diff --git a/docs/controllers/SessionController.yaml b/docs/controllers/SessionController.yaml
new file mode 100644
index 000000000..70cab2843
--- /dev/null
+++ b/docs/controllers/SessionController.yaml
@@ -0,0 +1,55 @@
+paths:
+  /api/session/{id}/sync:
+    post:
+      operationId: syncOpenSession
+      summary: Sync an open session.
+      description: Sync an open session.
+      tags:
+        - Session
+      parameters:
+        - name: id
+          in: path
+          description: The ID of the session.
+          required: true
+          schema:
+            $ref: '../objects/entities/PlaybackSession.yaml#/components/schemas/playbackSessionId'
+        - name: currentTime
+          in: query
+          description: The current time of the session.
+          required: true
+          schema:
+              $ref: '../schemas.yaml#/components/schemas/durationSec'
+        - name: timeListened
+          in: query
+          description: The time listened to the session.
+          required: true
+          schema:
+              $ref: '../schemas.yaml#/components/schemas/durationSec'
+        - name: duration
+          in: query
+          description: The duration of the session.
+          required: true
+          schema:
+              $ref: '../schemas.yaml#/components/schemas/durationSec'
+      responses:
+        '200':
+            description: OK
+            content:
+                html/text:
+                  schema:
+                      type: string
+                      example: OK
+        '404':
+            description: No listening session with the provided ID is open, or the session belongs to another user.
+            content:
+                html/text:
+                  schema:
+                      type: string
+                      example: Not Found
+        '500':
+            description: There was an error syncing the session.
+            content:
+                html/text:
+                  schema:
+                      type: string
+                      example: Internal Server Error
diff --git a/docs/openapi.json b/docs/openapi.json
index d72acb3e6..c5edd2706 100644
Binary files a/docs/openapi.json and b/docs/openapi.json differ
diff --git a/docs/root.yaml b/docs/root.yaml
index ff2c6f21f..63462a22c 100644
--- a/docs/root.yaml
+++ b/docs/root.yaml
@@ -91,6 +91,8 @@ paths:
     $ref: './controllers/MeController.yaml#/paths/~1api~1me~1progress~1{libraryItemId}~1{episodeId}'
   /api/me/progress/{mediaId}:
     $ref: './controllers/MeController.yaml#/paths/~1api~1me~1progress~1{mediaId}'
+  /api/session/{id}/sync:
+    $ref: './controllers/SessionController.yaml#/paths/~1api~1session~1{id}~1sync'
 tags:
   - name: Authors
     description: Author endpoints