diff --git a/.DS_Store b/.DS_Store
new file mode 100644
index 0000000..cb2845b
Binary files /dev/null and b/.DS_Store differ
diff --git a/spec/.DS_Store b/spec/.DS_Store
new file mode 100644
index 0000000..b9c7676
Binary files /dev/null and b/spec/.DS_Store differ
diff --git a/spec/components/parameters/fromDate.yaml b/spec/components/parameters/fromDate.yaml
index 65aefcc..da14c64 100644
--- a/spec/components/parameters/fromDate.yaml
+++ b/spec/components/parameters/fromDate.yaml
@@ -4,4 +4,4 @@ description: Start date of the query range in ISO format. Must be within 48 hour
 example: "2019-11-15T08:00:00Z"
 required: true
 schema:
-  type: ISO string
+  type: ISO string (UTC time)
diff --git a/spec/components/parameters/toDate.yaml b/spec/components/parameters/toDate.yaml
index 8a8044b..c827c07 100644
--- a/spec/components/parameters/toDate.yaml
+++ b/spec/components/parameters/toDate.yaml
@@ -5,4 +5,4 @@ description: |
 example: "2019-11-16T08:00:00Z"
 required: true
 schema:
-  type: ISO string
+  type: ISO string (UTC time)
diff --git a/spec/components/schemas/objects/BatteryVoltage.yaml b/spec/components/schemas/objects/BatteryVoltage.yaml
new file mode 100644
index 0000000..dacf580
--- /dev/null
+++ b/spec/components/schemas/objects/BatteryVoltage.yaml
@@ -0,0 +1,10 @@
+type: object
+properties:
+  messageId:
+    $ref: "#/components/schemas/messageId"
+  asset:
+    $ref: "#/components/schemas/asset"
+  recordedAt:
+    $ref: "#/components/schemas/recordedAt"
+  voltage:
+    $ref: "#/components/schemas/voltage"
diff --git a/spec/components/schemas/objects/BatteryVoltageArray.yaml b/spec/components/schemas/objects/BatteryVoltageArray.yaml
new file mode 100644
index 0000000..26be872
--- /dev/null
+++ b/spec/components/schemas/objects/BatteryVoltageArray.yaml
@@ -0,0 +1,3 @@
+type: array
+items:
+  $ref: "#/components/schemas/BatteryVoltage"
diff --git a/spec/components/schemas/objects/CombinedMileage.yaml b/spec/components/schemas/objects/CombinedMileage.yaml
new file mode 100644
index 0000000..ff9fcc4
--- /dev/null
+++ b/spec/components/schemas/objects/CombinedMileage.yaml
@@ -0,0 +1,6 @@
+type: object
+properties:
+  GPSMileage: 
+    $ref: "#/components/schemas/Mileage"
+  mileage:
+    $ref: "#/components/schemas/Mileage"
\ No newline at end of file
diff --git a/spec/components/schemas/objects/DTC.yaml b/spec/components/schemas/objects/DTC.yaml
new file mode 100644
index 0000000..cc66f1c
--- /dev/null
+++ b/spec/components/schemas/objects/DTC.yaml
@@ -0,0 +1,10 @@
+type: object
+properties:
+  messageId:
+    $ref: "#/components/schemas/messageId"
+  asset:
+    $ref: "#/components/schemas/asset"
+  recordedAt:
+    $ref: "#/components/schemas/recordedAt"
+  rawData:
+    $ref: "#/components/schemas/rawData"
diff --git a/spec/components/schemas/objects/DTCArray.yaml b/spec/components/schemas/objects/DTCArray.yaml
new file mode 100644
index 0000000..d49ead9
--- /dev/null
+++ b/spec/components/schemas/objects/DTCArray.yaml
@@ -0,0 +1,3 @@
+type: array
+items:
+  $ref: "#/components/schemas/DTC"
diff --git a/spec/components/schemas/objects/Vin.yaml b/spec/components/schemas/objects/Vin.yaml
new file mode 100644
index 0000000..f3e35c2
--- /dev/null
+++ b/spec/components/schemas/objects/Vin.yaml
@@ -0,0 +1,10 @@
+type: object
+properties:
+  messageId:
+    $ref: "#/components/schemas/messageId"
+  asset:
+    $ref: "#/components/schemas/asset"
+  recordedAt:
+    $ref: "#/components/schemas/recordedAt"
+  vin:
+    $ref: "#/components/schemas/vin"
diff --git a/spec/components/schemas/objects/VinArray.yaml b/spec/components/schemas/objects/VinArray.yaml
new file mode 100644
index 0000000..2b1dd48
--- /dev/null
+++ b/spec/components/schemas/objects/VinArray.yaml
@@ -0,0 +1,3 @@
+type: array
+items:
+  $ref: "#/components/schemas/Vin"
diff --git a/spec/components/schemas/rawData.yaml b/spec/components/schemas/rawData.yaml
new file mode 100644
index 0000000..5f46f1e
--- /dev/null
+++ b/spec/components/schemas/rawData.yaml
@@ -0,0 +1,3 @@
+type: string
+description: Raw DTC code information in stringified JSON format.
