diff --git a/extensions/teams/cleanup.ts b/extensions/teams/cleanup.ts
index 61b2f34..b2040f4 100644
--- a/extensions/teams/cleanup.ts
+++ b/extensions/teams/cleanup.ts
@@ -79,13 +79,15 @@ export async function gcStaleTeamDirs(opts: {
 	maxAgeMs: number;
 	repoCwd?: string;
 	dryRun?: boolean;
+	/** Team IDs to skip (e.g. the current session's team). */
+	excludeTeamIds?: ReadonlySet<string>;
 }): Promise<{
 	scanned: number;
 	removed: string[];
 	skipped: Array<{ teamId: string; reason: string }>;
 	warnings: string[];
 }> {
-	const { teamsRootDir, maxAgeMs, repoCwd, dryRun } = opts;
+	const { teamsRootDir, maxAgeMs, repoCwd, dryRun, excludeTeamIds } = opts;
 	const teamsRootAbs = path.resolve(teamsRootDir);
 	const removed: string[] = [];
 	const skipped: Array<{ teamId: string; reason: string }> = [];
@@ -103,6 +105,10 @@ export async function gcStaleTeamDirs(opts: {
 	const now = Date.now();
 
 	for (const teamId of teamEntries) {
+		if (excludeTeamIds?.has(teamId)) {
+			skipped.push({ teamId, reason: "excluded" });
+			continue;
+		}
 		const teamDir = path.join(teamsRootAbs, teamId);
 		let stat: fs.Stats;
 		try {
diff --git a/extensions/teams/leader.ts b/extensions/teams/leader.ts
index e675712..9834fe3 100644
--- a/extensions/teams/leader.ts
+++ b/extensions/teams/leader.ts
@@ -9,8 +9,9 @@ import { TEAM_MAILBOX_NS, taskAssignmentPayload } from "./protocol.js";
 import { createTask, listTasks, unassignTasksForAgent, updateTask, type TeamTask } from "./task-store.js";
 import { TeammateRpc } from "./teammate-rpc.js";
 import { ensureTeamConfig, loadTeamConfig, setMemberStatus, upsertMember, type TeamConfig } from "./team-config.js";
-import { getTeamDir } from "./paths.js";
-import { heartbeatTeamAttachClaim, releaseTeamAttachClaim } from "./team-attach-claim.js";
+import { getTeamDir, getTeamsRootDir } from "./paths.js";
+import { assessAttachClaimFreshness, heartbeatTeamAttachClaim, readTeamAttachClaim, releaseTeamAttachClaim } from "./team-attach-claim.js";
+import { cleanupTeamDir, gcStaleTeamDirs } from "./cleanup.js";
 import { ensureWorktreeCwd, cleanupWorktrees } from "./worktree.js";
 import { ActivityTracker, TranscriptTracker } from "./activity-tracker.js";
 import { openInteractiveWidget } from "./teams-panel.js";
@@ -106,6 +107,29 @@ async function createSessionForTeammate(
 	}
 }
 
+/** Check if a team dir has any task files across all task-list namespaces. */
+async function teamDirHasAnyTasks(teamDir: string): Promise<boolean> {
+	const tasksDir = path.join(teamDir, "tasks");
+	let taskListDirs: string[];
+	try {
+		taskListDirs = await fs.promises.readdir(tasksDir);
+	} catch {
+		return false;
+	}
+	for (const listDir of taskListDirs) {
+		const listPath = path.join(tasksDir, listDir);
+		try {
+			const stat = await fs.promises.stat(listPath);
+			if (!stat.isDirectory()) continue;
+			const files = await fs.promises.readdir(listPath);
+			if (files.some((f) => f.endsWith(".json") && !f.startsWith("."))) return true;
+		} catch {
+			continue;
+		}
+	}
+	return false;
+}
+
 // Message parsers are shared with the worker implementation.
 export function runLeader(pi: ExtensionAPI): void {
 	const teammates = new Map<string, TeammateRpc>();
@@ -701,6 +725,15 @@ export function runLeader(pi: ExtensionAPI): void {
 			style,
 		});
 
+		// Startup GC: silently remove stale team directories from previous sessions (24h age floor).
+		void gcStaleTeamDirs({
+			teamsRootDir: getTeamsRootDir(),
+			maxAgeMs: 24 * 60 * 60 * 1000,
+			excludeTeamIds: new Set([currentTeamId]),
+		}).catch(() => {
+			// Best-effort; never block the session.
+		});
+
 		await refreshTasks();
 		renderWidget();
 
@@ -804,6 +837,7 @@ export function runLeader(pi: ExtensionAPI): void {
 		if (!currentCtx) return;
 		await releaseActiveAttachClaim(currentCtx);
 		stopLoops();
+		const hadTeammates = teammates.size > 0;
 		const strings = getTeamsStrings(style);
 		await stopAllTeammates(currentCtx, `The ${strings.teamNoun} is over`);
 
@@ -817,6 +851,30 @@ export function runLeader(pi: ExtensionAPI): void {
 			} catch {
 				// Best-effort — don't block shutdown.
 			}
+
+			// Exit cleanup: delete own team directory if it's empty.
+			// Conservative: only if no RPC teammates were active, no online workers in
+			// config (manual/tmux), no tasks in ANY namespace, and no fresh attach claim.
+			// (Dirs with completed tasks are left for the 24h startup GC — intentionally
+			// asymmetric for safety.)
+			if (!hadTeammates) {
+				try {
+					const claim = await readTeamAttachClaim(teamDir);
+					const claimIsLive = claim !== null && !assessAttachClaimFreshness(claim).isStale;
+					if (claimIsLive) {
+						// Another session is using this team — don't delete.
+					} else {
+						// Also check config for online non-lead members (manual/tmux workers).
+						const cfg = await loadTeamConfig(teamDir);
+						const hasOnlineWorkers = cfg?.members.some((m) => m.role !== "lead" && m.status === "online") ?? false;
+						if (!hasOnlineWorkers && !(await teamDirHasAnyTasks(teamDir))) {
+							await cleanupTeamDir(getTeamsRootDir(), teamDir);
+						}
+					}
+				} catch {
+					// Best-effort; never block shutdown.
+				}
+			}
 		}
 	});