION_JSON).andExpectError(HAI0001)
         postAttachment().andExpectError(HAI0001)
         deleteAttachment().andExpectError(HAI0001)
     }
@@ -178,7 +180,9 @@ class HankeAttachmentControllerITests(@Autowired override val mockMvc: MockMvc)
     private fun getAttachmentContent(
         hankeTunnus: String = HANKE_TUNNUS,
         attachmentId: UUID = randomUUID(),
-    ): ResultActions = get("/hankkeet/$hankeTunnus/liitteet/$attachmentId/content")
+        resultType: MediaType = APPLICATION_PDF,
+    ): ResultActions =
+        get("/hankkeet/$hankeTunnus/liitteet/$attachmentId/content", resultType = resultType)
 
     private fun postAttachment(
         hankeTunnus: String = HANKE_TUNNUS,
diff --git a/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/HankeController.kt b/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/HankeController.kt
index 3a0ca9b36..e93e622f0 100644
--- a/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/HankeController.kt
+++ b/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/HankeController.kt
@@ -21,7 +21,6 @@ import jakarta.validation.ConstraintViolationException
 import mu.KotlinLogging
 import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.http.HttpStatus
-import org.springframework.http.MediaType.APPLICATION_JSON_VALUE
 import org.springframework.validation.annotation.Validated
 import org.springframework.web.bind.annotation.DeleteMapping
 import org.springframework.web.bind.annotation.ExceptionHandler
@@ -48,7 +47,7 @@ class HankeController(
     @Autowired private val featureFlags: FeatureFlags,
 ) {
 
-    @GetMapping("/{hankeTunnus}", produces = [APPLICATION_JSON_VALUE])
+    @GetMapping("/{hankeTunnus}")
     @Operation(summary = "Get hanke", description = "Get specific hanke by hankeTunnus.")
     @ApiResponses(
         value =
@@ -77,7 +76,7 @@ class HankeController(
         return hanke
     }
 
-    @GetMapping(produces = [APPLICATION_JSON_VALUE])
+    @GetMapping
     @Operation(
         summary = "Get hanke list",
         description =
@@ -124,7 +123,7 @@ class HankeController(
         return hankeList
     }
 
-    @GetMapping("/{hankeTunnus}/hakemukset", produces = [APPLICATION_JSON_VALUE])
+    @GetMapping("/{hankeTunnus}/hakemukset")
     @Operation(
         summary = "Get hanke applications",
         description = "Returns list of applications belonging to a given hanke."
@@ -148,7 +147,7 @@ class HankeController(
         }
     }
 
-    @PostMapping(consumes = [APPLICATION_JSON_VALUE], produces = [APPLICATION_JSON_VALUE])
+    @PostMapping
     @Operation(
         summary = "Create new hanke",
         description =
@@ -194,11 +193,7 @@ When Hanke is created:
         return createdHanke
     }
 
-    @PutMapping(
-        "/{hankeTunnus}",
-        consumes = [APPLICATION_JSON_VALUE],
-        produces = [APPLICATION_JSON_VALUE]
-    )
+    @PutMapping("/{hankeTunnus}")
     @Operation(
         summary = "Update hanke",
         description =
diff --git a/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/PublicHankeController.kt b/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/PublicHankeController.kt
index b11dc7354..037fda04e 100644
--- a/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/PublicHankeController.kt
+++ b/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/PublicHankeController.kt
@@ -8,7 +8,6 @@ import io.swagger.v3.oas.annotations.media.Content
 import io.swagger.v3.oas.annotations.media.Schema
 import io.swagger.v3.oas.annotations.responses.ApiResponse
 import io.swagger.v3.oas.annotations.responses.ApiResponses
-import org.springframework.http.MediaType.APPLICATION_JSON_VALUE
 import org.springframework.web.bind.annotation.GetMapping
 import org.springframework.web.bind.annotation.RequestMapping
 import org.springframework.web.bind.annotation.RestController
@@ -17,7 +16,7 @@ import org.springframework.web.bind.annotation.RestController
 @RequestMapping("/public-hankkeet")
 class PublicHankeController(private val hankeService: HankeService) {
 