+example: [{\"mode\":3,\"ecu\":\"7E8\",\"dtc\":\"U11F5\"}]
\ No newline at end of file
diff --git a/spec/components/schemas/vin.yaml b/spec/components/schemas/vin.yaml
new file mode 100644
index 0000000..2c92a09
--- /dev/null
+++ b/spec/components/schemas/vin.yaml
@@ -0,0 +1,3 @@
+description: Vehicle Identification Number (VIN) of the car
+type: string
+example: WP0ZZZ99ZTS392124
diff --git a/spec/components/schemas/voltage.yaml b/spec/components/schemas/voltage.yaml
new file mode 100644
index 0000000..1b744ca
--- /dev/null
+++ b/spec/components/schemas/voltage.yaml
@@ -0,0 +1,3 @@
+type: double
+description: Battery voltage of the car's battery
+example: 12.09
\ No newline at end of file
diff --git a/spec/openapi.yaml b/spec/openapi.yaml
index 74b36f1..d377998 100644
--- a/spec/openapi.yaml
+++ b/spec/openapi.yaml
@@ -27,10 +27,37 @@ tags:
   - name: Fuel
     description: Get current and historical fuel information for an IMEI.
   - name: Mileage
-    description: Get current and historical mileage information for an IMEI.
+    description: Get current and historical mileage information for an IMEI. \
+      You will find two values here, the mileage reported by the vehicle (`Mileage`) and mileage calculated by the autoSense device (`GPS Mileage`)
   - name: PlugUnplug
     description: |
       Retrieve actual or historical information whether the MDI device is connected to the car's OBD port. \ 
       A new record is created each time the status of the devices changes from `plugged` or `unplugged`.
+  - name: Error Codes
+    description: |
+      Error codes reported by the vehicle and malfunction indicator light status (MIL).
 servers:
   - url: 'https://nebula.service.autosense.ch/api/v1'
+
+x-tagGroups:
+  - name: VIN
+    tags: 
+      - VIN
+  - name: Plug Unplug
+    tags:
+      - PlugUnplug
+  - name: Fuel
+    tags:
+      - Fuel
+  - name: Mileage
+    tags:
+      - Mileage
+      - GPS Mileage
+      - Combined Mileage
+  - name: Error Codes
+    tags:
+      - DTC
+      - MIL
+  - name: Battery Voltage
+    tags:
+      - Battery Voltage
diff --git a/spec/paths/asset@{assetId}@batteryVoltage.yaml b/spec/paths/asset@{assetId}@batteryVoltage.yaml
new file mode 100644
index 0000000..d9be294
--- /dev/null
+++ b/spec/paths/asset@{assetId}@batteryVoltage.yaml
@@ -0,0 +1,28 @@
+parameters:
+  - $ref: "#/components/parameters/assetId"
+
+get:
+  tags:
+    - Battery Voltage
+  summary: Get Battery Voltage
+  description: |
+    Returns the latest recorded basttery voltage of the vehicle.
