diff --git a/ui/src/context/LiveUpdatesProvider.test.ts b/ui/src/context/LiveUpdatesProvider.test.ts
index 3a66cec4..c24faf70 100644
--- a/ui/src/context/LiveUpdatesProvider.test.ts
+++ b/ui/src/context/LiveUpdatesProvider.test.ts
@@ -117,3 +117,77 @@ describe("LiveUpdatesProvider visible issue toast suppression", () => {
     ).toBe(true);
   });
 });
+
+describe("LiveUpdatesProvider run lifecycle toasts", () => {
+  it("does not build start or success toasts for agent runs", () => {
+    const queryClient = {
+      getQueryData: () => [],
+    };
+
+    expect(
+      __liveUpdatesTestUtils.buildAgentStatusToast(
+        {
+          agentId: "agent-1",
+          status: "running",
+        },
+        () => "CodexCoder",
+        queryClient as never,
+        "company-1",
+      ),
+    ).toBeNull();
+
+    expect(
+      __liveUpdatesTestUtils.buildRunStatusToast(
+        {
+          runId: "run-1",
+          agentId: "agent-1",
+          status: "succeeded",
+        },
+        () => "CodexCoder",
+      ),
+    ).toBeNull();
+  });
+
+  it("still builds failure toasts for agent errors and failed runs", () => {
+    const queryClient = {
+      getQueryData: () => [
+        {
+          id: "agent-1",
+          title: "Software Engineer",
+        },
+      ],
+    };
+
+    expect(
+      __liveUpdatesTestUtils.buildAgentStatusToast(
+        {
+          agentId: "agent-1",
+          status: "error",
+        },
+        () => "CodexCoder",
+        queryClient as never,
+        "company-1",
+      ),
+    ).toMatchObject({
+      title: "CodexCoder errored",
+      body: "Software Engineer",
+      tone: "error",
+    });
+
+    expect(
+      __liveUpdatesTestUtils.buildRunStatusToast(
+        {
+          runId: "run-1",
+          agentId: "agent-1",
+          status: "failed",
+          error: "boom",
+        },
+        () => "CodexCoder",
+      ),
+    ).toMatchObject({
+      title: "CodexCoder run failed",
+      body: "boom",
+      tone: "error",
+    });
+  });
+});
diff --git a/ui/src/context/LiveUpdatesProvider.tsx b/ui/src/context/LiveUpdatesProvider.tsx
index ec593b3b..20132721 100644
--- a/ui/src/context/LiveUpdatesProvider.tsx
+++ b/ui/src/context/LiveUpdatesProvider.tsx
@@ -244,8 +244,8 @@ function shouldSuppressAgentStatusToastForVisibleIssue(
 }
 
 const ISSUE_TOAST_ACTIONS = new Set(["issue.created", "issue.updated", "issue.comment_added"]);
-const AGENT_TOAST_STATUSES = new Set(["running", "error"]);
-const TERMINAL_RUN_STATUSES = new Set(["succeeded", "failed", "timed_out", "cancelled"]);
+const AGENT_TOAST_STATUSES = new Set(["error"]);
+const RUN_TOAST_STATUSES = new Set(["failed", "timed_out", "cancelled"]);
 
 function describeIssueUpdate(details: Record<string, unknown> | null): string | null {
   if (!details) return null;
@@ -416,7 +416,7 @@ function buildRunStatusToast(
   const runId = readString(payload.runId);
   const agentId = readString(payload.agentId);
   const status = readString(payload.status);
-  if (!runId || !agentId || !status || !TERMINAL_RUN_STATUSES.has(status)) return null;
+  if (!runId || !agentId || !status || !RUN_TOAST_STATUSES.has(status)) return null;
 
   const error = readString(payload.error);
   const triggerDetail = readString(payload.triggerDetail);
@@ -653,6 +653,8 @@ function handleLiveEvent(
 }
 
 export const __liveUpdatesTestUtils = {
+  buildAgentStatusToast,
+  buildRunStatusToast,
   invalidateActivityQueries,
   shouldSuppressActivityToastForVisibleIssue,
   shouldSuppressRunStatusToastForVisibleIssue,