diff --git a/module-core/src/main/java/io/goobi/vocabulary/api/MaintenanceController.java b/module-core/src/main/java/io/goobi/vocabulary/api/MaintenanceController.java
new file mode 100644
index 0000000..f1303a6
--- /dev/null
+++ b/module-core/src/main/java/io/goobi/vocabulary/api/MaintenanceController.java
@@ -0,0 +1,29 @@
+package io.goobi.vocabulary.api;
+
+import io.goobi.vocabulary.service.manager.MaintenanceManager;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping("/api/v1/maintenance")
+public class MaintenanceController {
+    private final MaintenanceManager maintenanceManager;
+
+    public MaintenanceController(MaintenanceManager maintenanceManager) {
+        this.maintenanceManager = maintenanceManager;
+    }
+
+    @GetMapping("/selfcheck")
+    public ResponseEntity<String> selfCheck() {
+        String status = maintenanceManager.testAllData();
+        if (status.contains("FAIL")) {
+            return ResponseEntity.internalServerError()
+                    .body(status);
+        } else {
+            return ResponseEntity.ok()
+                    .body(status);
+        }
+    }
+}
diff --git a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldDefinitionEntity.java b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldDefinitionEntity.java
index 1504bdb..462c0de 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldDefinitionEntity.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldDefinitionEntity.java
@@ -26,7 +26,7 @@
         })
 @Getter
 @Setter
-public class FieldDefinitionEntity {
+public class FieldDefinitionEntity implements Identifiable {
     @Id
     @GeneratedValue(strategy = GenerationType.AUTO)
     @Column(name = "id", nullable = false)
diff --git a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldInstanceEntity.java b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldInstanceEntity.java
index 0030e33..f4ce67b 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldInstanceEntity.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldInstanceEntity.java
@@ -21,7 +21,7 @@
 @Table(name = "field_instance")
 @Getter
 @Setter
-public class FieldInstanceEntity {
+public class FieldInstanceEntity implements Identifiable {
     private static final int MAX_LANGUAGE_LENGTH = 3;
 
