diff --git a/src/agents/agent-scope.ts b/src/agents/agent-scope.ts
index 266ed8a63..b252345ec 100644
--- a/src/agents/agent-scope.ts
+++ b/src/agents/agent-scope.ts
@@ -3,7 +3,11 @@ import path from "node:path";
 
 import type { ClawdbotConfig } from "../config/config.js";
 import { resolveStateDir } from "../config/paths.js";
-import { DEFAULT_AGENT_ID, normalizeAgentId } from "../routing/session-key.js";
+import {
+  DEFAULT_AGENT_ID,
+  normalizeAgentId,
+  parseAgentSessionKey,
+} from "../routing/session-key.js";
 import { resolveUserPath } from "../utils.js";
 import { DEFAULT_AGENT_WORKSPACE_DIR } from "./workspace.js";
 
@@ -49,6 +53,26 @@ export function resolveDefaultAgentId(cfg: ClawdbotConfig): string {
   return normalizeAgentId(chosen || DEFAULT_AGENT_ID);
 }
 
+export function resolveSessionAgentIds(params: {
+  sessionKey?: string;
+  config?: ClawdbotConfig;
+}): { defaultAgentId: string; sessionAgentId: string } {
+  const defaultAgentId = resolveDefaultAgentId(params.config ?? {});
+  const sessionKey = params.sessionKey?.trim();
+  const parsed = sessionKey ? parseAgentSessionKey(sessionKey) : null;
+  const sessionAgentId = parsed?.agentId
+    ? normalizeAgentId(parsed.agentId)
+    : defaultAgentId;
+  return { defaultAgentId, sessionAgentId };
+}
+
+export function resolveSessionAgentId(params: {
+  sessionKey?: string;
+  config?: ClawdbotConfig;
+}): string {
+  return resolveSessionAgentIds(params).sessionAgentId;
+}
+
 function resolveAgentEntry(
   cfg: ClawdbotConfig,
   agentId: string,
diff --git a/src/agents/claude-cli-runner.ts b/src/agents/claude-cli-runner.ts
index 5497ddb97..b56afd360 100644
--- a/src/agents/claude-cli-runner.ts
+++ b/src/agents/claude-cli-runner.ts
@@ -9,6 +9,7 @@ import { shouldLogVerbose } from "../globals.js";
 import { createSubsystemLogger } from "../logging.js";
 import { runCommandWithTimeout } from "../process/exec.js";
 import { resolveUserPath } from "../utils.js";
+import { resolveSessionAgentIds } from "./agent-scope.js";
 import { FailoverError, resolveFailoverStatus } from "./failover-error.js";
 import {
   buildBootstrapContextFiles,
@@ -136,6 +137,7 @@ function buildSystemPrompt(params: {
   defaultThinkLevel?: ThinkLevel;
   extraSystemPrompt?: string;
   ownerNumbers?: string[];
+  heartbeatPrompt?: string;
   tools: AgentTool[];
   contextFiles?: EmbeddedContextFile[];
   modelDisplay: string;
@@ -150,9 +152,7 @@ function buildSystemPrompt(params: {
     extraSystemPrompt: params.extraSystemPrompt,
     ownerNumbers: params.ownerNumbers,
     reasoningTagHint: false,
-    heartbeatPrompt: resolveHeartbeatPrompt(
-      params.config?.agents?.defaults?.heartbeat?.prompt,
-    ),
+    heartbeatPrompt: params.heartbeatPrompt,
     runtimeInfo: {
       host: "clawdbot",
       os: `${os.type()} ${os.release()}`,
@@ -374,12 +374,23 @@ export async function runClaudeCliAgent(params: {
     params.sessionKey ?? params.sessionId,
   );
   const contextFiles = buildBootstrapContextFiles(bootstrapFiles);
+  const { defaultAgentId, sessionAgentId } = resolveSessionAgentIds({
+    sessionKey: params.sessionKey,
+    config: params.config,
+  });
+  const heartbeatPrompt =
+    sessionAgentId === defaultAgentId
+      ? resolveHeartbeatPrompt(
+          params.config?.agents?.defaults?.heartbeat?.prompt,
+        )
+      : undefined;
   const systemPrompt = buildSystemPrompt({
     workspaceDir,
     config: params.config,
     defaultThinkLevel: params.thinkLevel,
     extraSystemPrompt,
     ownerNumbers: params.ownerNumbers,
+    heartbeatPrompt,
     tools: [],
     contextFiles,
     modelDisplay,
diff --git a/src/agents/pi-embedded-runner.test.ts b/src/agents/pi-embedded-runner.test.ts
index f44a337c6..6d8a5f213 100644
--- a/src/agents/pi-embedded-runner.test.ts
+++ b/src/agents/pi-embedded-runner.test.ts
@@ -3,11 +3,11 @@ import { SessionManager } from "@mariozechner/pi-coding-agent";
 import { Type } from "@sinclair/typebox";
 import { describe, expect, it, vi } from "vitest";
 import type { ClawdbotConfig } from "../config/config.js";
+import { resolveSessionAgentIds } from "./agent-scope.js";
 import {
   applyGoogleTurnOrderingFix,
   buildEmbeddedSandboxInfo,
   createSystemPromptOverride,
-  resolveSessionAgentIds,
   splitSdkTools,
 } from "./pi-embedded-runner.js";
 import type { SandboxContext } from "./sandbox.js";
@@ -82,6 +82,22 @@ describe("resolveSessionAgentIds", () => {
     expect(sessionAgentId).toBe("beta");
   });
 
+  it("falls back to the configured default for global sessions", () => {
+    const { sessionAgentId } = resolveSessionAgentIds({
+      sessionKey: "global",
+      config: cfg,
+    });
+    expect(sessionAgentId).toBe("beta");
+  });
+
+  it("keeps the agent id for provider-qualified agent sessions", () => {
+    const { sessionAgentId } = resolveSessionAgentIds({
+      sessionKey: "agent:beta:slack:channel:C1",
+      config: cfg,
+    });
+    expect(sessionAgentId).toBe("beta");
+  });
+
   it("uses the agent id from agent session keys", () => {
     const { sessionAgentId } = resolveSessionAgentIds({
       sessionKey: "agent:main:main",
diff --git a/src/agents/pi-embedded-runner.ts b/src/agents/pi-embedded-runner.ts
index f2fc0ae35..d3a73a002 100644
--- a/src/agents/pi-embedded-runner.ts
+++ b/src/agents/pi-embedded-runner.ts
@@ -33,14 +33,10 @@ import {
   type enqueueCommand,
   enqueueCommandInLane,
 } from "../process/command-queue.js";
-import {
-  normalizeAgentId,
-  parseAgentSessionKey,
-} from "../routing/session-key.js";
 import { normalizeMessageProvider } from "../utils/message-provider.js";
 import { resolveUserPath } from "../utils.js";
 import { resolveClawdbotAgentDir } from "./agent-paths.js";
-import { resolveDefaultAgentId } from "./agent-scope.js";
+import { resolveSessionAgentIds } from "./agent-scope.js";
 import {
   markAuthProfileFailure,
   markAuthProfileGood,
@@ -560,19 +556,6 @@ export function buildEmbeddedSandboxInfo(
   };
 }
 