+  operationId: getBatteryVoltage
+  security:
+    - basicAuth: []
+  responses:
+    "200":
+      description: Success
+      content:
+        application/json:
+          schema:
+            $ref: "#/components/schemas/BatteryVoltage"
+          example:
+            messageId: mdi-1313382935323227381
+            asset: "3516220738006655"
+            recordedAt": "2019-12-04T05:54:51Z"
+            voltage: 12.09
+    "401":
+      $ref: "#/components/responses/Unauthorized"
+    "404":
+      $ref: "#/components/responses/DataNotFound"
diff --git a/spec/paths/asset@{assetId}@batteryVoltage@history.yaml b/spec/paths/asset@{assetId}@batteryVoltage@history.yaml
new file mode 100644
index 0000000..78ce45b
--- /dev/null
+++ b/spec/paths/asset@{assetId}@batteryVoltage@history.yaml
@@ -0,0 +1,34 @@
+parameters:
+  - $ref: "#/components/parameters/assetId"
+  - $ref: "#/components/parameters/fromDate"
+  - $ref: "#/components/parameters/toDate"
+
+get:
+  tags:
+    - Battery Voltage
+  summary: Get Battery Voltage history
+  description: |
+    Returns an array of basttery voltage records for the car's battery.
+  operationId: getBatteryVoltageHistory
+  security:
+    - basicAuth: []
+  responses:
+    "200":
+      description: Success
+      content:
+        application/json:
+          schema:
+            $ref: "#/components/schemas/BatteryVoltageArray"
+          example:
+            - messageId: mdi-1313382935323227381
+              asset: "3516220738006655"
+              recordedAt": "2019-12-04T05:54:51Z"
+              voltage: 12.09
+            - messageId: mdi-1313382935323227352
+              asset: "3516220738006655"
+              recordedAt": "2019-12-04T06:54:51Z"
+              voltage: 11.491
+    "401":
+      $ref: "#/components/responses/Unauthorized"
+    "404":
+      $ref: "#/components/responses/DataNotFound"
diff --git a/spec/paths/asset@{assetId}@combined-mileage.yaml b/spec/paths/asset@{assetId}@combined-mileage.yaml
new file mode 100644
index 0000000..66524ff
--- /dev/null
+++ b/spec/paths/asset@{assetId}@combined-mileage.yaml
@@ -0,0 +1,35 @@
+parameters:
+  - $ref: "#/components/parameters/assetId"
+
+get:
+  tags:
+    - Combined Mileage
+  summary: Get combined mileage
+  description: |
+    Returns the latest recorded mileage information for a given IMEI.
+    This endpoint provides both the mileage reported by the vehicle and the mileage calculated by the onboard autoSense device GPS.
+  operationId: getCombinedMileage
+  security:
+    - basicAuth: []
+  responses:
+    "200":
+      description: Success
+      content:
+        application/json:
+          schema:
+            $ref: "#/components/schemas/CombinedMileage"
+          example:
+            GPSMileage:
+              messageId: mdi-1313382935323227381
+              asset: "3516220738006655"
+              recordedAt": "2019-12-04T05:54:51Z"
+              mileage: 12500
+            mileage:
+              messageId: mdi-1313382935323227381
+              asset: "3516220738006655"
+              recordedAt": "2019-12-04T05:54:51Z"
+              mileage: 12500
+    "401":
+      $ref: "#/components/responses/Unauthorized"
+    "404":
+      $ref: "#/components/responses/DataNotFound"
diff --git a/spec/paths/asset@{assetId}@dtc.yaml b/spec/paths/asset@{assetId}@dtc.yaml
new file mode 100644
index 0000000..e01f2a3
--- /dev/null
+++ b/spec/paths/asset@{assetId}@dtc.yaml
@@ -0,0 +1,28 @@
+parameters:
+  - $ref: "#/components/parameters/assetId"
+
+get:
+  tags:
+    - DTC
+  summary: Get DTC codes
+  description: |
+    Returns the latest recorded Diagnostics Trouble Codes (DTC) from the vehicle's onboard diagnostics system in a stringified JSON format.
