diff --git a/CHANGELOG.md b/CHANGELOG.md
index b4222fb3337..6f445db8d10 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -19,6 +19,7 @@ Docs: https://docs.openclaw.ai
 - Dreaming/diary: use the host local timezone for diary timestamps when `dreaming.timezone` is unset, so `DREAMS.md` and the UI stop defaulting to UTC. (#65034) Thanks @neo1027144-creator and @vincentkoc.
 - Plugins/memory: restore cached memory capability public artifacts on plugin-registry cache hits so memory-backed artifact surfaces stay visible after warm loads. Thanks @sercada and @vincentkoc.
 - Gateway/cron: preserve requested isolated-agent config across runtime reloads so subagent jobs and heartbeat overrides keep the right workspace and heartbeat settings when the hot-loaded snapshot is stale. Thanks @l0cka and @vincentkoc.
+- Gateway/plugins: always send a non-empty `idempotencyKey` for plugin subagent runs, so dreaming narrative jobs stop failing gateway schema validation. (#65354) Thanks @CodeForgeNet and @vincentkoc.
 - Cron/isolated sessions: persist the right transcript path for each isolated run, including fresh session rollovers, so cron runs stop appending to stale session files. Thanks @samrusani and @vincentkoc.
 - Dreaming/cron: wake managed dreaming jobs immediately instead of waiting for the next heartbeat, so scheduled dreaming runs start when the cron fires. (#65053) Thanks @l0cka and @vincentkoc.
 
diff --git a/src/gateway/server-plugins.test.ts b/src/gateway/server-plugins.test.ts
index 59a0b2a00be..1d047880181 100644
--- a/src/gateway/server-plugins.test.ts
+++ b/src/gateway/server-plugins.test.ts
@@ -556,6 +556,46 @@ describe("loadGatewayPlugins", () => {
     });
   });
 
+  test("forwards caller-supplied idempotencyKey on subagent run", async () => {
+    const serverPlugins = serverPluginsModule;
+    const runtime = await createSubagentRuntime(serverPlugins);
+    serverPlugins.setFallbackGatewayContext(createTestContext("idempotency-forward"));
+
+    await runtime.run({
+      sessionKey: "s-idem-forward",
+      message: "hello",
+      deliver: false,
+      idempotencyKey: "caller-provided-key",
+    });
+
+    expect(getLastDispatchedParams()).toMatchObject({
+      sessionKey: "s-idem-forward",
+      message: "hello",
+      idempotencyKey: "caller-provided-key",
+    });
+  });
+
+  test("generates a non-empty idempotencyKey when the caller omits it", async () => {
+    const serverPlugins = serverPluginsModule;
+    const runtime = await createSubagentRuntime(serverPlugins);
+    serverPlugins.setFallbackGatewayContext(createTestContext("idempotency-generate"));
+
+    await runtime.run({
+      sessionKey: "s-idem-generate",
+      message: "hello",
+      deliver: false,
+    });
+
+    const params = getLastDispatchedParams();
+    expect(params).toBeDefined();
+    // The gateway `agent` schema requires `idempotencyKey: NonEmptyString`, so
+    // the runtime must always send a populated value. A missing field here
+    // would reproduce the memory-core dreaming-narrative regression.
+    const generated = params?.idempotencyKey;
+    expect(typeof generated).toBe("string");
+    expect((generated as string).length).toBeGreaterThan(0);
+  });
+
   test("rejects provider/model overrides for fallback runs without explicit authorization", async () => {
     const serverPlugins = serverPluginsModule;
     const runtime = await createSubagentRuntime(serverPlugins);
diff --git a/src/gateway/server-plugins.ts b/src/gateway/server-plugins.ts
index 7b561f1048f..71b5d4d6af0 100644
--- a/src/gateway/server-plugins.ts
+++ b/src/gateway/server-plugins.ts
@@ -338,7 +338,11 @@ export function createGatewaySubagentRuntime(): PluginRuntime["subagent"] {
           ...(allowOverride && params.model && { model: params.model }),
           ...(params.extraSystemPrompt && { extraSystemPrompt: params.extraSystemPrompt }),
           ...(params.lane && { lane: params.lane }),
-          ...(params.idempotencyKey && { idempotencyKey: params.idempotencyKey }),
+          // The gateway `agent` schema requires `idempotencyKey: NonEmptyString`,
+          // so fall back to a generated UUID when the caller omits it. Without
+          // this, plugin subagent runs (for example memory-core dreaming
+          // narrative) silently fail schema validation at the gateway.
+          idempotencyKey: params.idempotencyKey || randomUUID(),
         },
         {
           allowSyntheticModelOverride,