-    @GetMapping(produces = [APPLICATION_JSON_VALUE])
+    @GetMapping
     @Operation(
         summary = "Get list of public hanke",
         description =
diff --git a/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/permissions/HankeKayttajaController.kt b/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/permissions/HankeKayttajaController.kt
index 9a6fd5095..efbab06dd 100644
--- a/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/permissions/HankeKayttajaController.kt
+++ b/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/permissions/HankeKayttajaController.kt
@@ -16,7 +16,6 @@ import io.swagger.v3.oas.annotations.responses.ApiResponses
 import io.swagger.v3.oas.annotations.security.SecurityRequirement
 import mu.KotlinLogging
 import org.springframework.http.HttpStatus
-import org.springframework.http.MediaType.APPLICATION_JSON_VALUE
 import org.springframework.web.bind.annotation.ExceptionHandler
 import org.springframework.web.bind.annotation.GetMapping
 import org.springframework.web.bind.annotation.PathVariable
@@ -38,7 +37,7 @@ class HankeKayttajaController(
     private val featureFlags: FeatureFlags,
 ) {
 
-    @GetMapping("/hankkeet/{hankeTunnus}/kayttajat", produces = [APPLICATION_JSON_VALUE])
+    @GetMapping("/hankkeet/{hankeTunnus}/kayttajat")
     @Operation(
         summary = "Get Hanke users",
         description = "Returns a list of users and their Hanke related information."
diff --git a/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/security/AccessRules.kt b/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/security/AccessRules.kt
index c174f531e..8ae259aad 100644
--- a/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/security/AccessRules.kt
+++ b/services/hanke-service/src/main/kotlin/fi/hel/haitaton/hanke/security/AccessRules.kt
@@ -6,6 +6,7 @@ import io.sentry.Sentry
 import jakarta.servlet.http.HttpServletResponse
 import mu.KotlinLogging
 import org.springframework.http.HttpMethod
+import org.springframework.http.MediaType.APPLICATION_JSON_VALUE
 import org.springframework.security.config.annotation.web.builders.HttpSecurity
 
 private val logger = KotlinLogging.logger {}
@@ -45,6 +46,7 @@ object AccessRules {
                 Sentry.captureException(authenticationException)
                 response.writer.print(OBJECT_MAPPER.writeValueAsString(HankeError.HAI0001))
                 response.status = HttpServletResponse.SC_UNAUTHORIZED
+                response.contentType = APPLICATION_JSON_VALUE
             }
     }
 }
diff --git a/services/hanke-service/src/test/kotlin/fi/hel/haitaton/hanke/ControllerTest.kt b/services/hanke-service/src/test/kotlin/fi/hel/haitaton/hanke/ControllerTest.kt
index 76ca09ed9..cf04b1541 100644
--- a/services/hanke-service/src/test/kotlin/fi/hel/haitaton/hanke/ControllerTest.kt
+++ b/services/hanke-service/src/test/kotlin/fi/hel/haitaton/hanke/ControllerTest.kt
@@ -6,6 +6,7 @@ import org.springframework.test.web.servlet.MockMvc
 import org.springframework.test.web.servlet.ResultActions
 import org.springframework.test.web.servlet.request.MockHttpServletRequestBuilder
 import org.springframework.test.web.servlet.request.MockMvcRequestBuilders
+import org.springframework.test.web.servlet.result.MockMvcResultMatchers.content
 
 interface ControllerTest {
     val mockMvc: MockMvc
@@ -13,9 +14,12 @@ interface ControllerTest {
     /** Send a GET request to the given URL. */
     fun get(
         url: String,
-        vararg accept: MediaType = arrayOf(MediaType.APPLICATION_JSON)
+        resultType: MediaType = MediaType.APPLICATION_JSON,
+        accept: Array<MediaType> = arrayOf(MediaType.APPLICATION_JSON)
     ): ResultActions {
-        return mockMvc.perform(MockMvcRequestBuilders.get(url).accept(*accept))
+        return mockMvc
+            .perform(MockMvcRequestBuilders.get(url).accept(*accept))
+            .andExpect(content().contentType(resultType))
     }
 
     /**