+  operationId: getDtc
+  security:
+    - basicAuth: []
+  responses:
+    "200":
+      description: Success
+      content:
+        application/json:
+          schema:
+            $ref: "#/components/schemas/DTC"
+          example:
+            messageId: mdi-1313382935323227381
+            asset: "3516220738006655"
+            recordedAt": "2019-12-04T05:54:51Z"
+            rawData: "[{\"mode\":3,\"ecu\":\"7E8\",\"dtc\":\"U11F5\"}]"
+    "401":
+      $ref: "#/components/responses/Unauthorized"
+    "404":
+      $ref: "#/components/responses/DataNotFound"
diff --git a/spec/paths/asset@{assetId}@dtc@history.yaml b/spec/paths/asset@{assetId}@dtc@history.yaml
new file mode 100644
index 0000000..ae5b651
--- /dev/null
+++ b/spec/paths/asset@{assetId}@dtc@history.yaml
@@ -0,0 +1,34 @@
+parameters:
+  - $ref: "#/components/parameters/assetId"
+  - $ref: "#/components/parameters/fromDate"
+  - $ref: "#/components/parameters/toDate"
+
+get:
+  tags:
+    - DTC
+  summary: Get DTC codes history
+  description: |
+    Returns an array of the recorded Diagnostics Trouble Codes (DTC) from the vehicle's onboard diagnostics system in a stringified JSON format.
+  operationId: getDtc
+  security:
+    - basicAuth: []
+  responses:
+    "200":
+      description: Success
+      content:
+        application/json:
+          schema:
+            $ref: "#/components/schemas/DTCArray"
+          example:
+            - messageId: mdi-1313382935323227381
+              asset: "3516220738006655"
+              recordedAt": "2019-12-04T05:54:51Z"
+              rawData: "[{\"mode\":7,\"ecu\":\"7E8\",\"dtc\":\"U11F5\"}]"
+            - messageId: mdi-1313382935323227352
+              asset: "3516220738006655"
+              recordedAt": "2019-12-04T06:54:51Z"
+              rawData: "[{\"mode\":7,\"ecu\":\"7E8\",\"dtc\":\"U11F5\"}]"
+    "401":
+      $ref: "#/components/responses/Unauthorized"
+    "404":
+      $ref: "#/components/responses/DataNotFound"
diff --git a/spec/paths/asset@{assetId}@fuel@history?fromDate=date1&toDate=date2.yaml b/spec/paths/asset@{assetId}@fuel@history.yaml
similarity index 100%
rename from spec/paths/asset@{assetId}@fuel@history?fromDate=date1&toDate=date2.yaml
rename to spec/paths/asset@{assetId}@fuel@history.yaml
diff --git a/spec/paths/asset@{assetId}@mil.yaml b/spec/paths/asset@{assetId}@mil.yaml
new file mode 100644
index 0000000..a735ab1
--- /dev/null
+++ b/spec/paths/asset@{assetId}@mil.yaml
@@ -0,0 +1,28 @@
+parameters:
+  - $ref: "#/components/parameters/assetId"
+
+get:
+  tags:
+    - MIL
+  summary: Get MIL codes
+  description: |
+    Returns the latest recorded Malfunction Indicator Light (MIL) codes from the vehicle's onboard diagnostics system in a stringified JSON format.
+  operationId: getMil
+  security:
+    - basicAuth: []
+  responses:
+    "200":
+      description: Success
+      content:
+        application/json:
+          schema:
+            $ref: "#/components/schemas/DTC"
+          example:
+            messageId: mdi-1313382935323227381
+            asset: "3516220738006655"
+            recordedAt": "2019-12-04T05:54:51Z"
+            rawData: "[{\"mode\":3,\"ecu\":\"7E8\",\"dtc\":\"U11F5\"}]"
+    "401":
+      $ref: "#/components/responses/Unauthorized"
+    "404":
+      $ref: "#/components/responses/DataNotFound"
diff --git a/spec/paths/asset@{assetId}@mil@history.yaml b/spec/paths/asset@{assetId}@mil@history.yaml
new file mode 100644
index 0000000..7bf2946
--- /dev/null
+++ b/spec/paths/asset@{assetId}@mil@history.yaml
@@ -0,0 +1,34 @@
+parameters:
+  - $ref: "#/components/parameters/assetId"
+  - $ref: "#/components/parameters/fromDate"
+  - $ref: "#/components/parameters/toDate"
+
+get:
+  tags:
+    - MIL
+  summary: Get MIL codes history
+  description: |
+    Returns an array of the recorded Malfunction Indicator Light (MIL) codes from the vehicle's onboard diagnostics system in a stringified JSON format.
