From 6bcd445a7098fe637279bde689d558a05add0263 Mon Sep 17 00:00:00 2001
From: Cameron Pfiffer <cameron@pfiffer.org>
Date: Mon, 10 Aug 2026 15:53:48 -0700
Subject: [PATCH] Verify X subscription creates by readback.
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Treat the provider create response as an acknowledgment when it omits a subscription record, then require one exact live match before continuing the mutation plan.

👾 Generated with [Letta Code](https://letta.com)

Co-Authored-By: Letta Code <noreply@letta.com>
---
 src/connectors/x-client.ts | 19 +++++++++++++++++--
 test/x-client.test.ts      |  3 ++-
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/src/connectors/x-client.ts b/src/connectors/x-client.ts
index 5670358..79e53ce 100644
--- a/src/connectors/x-client.ts
+++ b/src/connectors/x-client.ts
@@ -130,8 +130,23 @@ export class XApiClient {
       tag: boundedTag(subscription.tag),
       webhook_id: xNumericIdSchema.parse(subscription.webhookId),
     }, signal);
-    const data = z.object({ data: z.union([subscriptionSchema, z.array(subscriptionSchema).min(1)]) }).passthrough().parse(response).data;
-    return normalizeSubscription(Array.isArray(data) ? data[0]! : data);
+    const parsed = z.object({
+      data: z.union([subscriptionSchema, z.array(subscriptionSchema).min(1)]),
+    }).passthrough().safeParse(response);
+    if (parsed.success) {
+      const data = parsed.data.data;
+      return normalizeSubscription(Array.isArray(data) ? data[0]! : data);
+    }
+    const matches = (await this.listSubscriptions(signal)).filter((candidate) => (
+      candidate.eventType === subscription.eventType
+      && candidate.userId === subscription.userId
+      && candidate.tag === subscription.tag
+      && candidate.webhookId === subscription.webhookId
+    ));
+    if (matches.length !== 1) {
+      throw new Error("X subscription creation response was not a subscription and exact readback did not converge");
+    }
+    return matches[0]!;
   }
 
   async updateSubscription(
diff --git a/test/x-client.test.ts b/test/x-client.test.ts
index fdfac98..c4e572a 100644
--- a/test/x-client.test.ts
+++ b/test/x-client.test.ts
@@ -68,6 +68,7 @@ describe("X management client", () => {
       "GET /2/users/by/username/karpathy",
       "POST /2/activity/subscriptions",
       "GET /2/activity/subscriptions",
+      "GET /2/activity/subscriptions",
       `PUT /2/activity/subscriptions/${subscription.id}`,
       "POST /2/webhooks/replay",
       `DELETE /2/activity/subscriptions/${subscription.id}`,
@@ -233,7 +234,7 @@ async function xApiFixture() {
         updated_at: "2026-08-10T10:00:00.000Z",
       };
       subscriptions.push(record);
-      send(response, 200, { data: record });
+      send(response, 200, { data: { accepted: true } });
       return;
     }
     const subscriptionMatch = /^\/2\/activity\/subscriptions\/([0-9]+)$/.exec(url.pathname);
-- 
2.51.2