     @Id
diff --git a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldTranslationEntity.java b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldTranslationEntity.java
index 192ac28..4b6fb7a 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldTranslationEntity.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldTranslationEntity.java
@@ -17,7 +17,7 @@
 @Table(name = "field_translation")
 @Getter
 @Setter
-public class FieldTranslationEntity {
+public class FieldTranslationEntity implements Identifiable {
     @Id
     @GeneratedValue(strategy = GenerationType.AUTO)
     @Column(name = "id", nullable = false)
diff --git a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldTypeEntity.java b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldTypeEntity.java
index 5b90f7b..ffffbeb 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldTypeEntity.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldTypeEntity.java
@@ -18,7 +18,7 @@
 @Table(name = "field_type")
 @Getter
 @Setter
-public class FieldTypeEntity {
+public class FieldTypeEntity implements Identifiable {
     @Id
     @GeneratedValue(strategy = GenerationType.AUTO)
     @Column(name = "id", nullable = false)
diff --git a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldValueEntity.java b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldValueEntity.java
index e1956d5..c89061b 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldValueEntity.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/FieldValueEntity.java
@@ -21,7 +21,7 @@
 @Table(name = "field_value")
 @Getter
 @Setter
-public class FieldValueEntity {
+public class FieldValueEntity implements Identifiable {
     @Id
     @GeneratedValue(strategy = GenerationType.AUTO)
     @Column(name = "id", nullable = false)
diff --git a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/Identifiable.java b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/Identifiable.java
new file mode 100644
index 0000000..7abc3b6
--- /dev/null
+++ b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/Identifiable.java
@@ -0,0 +1,5 @@
+package io.goobi.vocabulary.model.jpa;
+
+public interface Identifiable {
+    long getId();
+}
diff --git a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/LanguageEntity.java b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/LanguageEntity.java
index 35bc1fa..60625ea 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/LanguageEntity.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/LanguageEntity.java
@@ -14,7 +14,7 @@
 @Table(name = "language")
 @Getter
 @Setter
-public class LanguageEntity {
+public class LanguageEntity implements Identifiable {
     @Id
     @GeneratedValue(strategy = GenerationType.AUTO)
     @Column(name = "id", nullable = false)
diff --git a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/SelectableValueEntity.java b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/SelectableValueEntity.java
index 298c421..400f51c 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/SelectableValueEntity.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/SelectableValueEntity.java
@@ -16,7 +16,7 @@
 @Table(name = "selectable_value")
 @Getter
 @Setter
-public class SelectableValueEntity {
+public class SelectableValueEntity implements Identifiable {
     @Id
     @GeneratedValue(strategy = GenerationType.AUTO)
     @Column(name = "id", nullable = false)
diff --git a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/TranslationDefinitionEntity.java b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/TranslationDefinitionEntity.java
index 1f53642..1988ba5 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/TranslationDefinitionEntity.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/TranslationDefinitionEntity.java
@@ -20,7 +20,7 @@
         })
 @Getter
 @Setter
-public class TranslationDefinitionEntity {
+public class TranslationDefinitionEntity implements Identifiable {
     @Id
     @GeneratedValue(strategy = GenerationType.AUTO)
     @Column(name = "id", nullable = false)
diff --git a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/VocabularyEntity.java b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/VocabularyEntity.java
index 1086c89..d1187eb 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/VocabularyEntity.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/VocabularyEntity.java
@@ -20,7 +20,7 @@
 @Table(name = "vocabulary")
 @Getter
 @Setter
-public class VocabularyEntity {
+public class VocabularyEntity implements Identifiable {
     @Id
     @GeneratedValue(strategy = GenerationType.AUTO)
     @Column(name = "id", nullable = false)
diff --git a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/VocabularyRecordEntity.java b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/VocabularyRecordEntity.java
index 8966639..c9cb76c 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/VocabularyRecordEntity.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/VocabularyRecordEntity.java
@@ -23,7 +23,7 @@
 @Getter
 @Setter
 // Naming this class `Record` led to wrong behavior because of the introduction of Java records and some Spring Boot JPA logic
-public class VocabularyRecordEntity {
+public class VocabularyRecordEntity implements Identifiable {
     @Id
     @GeneratedValue(strategy = GenerationType.AUTO)
     @Column(name = "id", nullable = false)
diff --git a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/VocabularySchemaEntity.java b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/VocabularySchemaEntity.java
index d86dbae..cb780f6 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/model/jpa/VocabularySchemaEntity.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/model/jpa/VocabularySchemaEntity.java
@@ -18,7 +18,7 @@
 @Table(name = "vocabulary_schema")
 @Getter
 @Setter
-public class VocabularySchemaEntity {
+public class VocabularySchemaEntity implements Identifiable {
     @Id
     @GeneratedValue(strategy = GenerationType.AUTO)
     @Column(name = "id", nullable = false)
diff --git a/module-core/src/main/java/io/goobi/vocabulary/repositories/FieldTypeRepository.java b/module-core/src/main/java/io/goobi/vocabulary/repositories/FieldTypeRepository.java
index bec71a5..f68b5bd 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/repositories/FieldTypeRepository.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/repositories/FieldTypeRepository.java
@@ -3,12 +3,12 @@
 import io.goobi.vocabulary.model.jpa.FieldTypeEntity;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
-import org.springframework.data.repository.CrudRepository;
+import org.springframework.data.repository.ListCrudRepository;
 import org.springframework.lang.NonNull;
 
 import java.util.Optional;
 
-public interface FieldTypeRepository extends CrudRepository<FieldTypeEntity, Long> {
+public interface FieldTypeRepository extends ListCrudRepository<FieldTypeEntity, Long> {
     Page<FieldTypeEntity> findAll(Pageable pageable);
 
     Optional<FieldTypeEntity> findByName(@NonNull String name);
diff --git a/module-core/src/main/java/io/goobi/vocabulary/repositories/LanguageRepository.java b/module-core/src/main/java/io/goobi/vocabulary/repositories/LanguageRepository.java
index fa04f21..f95345b 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/repositories/LanguageRepository.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/repositories/LanguageRepository.java
@@ -3,12 +3,12 @@
 import io.goobi.vocabulary.model.jpa.LanguageEntity;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
-import org.springframework.data.repository.CrudRepository;
+import org.springframework.data.repository.ListCrudRepository;
 import org.springframework.lang.NonNull;
 
 import java.util.Optional;
 
-public interface LanguageRepository extends CrudRepository<LanguageEntity, Long> {
+public interface LanguageRepository extends ListCrudRepository<LanguageEntity, Long> {
     Optional<LanguageEntity> findByAbbreviation(@NonNull String abbreviation);
 
     Page<LanguageEntity> findAll(Pageable pageable);
diff --git a/module-core/src/main/java/io/goobi/vocabulary/repositories/VocabularyRecordRepository.java b/module-core/src/main/java/io/goobi/vocabulary/repositories/VocabularyRecordRepository.java
index 08704d0..f3c1e3a 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/repositories/VocabularyRecordRepository.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/repositories/VocabularyRecordRepository.java
@@ -4,13 +4,13 @@
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.jpa.repository.Query;
-import org.springframework.data.repository.CrudRepository;
+import org.springframework.data.repository.ListCrudRepository;
 import org.springframework.lang.NonNull;
 
 import java.util.List;
 import java.util.Optional;
 