+  operationId: getMilHistory
+  security:
+    - basicAuth: []
+  responses:
+    "200":
+      description: Success
+      content:
+        application/json:
+          schema:
+            $ref: "#/components/schemas/DTCArray"
+          example:
+            - messageId: mdi-1313382935323227381
+              asset: "3516220738006655"
+              recordedAt": "2019-12-04T05:54:51Z"
+              <??????>: "[{\"mode\":7,\"ecu\":\"7E8\",\"dtc\":\"U11F5\"}]"
+            - messageId: mdi-1313382935323227352
+              asset: "3516220738006655"
+              recordedAt": "2019-12-04T06:54:51Z"
+              <??????>: "[{\"mode\":7,\"ecu\":\"7E8\",\"dtc\":\"U11F5\"}]"
+    "401":
+      $ref: "#/components/responses/Unauthorized"
+    "404":
+      $ref: "#/components/responses/DataNotFound"
diff --git a/spec/paths/asset@{assetId}@mileage.yaml b/spec/paths/asset@{assetId}@mileage.yaml
index 518e440..0a5ff86 100644
--- a/spec/paths/asset@{assetId}@mileage.yaml
+++ b/spec/paths/asset@{assetId}@mileage.yaml
@@ -7,6 +7,7 @@ get:
   summary: Get mileage
   description: |
     Returns the latest recorded mileage information for a given IMEI.
+    This endpoint refers to the mileage reported by the vehicle.
   operationId: getMileage
   security:
     - basicAuth: []
diff --git a/spec/paths/asset@{assetId}@mileage@history?fromDate=date1&toDate=date2.yaml b/spec/paths/asset@{assetId}@mileage@history.yaml
similarity index 100%
rename from spec/paths/asset@{assetId}@mileage@history?fromDate=date1&toDate=date2.yaml
rename to spec/paths/asset@{assetId}@mileage@history.yaml
diff --git a/spec/paths/asset@{assetId}@obdmileage.yaml b/spec/paths/asset@{assetId}@obdmileage.yaml
new file mode 100644
index 0000000..3d31b43
--- /dev/null
+++ b/spec/paths/asset@{assetId}@obdmileage.yaml
@@ -0,0 +1,29 @@
+parameters:
+  - $ref: "#/components/parameters/assetId"
+
+get:
+  tags:
+    - GPS Mileage
+  summary: Get GPS mileage
+  description: |
+    Returns the latest recorded GPS mileage information for a given IMEI.
+    This endpoint refers to the mileage calculated by the device's GPS.
+  operationId: getGPSMileage
+  security:
+    - basicAuth: []
+  responses:
+    "200":
+      description: Success
+      content:
+        application/json:
+          schema:
+            $ref: "#/components/schemas/Mileage"
+          example:
+            messageId: mdi-1313382935323227381
+            asset: "3516220738006655"
+            recordedAt": "2019-12-04T05:54:51Z"
+            mileage: 11560
+    "401":
+      $ref: "#/components/responses/Unauthorized"
+    "404":
+      $ref: "#/components/responses/DataNotFound"
diff --git a/spec/paths/asset@{assetId}@obdmileage@history.yaml b/spec/paths/asset@{assetId}@obdmileage@history.yaml
new file mode 100644
index 0000000..96e8973
--- /dev/null
+++ b/spec/paths/asset@{assetId}@obdmileage@history.yaml
@@ -0,0 +1,35 @@
+parameters:
+  - $ref: "#/components/parameters/assetId"
+  - $ref: "#/components/parameters/fromDate"
+  - $ref: "#/components/parameters/toDate"
+
+get:
+  tags:
+    - GPS Mileage
+  summary: Get GPS mileage history
+  description: |
+    Returns an array of GPS mileage messages for a given IMEI within the provided date range.
