diff --git a/http-client/index.ts b/http-client/index.ts
index e663d19ba..64f2fea6b 100644
--- a/http-client/index.ts
+++ b/http-client/index.ts
@@ -35,6 +35,7 @@ import type { Issue, IssueState } from "./lib/repo/issue.js";
 import type {
   LifecycleState,
   Merge,
+  MergeTarget,
   Patch,
   PatchState,
   Review,
@@ -88,6 +89,7 @@ export type {
   LifecycleState,
   Location,
   Merge,
+  MergeTarget,
   Patch,
   PatchState,
   PeerRefs,
diff --git a/http-client/lib/repo/patch.ts b/http-client/lib/repo/patch.ts
index caafb7fe6..534e95067 100644
--- a/http-client/lib/repo/patch.ts
+++ b/http-client/lib/repo/patch.ts
@@ -34,6 +34,13 @@ const patchStateSchema = union([
   }),
 ]);
 
+export type MergeTarget = z.infer<typeof mergeTargetSchema>;
+
+const mergeTargetSchema = union([
+  literal("delegates"),
+  object({ branch: string() }),
+]);
+
 export type Merge = z.infer<typeof mergeSchema>;
 
 const mergeSchema = object({
@@ -89,7 +96,7 @@ export const patchSchema = object({
   author: authorSchema,
   title: string(),
   state: patchStateSchema,
-  target: string(),
+  target: mergeTargetSchema,
   labels: array(string()),
   merges: array(mergeSchema),
   assignees: array(authorSchema),