-public interface VocabularyRecordRepository extends CrudRepository<VocabularyRecordEntity, Long> {
+public interface VocabularyRecordRepository extends ListCrudRepository<VocabularyRecordEntity, Long> {
     @Override
     Optional<VocabularyRecordEntity> findById(Long aLong);
 
diff --git a/module-core/src/main/java/io/goobi/vocabulary/service/exchange/DTOMapperImpl.java b/module-core/src/main/java/io/goobi/vocabulary/service/exchange/DTOMapperImpl.java
index f1d9c33..1273e03 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/service/exchange/DTOMapperImpl.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/service/exchange/DTOMapperImpl.java
@@ -1,6 +1,5 @@
 package io.goobi.vocabulary.service.exchange;
 
-import io.goobi.vocabulary.api.assemblers.RecordAssembler;
 import io.goobi.vocabulary.exception.EntityNotFoundException;
 import io.goobi.vocabulary.exception.MissingAttributeException;
 import io.goobi.vocabulary.exchange.FieldDefinition;
diff --git a/module-core/src/main/java/io/goobi/vocabulary/service/manager/MaintenanceManager.java b/module-core/src/main/java/io/goobi/vocabulary/service/manager/MaintenanceManager.java
new file mode 100644
index 0000000..abfc4e5
--- /dev/null
+++ b/module-core/src/main/java/io/goobi/vocabulary/service/manager/MaintenanceManager.java
@@ -0,0 +1,83 @@
+package io.goobi.vocabulary.service.manager;
+
+import io.goobi.vocabulary.exception.VocabularyException;
+import io.goobi.vocabulary.model.jpa.FieldTypeEntity;
+import io.goobi.vocabulary.model.jpa.VocabularyEntity;
+import io.goobi.vocabulary.model.jpa.VocabularyRecordEntity;
+import io.goobi.vocabulary.model.jpa.VocabularySchemaEntity;
+import io.goobi.vocabulary.repositories.FieldTypeRepository;
+import io.goobi.vocabulary.repositories.VocabularyRecordRepository;
+import io.goobi.vocabulary.repositories.VocabularyRepository;
+import io.goobi.vocabulary.repositories.VocabularySchemaRepository;
+import io.goobi.vocabulary.validation.Validator;
+import org.springframework.data.repository.ListCrudRepository;
+import org.springframework.stereotype.Service;
+
+import java.util.LinkedList;
+import java.util.List;
+
+@Service
+public class MaintenanceManager {
+    private final FieldTypeRepository fieldTypeRepository;
+    private final VocabularyRepository vocabularyRepository;
+    private final VocabularySchemaRepository vocabularySchemaRepository;
+    private final VocabularyRecordRepository vocabularyRecordRepository;
+
+    private final Validator<FieldTypeEntity> fieldTypeValidator;
+    private final Validator<VocabularyEntity> vocabularyValidator;
+    private final Validator<VocabularySchemaEntity> vocabularySchemaValidator;
+    private final Validator<VocabularyRecordEntity> vocabularyRecordValidator;
+
+    public MaintenanceManager(FieldTypeRepository fieldTypeRepository, VocabularyRepository vocabularyRepository, VocabularySchemaRepository vocabularySchemaRepository, VocabularyRecordRepository vocabularyRecordRepository, Validator<FieldTypeEntity> fieldTypeValidator, Validator<VocabularyEntity> vocabularyValidator, Validator<VocabularySchemaEntity> vocabularySchemaValidator, Validator<VocabularyRecordEntity> vocabularyRecordValidator) {
+        this.fieldTypeRepository = fieldTypeRepository;
+        this.vocabularyRepository = vocabularyRepository;
+        this.vocabularyValidator = vocabularyValidator;
+        this.vocabularySchemaRepository = vocabularySchemaRepository;
+        this.vocabularyRecordRepository = vocabularyRecordRepository;
+        this.fieldTypeValidator = fieldTypeValidator;
+        this.vocabularySchemaValidator = vocabularySchemaValidator;
+        this.vocabularyRecordValidator = vocabularyRecordValidator;
+    }
+
+    public String testAllData() {
+        List<String> selfCheckResults = new LinkedList<>();
+
+        selfCheckResults.add(selfTest("Types", fieldTypeRepository, fieldTypeValidator));
+        selfCheckResults.add(selfTest("Vocabularies", vocabularyRepository, vocabularyValidator));
+        selfCheckResults.add(selfTest("Vocabulary Schemas", vocabularySchemaRepository, vocabularySchemaValidator));
+        selfCheckResults.add(selfTest("Vocabulary Records", vocabularyRecordRepository, vocabularyRecordValidator));
+
+        return String.join("\n", selfCheckResults);
+    }
+
+
+    private <Entity> String selfTest(String entityName, ListCrudRepository<Entity, Long> repo, Validator<Entity> validator) {
+        List<String> errors = new LinkedList<>();
+        for (Entity entity : repo.findAll()) {
+            try {
+                validator.validate(entity);
+            } catch (VocabularyException e) {
+                errors.add(dumpException(e, 1));
+            }
+        }
+        if (errors.isEmpty()) {
+            return entityName + ": OK";
+        } else {
+            return entityName + ": FAIL"
+                    + String.join("", errors);
+        }
+    }
+
+    private String dumpException(VocabularyException ex, int level) {
+        StringBuilder s = new StringBuilder();
+        s.append('\n')
+                .append("\t".repeat(level))
+                .append(ex.getMessage());
+        if (ex.getCauses() != null) {
+            for (VocabularyException c : ex.getCauses()) {
+                s.append(dumpException(c, level + 1));
+            }
+        }
+        return s.toString();
+    }
+}
diff --git a/module-core/src/main/java/io/goobi/vocabulary/validation/BaseValidator.java b/module-core/src/main/java/io/goobi/vocabulary/validation/BaseValidator.java
index b6c633e..a594763 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/validation/BaseValidator.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/validation/BaseValidator.java
@@ -1,6 +1,7 @@
 package io.goobi.vocabulary.validation;
 
 import io.goobi.vocabulary.exception.VocabularyException;
+import io.goobi.vocabulary.model.jpa.Identifiable;
 import lombok.Setter;
 
 import java.util.LinkedList;
@@ -8,7 +9,7 @@
 
 import static io.goobi.vocabulary.exception.VocabularyException.ErrorCode.GenericValidation;
 
-public class BaseValidator<T> implements Validator<T> {
+public class BaseValidator<T extends Identifiable> implements Validator<T> {
     private final String name;
     @Setter
     private List<ValidationMethod<T>> validations;
@@ -28,7 +29,7 @@ public final void validate(T t) throws VocabularyException {
             }
         }
         if (!errors.isEmpty()) {
-            throw new VocabularyException(GenericValidation, errors, null, (params) -> "Validation error");
+            throw new VocabularyException(GenericValidation, errors, null, (params) -> "Validation error [" + t.getId() + "]");
         }
     }
 }
diff --git a/module-core/src/main/java/io/goobi/vocabulary/validation/RecordValidatorImpl.java b/module-core/src/main/java/io/goobi/vocabulary/validation/RecordValidatorImpl.java
index 9f3be01..091c78b 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/validation/RecordValidatorImpl.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/validation/RecordValidatorImpl.java
@@ -67,7 +67,7 @@ private void checkRequiredFieldsExistence(VocabularyRecordEntity vocabularyRecor
                             .map(FieldDefinitionEntity::getName)
                             .collect(Collectors.joining(","))
             ),
-                    params -> "Missing required fields: " + params.get("missingFields")
+                    params -> "Missing required fields: " + params.get("missingFieldNames")
             );
         }
     }
diff --git a/module-core/src/main/java/io/goobi/vocabulary/validation/SchemaValidatorImpl.java b/module-core/src/main/java/io/goobi/vocabulary/validation/SchemaValidatorImpl.java
index ae531bb..b1c19b1 100644
--- a/module-core/src/main/java/io/goobi/vocabulary/validation/SchemaValidatorImpl.java
+++ b/module-core/src/main/java/io/goobi/vocabulary/validation/SchemaValidatorImpl.java
@@ -14,7 +14,6 @@
 import static io.goobi.vocabulary.exception.VocabularyException.ErrorCode.SchemaValidationMainFieldIsNotRequired;
 import static io.goobi.vocabulary.exception.VocabularyException.ErrorCode.SchemaValidationMissingMainField;
 import static io.goobi.vocabulary.exception.VocabularyException.ErrorCode.SchemaValidationNoDefinitions;
-import static io.goobi.vocabulary.exception.VocabularyException.ErrorCode.SchemaValidationTitleFieldsAreNotRequired;
 import static io.goobi.vocabulary.exception.VocabularyException.ErrorCode.SchemaValidationTooManyMainFields;
 
 @Service