-export function resolveSessionAgentIds(params: {
-  sessionKey?: string;
-  config?: ClawdbotConfig;
-}): { defaultAgentId: string; sessionAgentId: string } {
-  const defaultAgentId = resolveDefaultAgentId(params.config ?? {});
-  const sessionKey = params.sessionKey?.trim();
-  const parsed = sessionKey ? parseAgentSessionKey(sessionKey) : null;
-  const sessionAgentId = parsed?.agentId
-    ? normalizeAgentId(parsed.agentId)
-    : defaultAgentId;
-  return { defaultAgentId, sessionAgentId };
-}
-
 function buildEmbeddedSystemPrompt(params: {
   workspaceDir: string;
   defaultThinkLevel?: ThinkLevel;
diff --git a/src/auto-reply/reply.ts b/src/auto-reply/reply.ts
index 9370dfc58..c6dbfac00 100644
--- a/src/auto-reply/reply.ts
+++ b/src/auto-reply/reply.ts
@@ -5,8 +5,8 @@ import { fileURLToPath } from "node:url";
 import {
   resolveAgentConfig,
   resolveAgentDir,
-  resolveAgentIdFromSessionKey,
   resolveAgentWorkspaceDir,
+  resolveSessionAgentId,
 } from "../agents/agent-scope.js";
 import { resolveModelRefFromString } from "../agents/model-selection.js";
 import {
@@ -250,7 +250,10 @@ export async function getReplyFromConfig(
   configOverride?: ClawdbotConfig,
 ): Promise<ReplyPayload | ReplyPayload[] | undefined> {
   const cfg = configOverride ?? loadConfig();
-  const agentId = resolveAgentIdFromSessionKey(ctx.SessionKey);
+  const agentId = resolveSessionAgentId({
+    sessionKey: ctx.SessionKey,
+    config: cfg,
+  });
   const agentCfg = cfg.agents?.defaults;
   const sessionCfg = cfg.session;
   const { defaultProvider, defaultModel, aliasIndex } = resolveDefaultModel({
diff --git a/src/auto-reply/reply/abort.ts b/src/auto-reply/reply/abort.ts
index f06948626..3543cf739 100644
--- a/src/auto-reply/reply/abort.ts
+++ b/src/auto-reply/reply/abort.ts
@@ -1,3 +1,4 @@
+import { resolveSessionAgentId } from "../../agents/agent-scope.js";
 import { abortEmbeddedPiRun } from "../../agents/pi-embedded.js";
 import type { ClawdbotConfig } from "../../config/config.js";
 import {
@@ -7,10 +8,7 @@ import {
   saveSessionStore,
   type SessionEntry,
 } from "../../config/sessions.js";
-import {
-  parseAgentSessionKey,
-  resolveAgentIdFromSessionKey,
-} from "../../routing/session-key.js";
+import { parseAgentSessionKey } from "../../routing/session-key.js";
 import { resolveCommandAuthorization } from "../command-auth.js";
 import {
   normalizeCommandBody,
@@ -80,9 +78,10 @@ export async function tryFastAbortFromMessage(params: {
   if (!auth.isAuthorizedSender) return { handled: false, aborted: false };
 
   const targetKey = resolveAbortTargetKey(ctx);
-  const agentId = resolveAgentIdFromSessionKey(
-    targetKey ?? ctx.SessionKey ?? "",
-  );
+  const agentId = resolveSessionAgentId({
+    sessionKey: targetKey ?? ctx.SessionKey ?? "",
+    config: cfg,
+  });
   const raw = stripStructuralPrefixes(ctx.Body ?? "");
   const isGroup = ctx.ChatType?.trim().toLowerCase() === "group";
   const stripped = isGroup ? stripMentions(raw, ctx, cfg, agentId) : raw;
diff --git a/src/auto-reply/reply/commands.ts b/src/auto-reply/reply/commands.ts
index fb2f01aeb..3cd6a060f 100644
--- a/src/auto-reply/reply/commands.ts
+++ b/src/auto-reply/reply/commands.ts
@@ -1,6 +1,7 @@
 import {
   resolveAgentDir,
   resolveDefaultAgentId,
+  resolveSessionAgentId,
 } from "../../agents/agent-scope.js";
 import {
   ensureAuthProfileStore,
@@ -26,7 +27,6 @@ import {
   unsetConfigOverride,
 } from "../../config/runtime-overrides.js";
 import {
-  resolveAgentIdFromSessionKey,
   resolveSessionFilePath,
   type SessionEntry,
   type SessionScope,
@@ -148,7 +148,7 @@ export async function buildStatusReply(params: {
     return undefined;
   }
   const statusAgentId = sessionKey
-    ? resolveAgentIdFromSessionKey(sessionKey)
+    ? resolveSessionAgentId({ sessionKey, config: cfg })
     : resolveDefaultAgentId(cfg);
   const statusAgentDir = resolveAgentDir(cfg, statusAgentId);
   let usageLine: string | null = null;
diff --git a/src/auto-reply/reply/directive-handling.ts b/src/auto-reply/reply/directive-handling.ts
index fb5479da6..37f7e6698 100644
--- a/src/auto-reply/reply/directive-handling.ts
+++ b/src/auto-reply/reply/directive-handling.ts
@@ -2,6 +2,7 @@ import {
   resolveAgentConfig,
   resolveAgentDir,
   resolveDefaultAgentId,
+  resolveSessionAgentId,
 } from "../../agents/agent-scope.js";
 import {
   isProfileInCooldown,
@@ -31,7 +32,6 @@ import {
 import { resolveSandboxConfigForAgent } from "../../agents/sandbox.js";
 import type { ClawdbotConfig } from "../../config/config.js";
 import {
-  resolveAgentIdFromSessionKey,
   resolveAgentMainSessionKey,
   type SessionEntry,
   saveSessionStore,
@@ -491,14 +491,18 @@ export async function handleDirectiveOnly(params: {
     currentReasoningLevel,
     currentElevatedLevel,
   } = params;
-  const activeAgentId = params.sessionKey
-    ? resolveAgentIdFromSessionKey(params.sessionKey)
-    : resolveDefaultAgentId(params.cfg);
+  const activeAgentId = resolveSessionAgentId({
+    sessionKey: params.sessionKey,
+    config: params.cfg,
+  });
   const agentDir = resolveAgentDir(params.cfg, activeAgentId);
   const runtimeIsSandboxed = (() => {
     const sessionKey = params.sessionKey?.trim();
     if (!sessionKey) return false;
-    const agentId = resolveAgentIdFromSessionKey(sessionKey);
+    const agentId = resolveSessionAgentId({
+      sessionKey,
+      config: params.cfg,
+    });
     const sandboxCfg = resolveSandboxConfigForAgent(params.cfg, agentId);
     if (sandboxCfg.mode === "off") return false;
     const mainKey = resolveAgentMainSessionKey({
@@ -1013,7 +1017,7 @@ export async function persistInlineDirectives(params: {
   } = params;
   let { provider, model } = params;
   const activeAgentId = sessionKey
-    ? resolveAgentIdFromSessionKey(sessionKey)
+    ? resolveSessionAgentId({ sessionKey, config: cfg })
     : resolveDefaultAgentId(cfg);
   const agentDir = resolveAgentDir(cfg, activeAgentId);
 
