diff --git a/apps/server/src/mcp/toolkits/core.test.ts b/apps/server/src/mcp/toolkits/core.test.ts
index 0e9b5cb557d41..81614e5eb4274 100644
--- a/apps/server/src/mcp/toolkits/core.test.ts
+++ b/apps/server/src/mcp/toolkits/core.test.ts
@@ -1126,6 +1126,54 @@ it.effect.each([
   ),
 );
 
+it.effect("run_scheduled_task_now reports why a started run failed to dispatch", () =>
+  Effect.gen(function* () {
+    const server = yield* McpServer.McpServer;
+    const result = yield* server
+      .callTool({ name: "run_scheduled_task_now", arguments: { taskId: "task-full-access" } })
+      .pipe(
+        Effect.provideService(
+          McpInvocationContext.McpInvocationContext,
+          clientScope("full-access"),
+        ),
+        Effect.provideService(McpSchema.McpServerClient, client),
+      );
+    expect(result.isError).toBe(false);
+    expect(result.structuredContent).toMatchObject({
+      threadId: null,
+      lastRunStatus: "failed",
+      lastRunError: "the provider is disabled",
+    });
+  }).pipe(
+    Effect.provide(
+      McpHttpServer.layerThreadToolkit.pipe(
+        Layer.provideMerge(McpHttpServer.layerInProcessMcpServer),
+        Layer.provide(NodeCrypto.layer),
+        Layer.provide(Layer.mock(ThreadManagement.ThreadManagementService)({})),
+        Layer.provide(Layer.mock(ThreadSearch.ThreadSearch)({})),
+        Layer.provide(Layer.mock(PeerForwarding.PeerForwarding)({})),
+        Layer.provide(Layer.mock(PeerLinkRequests.PeerLinkRequests)({})),
+        Layer.provide(Layer.mock(PeerLinks.PeerLinks)({})),
+        Layer.provide(
+          Layer.mock(ScheduledTaskService.ScheduledTaskService)({
+            list: () =>
+              Effect.succeed({ tasks: [scheduledTask("task-full-access", "full-access")] }),
+            runNow: () =>
+              Effect.succeed({
+                threadId: null,
+                task: {
+                  ...(scheduledTask("task-full-access", "full-access") as object),
+                  lastRunStatus: "failed" as const,
+                  lastRunError: "the provider is disabled",
+                },
+              } as never),
+          }),
+        ),
+      ),
+    ),
+  ),
+);
+
 function scheduledTask(id: string, runtimeMode: "auto" | "full-access"): never {
   return {
     id,
diff --git a/apps/server/src/mcp/toolkits/thread/handlers.ts b/apps/server/src/mcp/toolkits/thread/handlers.ts
index 03b796c6da892..972174638e10f 100644
--- a/apps/server/src/mcp/toolkits/thread/handlers.ts
+++ b/apps/server/src/mcp/toolkits/thread/handlers.ts
@@ -134,6 +134,7 @@ export const layer = McpToolAccess.toLayer(ThreadToolkit, {
               link: McpInvocationContext.threadLinkFor(scope, threadId),
             }),
         lastRunStatus: task.lastRunStatus,
+        lastRunError: task.lastRunError,
         runCount: task.runCount,
         nextRunAt: task.nextRunAt,
       };
diff --git a/apps/server/src/mcp/toolkits/thread/tools.ts b/apps/server/src/mcp/toolkits/thread/tools.ts
index bea03c83c8465..d6c9a34565ddb 100644
--- a/apps/server/src/mcp/toolkits/thread/tools.ts
+++ b/apps/server/src/mcp/toolkits/thread/tools.ts
@@ -232,6 +232,7 @@ const ScheduledTaskRunTool = Tool.make("run_scheduled_task_now", {
     threadId: ScheduledTask.fields.threadId,
     link: Schema.optional(Schema.String),
     lastRunStatus: ScheduledTask.fields.lastRunStatus,
+    lastRunError: ScheduledTask.fields.lastRunError,
     runCount: NonNegativeInt,
     nextRunAt: ScheduledTask.fields.nextRunAt,
   }),