fix: harden heartbeat acks + gateway reconnect

src/agents/system-prompt.ts

@@ -95,6 +95,7 @@ export function buildAgentSystemPromptAppend(params: {
     "## Heartbeats",
     'If you receive a heartbeat poll (a user message containing just "HEARTBEAT"), and there is nothing that needs attention, reply exactly:',
     "HEARTBEAT_OK",
+    'Any response containing "HEARTBEAT_OK" is treated as a heartbeat ack and will not be delivered.',
     'If something needs attention, do NOT include "HEARTBEAT_OK"; reply with the alert text instead.',
     "",
     "## Runtime",

src/auto-reply/heartbeat.test.ts

@@ -19,18 +19,15 @@ describe("stripHeartbeatToken", () => {
     });
   });
 
-  it("keeps content and removes token when mixed", () => {
+  it("skips any reply that includes the heartbeat token", () => {
     expect(stripHeartbeatToken(`ALERT ${HEARTBEAT_TOKEN}`)).toEqual({
-      shouldSkip: false,
-      text: "ALERT",
+      shouldSkip: true,
+      text: "",
     });
-    expect(stripHeartbeatToken("hello")).toEqual({
-      shouldSkip: false,
-      text: "hello",
+    expect(stripHeartbeatToken("HEARTBEAT_OK 🦞")).toEqual({
+      shouldSkip: true,
+      text: "",
     });
-  });
-
-  it("strips repeated OK tails after heartbeat token", () => {
     expect(stripHeartbeatToken("HEARTBEAT_OK_OK_OK")).toEqual({
       shouldSkip: true,
       text: "",
@@ -48,8 +45,15 @@ describe("stripHeartbeatToken", () => {
       text: "",
     });
     expect(stripHeartbeatToken("ALERT HEARTBEAT_OK_OK")).toEqual({
+      shouldSkip: true,
+      text: "",
+    });
+  });
+
+  it("keeps non-heartbeat content", () => {
+    expect(stripHeartbeatToken("hello")).toEqual({
       shouldSkip: false,
-      text: "ALERT",
+      text: "hello",
     });
   });
 });

src/auto-reply/heartbeat.ts

@@ -6,16 +6,8 @@ export function stripHeartbeatToken(raw?: string) {
   if (!raw) return { shouldSkip: true, text: "" };
   const trimmed = raw.trim();
   if (!trimmed) return { shouldSkip: true, text: "" };
-  if (trimmed === HEARTBEAT_TOKEN) return { shouldSkip: true, text: "" };
-  const hadToken = trimmed.includes(HEARTBEAT_TOKEN);
-  let withoutToken = trimmed.replaceAll(HEARTBEAT_TOKEN, "").trim();
-  if (hadToken && withoutToken) {
-    // LLMs sometimes echo malformed HEARTBEAT_OK_OK... tails; strip trailing OK runs to avoid spam.
-    withoutToken = withoutToken.replace(/[\s_]*OK(?:[\s_]*OK)*$/gi, "").trim();
+  if (trimmed.includes(HEARTBEAT_TOKEN)) {
+    return { shouldSkip: true, text: "" };
   }
-  const shouldSkip = withoutToken.length === 0;
-  return {
-    shouldSkip,
-    text: shouldSkip ? "" : withoutToken || trimmed,
-  };
+  return { shouldSkip: false, text: trimmed };
 }