diff --git a/src/auto-reply/reply/route-reply.ts b/src/auto-reply/reply/route-reply.ts
index 0258ef797..1e3eaf8a8 100644
--- a/src/auto-reply/reply/route-reply.ts
+++ b/src/auto-reply/reply/route-reply.ts
@@ -7,12 +7,12 @@
  * across multiple providers.
  */
 
+import { resolveSessionAgentId } from "../../agents/agent-scope.js";
 import { resolveEffectiveMessagesConfig } from "../../agents/identity.js";
 import type { ClawdbotConfig } from "../../config/config.js";
 import { sendMessageDiscord } from "../../discord/send.js";
 import { sendMessageIMessage } from "../../imessage/send.js";
 import { sendMessageMSTeams } from "../../msteams/send.js";
-import { resolveAgentIdFromSessionKey } from "../../routing/session-key.js";
 import { sendMessageSignal } from "../../signal/send.js";
 import { sendMessageSlack } from "../../slack/send.js";
 import { sendMessageTelegram } from "../../telegram/send.js";
@@ -67,7 +67,10 @@ export async function routeReply(
   const responsePrefix = params.sessionKey
     ? resolveEffectiveMessagesConfig(
         cfg,
-        resolveAgentIdFromSessionKey(params.sessionKey),
+        resolveSessionAgentId({
+          sessionKey: params.sessionKey,
+          config: cfg,
+        }),
       ).responsePrefix
     : cfg.messages?.responsePrefix === "auto"
       ? undefined
diff --git a/src/auto-reply/reply/session.ts b/src/auto-reply/reply/session.ts
index 94a6b8c60..1f11cef14 100644
--- a/src/auto-reply/reply/session.ts
+++ b/src/auto-reply/reply/session.ts
@@ -6,6 +6,7 @@ import {
   CURRENT_SESSION_VERSION,
   SessionManager,
 } from "@mariozechner/pi-coding-agent";
+import { resolveSessionAgentId } from "../../agents/agent-scope.js";
 import type { ClawdbotConfig } from "../../config/config.js";
 import {
   buildGroupDisplayName,
@@ -13,7 +14,6 @@ import {
   DEFAULT_RESET_TRIGGERS,
   type GroupKeyResolution,
   loadSessionStore,
-  resolveAgentIdFromSessionKey,
   resolveGroupSessionKey,
   resolveSessionFilePath,
   resolveSessionKey,
@@ -92,7 +92,10 @@ export async function initSessionState(params: {
   const { ctx, cfg, commandAuthorized } = params;
   const sessionCfg = cfg.session;
   const mainKey = normalizeMainKey(sessionCfg?.mainKey);
-  const agentId = resolveAgentIdFromSessionKey(ctx.SessionKey);
+  const agentId = resolveSessionAgentId({
+    sessionKey: ctx.SessionKey,
+    config: cfg,
+  });
   const resetTriggers = sessionCfg?.resetTriggers?.length
     ? sessionCfg.resetTriggers
     : DEFAULT_RESET_TRIGGERS;