docs: add isReplay to context docs and replaying page

Co-Authored-By: nick <55853254+nicktrn@users.noreply.github.com>

Author: devin-ai-integration[bot]

docs/context.mdx

@@ -81,6 +81,9 @@ export const parentTask = task({
     <ResponseField name="isTest" type="boolean">
       Whether this is a [test run](/run-tests).
     </ResponseField>
+    <ResponseField name="isReplay" type="boolean">
+      Whether this run is a [replay](/replaying) of a previous run.
+    </ResponseField>
     <ResponseField name="createdAt" type="date">
       The creation time of the task run.
     </ResponseField>

docs/replaying.mdx

@@ -30,6 +30,21 @@ description: "A replay is a copy of a run with the same payload but against the
   </Tab>
 </Tabs>
 
+### Detecting replays in your task
+
+You can check if a run is a replay using the [context](/context) object:
+
+```ts
+export const myTask = task({
+  id: "my-task",
+  run: async (payload, { ctx }) => {
+    if (ctx.run.isReplay) {
+      // This run is a replay of a previous run
+    }
+  },
+});
+```
+
 ### Replaying using the SDK
 
 You can replay a run using the SDK: