diff --git a/packages/daemon/src/daemon.test.ts b/packages/daemon/src/daemon.test.ts
index 384d9687b..8519bcaf7 100644
--- a/packages/daemon/src/daemon.test.ts
+++ b/packages/daemon/src/daemon.test.ts
@@ -417,7 +417,110 @@ describe('Daemon', () => {
   });
 });
 
-// ---------- CLI integration ----------
+// ---------- Health heartbeat ----------
+
+describe('Health heartbeat', () => {
+  it('logs health entry with expected fields after interval tick', async () => {
+    const dir = tmpDir();
+    cleanupDirs.push(dir);
+    const logPath = join(dir, 'health.log');
+
+    const config: DaemonConfig = {
+      discord: undefined,
+      projects: { scan_roots: [] },
+      log: { file: logPath, level: 'info', max_size_mb: 50 },
+    };
+
+    const logger = new Logger({ filePath: logPath, level: 'info' });
+    // Use 50ms interval for fast test
+    const daemon = new Daemon(config, logger, 50);
+
+    await daemon.start();
+
+    // Wait for at least one health tick
+    await new Promise((r) => setTimeout(r, 120));
+
+    const origExit = process.exit;
+    // @ts-expect-error — overriding process.exit for test
+    process.exit = () => {};
+    try {
+      await daemon.shutdown();
+    } finally {
+      process.exit = origExit;
+    }
+
+    const content = readFileSync(logPath, 'utf-8');
+    const lines = content.trim().split('\n');
+    const healthLines = lines.filter((l) => {
+      const e: LogEntry = JSON.parse(l);
+      return e.msg === 'health';
+    });
+
+    assert.ok(healthLines.length >= 1, 'should have at least one health log entry');
+
+    const entry: LogEntry = JSON.parse(healthLines[0]!);
+    assert.equal(entry.msg, 'health');
+    assert.equal(typeof entry.data?.uptime_s, 'number');
+    assert.equal(typeof entry.data?.active_sessions, 'number');
+    assert.equal(typeof entry.data?.discord_connected, 'boolean');
+    assert.equal(typeof entry.data?.memory_rss_mb, 'number');
+    assert.equal(entry.data?.discord_connected, false); // no discord configured
+    assert.equal(entry.data?.active_sessions, 0); // no sessions
+  });
+
+  it('health timer is cleared on shutdown — no lingering intervals', async () => {
+    const dir = tmpDir();
+    cleanupDirs.push(dir);
+    const logPath = join(dir, 'health-cleanup.log');
+
+    const config: DaemonConfig = {
+      discord: undefined,
+      projects: { scan_roots: [] },
+      log: { file: logPath, level: 'info', max_size_mb: 50 },
+    };
+
+    const logger = new Logger({ filePath: logPath, level: 'info' });
+    // Use 50ms interval
+    const daemon = new Daemon(config, logger, 50);
+
+    await daemon.start();
+
+    // Wait for one tick
+    await new Promise((r) => setTimeout(r, 80));
+
+    const origExit = process.exit;
+    // @ts-expect-error — overriding process.exit for test
+    process.exit = () => {};
+    try {
+      await daemon.shutdown();
+    } finally {
+      process.exit = origExit;
+    }
+
+    // Count health entries at shutdown
+    const contentAtShutdown = readFileSync(logPath, 'utf-8');
+    const healthCountAtShutdown = contentAtShutdown
+      .trim()
+      .split('\n')
+      .filter((l) => JSON.parse(l).msg === 'health').length;
+
+    // Wait another interval — no new health entries should appear
+    await new Promise((r) => setTimeout(r, 120));
+
+    // Re-read (logger is closed, so file shouldn't change)
+    const contentAfterWait = readFileSync(logPath, 'utf-8');
+    const healthCountAfterWait = contentAfterWait
+      .trim()
+      .split('\n')
+      .filter((l) => JSON.parse(l).msg === 'health').length;
+
+    assert.equal(
+      healthCountAfterWait,
+      healthCountAtShutdown,
+      'no new health entries should appear after shutdown',
+    );
+  });
+});
 
 describe('CLI integration', () => {
   it('--help prints usage and exits 0', () => {
diff --git a/packages/daemon/src/daemon.ts b/packages/daemon/src/daemon.ts
index f5bedfacb..7eb2c1670 100644
--- a/packages/daemon/src/daemon.ts
+++ b/packages/daemon/src/daemon.ts
@@ -13,6 +13,7 @@ import { Orchestrator } from './orchestrator.js';
 export class Daemon {
   private shuttingDown = false;
   private keepaliveTimer: ReturnType<typeof setInterval> | undefined;
+  private healthTimer: ReturnType<typeof setInterval> | undefined;
   private readonly onSigterm: () => void;
   private readonly onSigint: () => void;
   private sessionManager: SessionManager | undefined;
@@ -23,6 +24,7 @@ export class Daemon {
   constructor(
     private readonly config: DaemonConfig,
     private readonly logger: Logger,
+    private readonly healthIntervalMs: number = 300_000,
   ) {
     this.onSigterm = () => void this.shutdown();
     this.onSigint = () => void this.shutdown();
@@ -105,6 +107,21 @@ export class Daemon {
         this.discordBot = undefined;
       }
     }
+
+    // Health heartbeat — logs uptime, session count, Discord status, memory
+    const startTime = Date.now();
+    this.healthTimer = setInterval(() => {
+      const sessions = this.sessionManager?.getAllSessions() ?? [];
+      const activeSessions = sessions.filter(
+        (s) => s.status === 'running' || s.status === 'blocked',
+      ).length;
+      this.logger.info('health', {
+        uptime_s: Math.floor((Date.now() - startTime) / 1000),
+        active_sessions: activeSessions,
+        discord_connected: !!this.discordBot?.getClient()?.isReady(),
+        memory_rss_mb: Math.round(process.memoryUsage().rss / 1024 / 1024),
+      });
+    }, this.healthIntervalMs);
   }
 
   /** Scan configured project roots for project directories. */
@@ -141,6 +158,12 @@ export class Daemon {
     process.removeListener('SIGTERM', this.onSigterm);
     process.removeListener('SIGINT', this.onSigint);
 
+    // Clear health heartbeat timer
+    if (this.healthTimer) {
+      clearInterval(this.healthTimer);
+      this.healthTimer = undefined;
+    }
+
     // Clear keepalive so the event loop can drain
     if (this.keepaliveTimer) {
       clearInterval(this.keepaliveTimer);
diff --git a/packages/daemon/src/discord-bot.ts b/packages/daemon/src/discord-bot.ts
index 3edde49b5..94e6aeae7 100644
--- a/packages/daemon/src/discord-bot.ts
+++ b/packages/daemon/src/discord-bot.ts
@@ -129,6 +129,26 @@ export class DiscordBot {
       this.handleInteraction(interaction);
     });
 
+    // Reconnection observability — structured logging for all shard lifecycle events (R027)
+    client.on('shardError', (error) => {
+      this.logger.error('discord shard error', { error: error.message });
+    });
+    client.on('shardDisconnect', (event, shardId) => {
+      this.logger.warn('discord shard disconnected', { shardId, code: event.code });
+    });
+    client.on('shardReconnecting', (shardId) => {
+      this.logger.info('discord shard reconnecting', { shardId });
+    });
+    client.on('shardResume', (shardId, replayedEvents) => {
+      this.logger.info('discord shard resumed', { shardId, replayedEvents });
+    });
+    client.on('warn', (message) => {
+      this.logger.warn('discord warning', { message });
+    });
+    client.on('error', (error) => {
+      this.logger.error('discord error', { error: error.message });
+    });
+
     await client.login(this.config.token);
     this.client = client;
     this.destroyed = false;