+    This endpoint refers to the mileage calculated by the device's GPS.
+  operationId: getMileageHistory
+  security:
+    - basicAuth: []
+  responses:
+    "200":
+      description: Success
+      content:
+        application/json:
+          schema:
+            $ref: "#/components/schemas/MileageArray"
+          example:
+            - messageId: mdi-1313382935323227381
+              asset: "3516220738006655"
+              recordedAt": "2019-12-04T05:54:51Z"
+              mileage: 12500
+            - messageId: mdi-1313382935323227382
+              asset: "3516220738006655"
+              recordedAt": "2019-12-04T05:55:51Z"
+              mileage: 12505
+    "401":
+      $ref: "#/components/responses/Unauthorized"
+    "404":
+      $ref: "#/components/responses/DataNotFound"
diff --git a/spec/paths/asset@{assetId}@plugUnplug@history?fromDate=date1&toDate=date2.yaml b/spec/paths/asset@{assetId}@plugUnplug@history.yaml
similarity index 100%
rename from spec/paths/asset@{assetId}@plugUnplug@history?fromDate=date1&toDate=date2.yaml
rename to spec/paths/asset@{assetId}@plugUnplug@history.yaml
diff --git a/spec/paths/asset@{assetId}@vin.yaml b/spec/paths/asset@{assetId}@vin.yaml
new file mode 100644
index 0000000..c09e290
--- /dev/null
+++ b/spec/paths/asset@{assetId}@vin.yaml
@@ -0,0 +1,29 @@
+parameters:
+  - $ref: "#/components/parameters/assetId"
+
+get:
+  tags:
+    - VIN
+  summary: Get VIN
+  description: |
+    Returns the latest recorded Vehicle Identification Number (VIN) for a given IMEI.
+  operationId: getVin
+  security:
+    - basicAuth: []
+  responses:
+    "200":
+      description: Success
+      content:
+        application/json:
+          schema:
+            $ref: "#/components/schemas/Vin"
+          example:
+            messageId: mdi-1313382935323227381
+            asset: "3516220738006655"
+            recordedAt": "2019-12-04T05:54:51Z"
+            vin: WP0ZZZ99ZTS392124
+    "401":
+      $ref: "#/components/responses/Unauthorized"
+    "404":
+      $ref: "#/components/responses/DataNotFound"
+
diff --git a/spec/paths/asset@{assetId}@vin@history.yaml b/spec/paths/asset@{assetId}@vin@history.yaml
new file mode 100644
index 0000000..e85026c
--- /dev/null
+++ b/spec/paths/asset@{assetId}@vin@history.yaml
@@ -0,0 +1,34 @@
+parameters:
+  - $ref: "#/components/parameters/assetId"
+  - $ref: "#/components/parameters/fromDate"
+  - $ref: "#/components/parameters/toDate"
+
+get:
+  tags:
+    - VIN
+  summary: Get VIN history
+  description: |
+    Returns an array of Vehicle Identification Number (VIN) for a given IMEI within the provided date range.
+  operationId: getVINHistory
+  security:
+    - basicAuth: []
+  responses:
+    "200":
+      description: Success
+      content:
+        application/json:
+          schema:
+            $ref: "#/components/schemas/VinArray"
+          example:
+            - messageId: mdi-1313382935323227381
+              asset: "3516220738006655"
+              recordedAt": "2019-12-04T05:54:51Z"
+              vin: WP0ZZZ99ZTS392124
+            - messageId: mdi-1313382935323227382
+              asset: "3516220738006655"
+              recordedAt": "2019-12-04T05:55:51Z"
+              vin: WP0ZZZ99ZTS392124
+    "401":
+      $ref: "#/components/responses/Unauthorized"
+    "404":
+      $ref: "#/components/responses/DataNotFound"