fix(cli): tighten attach feedback and default dedupe semantics

Author: cdenneen

apps/cli/src/channels/core/channelBridgeWorker.test.ts

@@ -195,6 +195,40 @@ describe('executeChannelBridgeTick', () => {
     ]);
   });
 
+  it('includes previous session id when /attach replaces an existing binding', async () => {
+    const store = createInMemoryChannelBindingStore();
+    const harness = createAdapterHarness();
+
+    await store.upsertBinding({
+      providerId: 'telegram',
+      conversationId: '-1001',
+      threadId: '88',
+      sessionId: 'sess-old',
+      lastForwardedSeq: 12,
+    });
+
+    const { deps } = createDepsHarness({
+      resolveSessionIdOrPrefix: async () => ({ ok: true as const, sessionId: 'sess-new' }),
+      resolveLatestSessionSeq: async () => 41,
+    });
+
+    harness.pushInbound({
+      providerId: 'telegram',
+      conversationId: '-1001',
+      threadId: '88',
+      text: '/attach sess-new',
+      messageId: 'm-attach-replace',
+    });
+
+    await executeChannelBridgeTick({
+      store,
+      adapters: [harness.adapter],
+      deps,
+    });
+
+    expect(harness.sent.some((row) => row.text.includes('replaced previous session sess-old'))).toBe(true);
+  });
+
   it('supports /sessions and /detach command flow', async () => {
     const store = createInMemoryChannelBindingStore();
     const harness = createAdapterHarness();
@@ -500,6 +534,44 @@ describe('executeChannelBridgeTick', () => {
     expect(binding?.lastForwardedSeq).toBe(10);
     expect(warnings.some((row) => row.message.includes('Failed to forward agent output to channel'))).toBe(true);
   });
+
+  it('deduplicates repeated inbound messages across direct executeChannelBridgeTick calls', async () => {
+    const store = createInMemoryChannelBindingStore();
+    const harness = createAdapterHarness();
+
+    await store.upsertBinding({
+      providerId: 'telegram',
+      conversationId: 'direct-dedupe-room',
+      threadId: null,
+      sessionId: 'sess-direct-dedupe',
+      lastForwardedSeq: 0,
+    });
+
+    const { deps, sentToSession } = createDepsHarness();
+    const repeated = {
+      providerId: 'telegram' as const,
+      conversationId: 'direct-dedupe-room',
+      threadId: null,
+      text: 'same payload',
+      messageId: 'direct-dedupe-id-1',
+    };
+
+    harness.pushInbound(repeated);
+    await executeChannelBridgeTick({
+      store,
+      adapters: [harness.adapter],
+      deps,
+    });
+
+    harness.pushInbound(repeated);
+    await executeChannelBridgeTick({
+      store,
+      adapters: [harness.adapter],
+      deps,
+    });
+
+    expect(sentToSession).toHaveLength(1);
+  });
 });
 
 describe('startChannelBridgeWorker', () => {

apps/cli/src/channels/core/channelBridgeWorker.ts

@@ -137,6 +137,8 @@ type ChannelBridgeInboundDeduper = Readonly<{
   isDuplicate: (message: ChannelBridgeInboundMessage) => boolean;
 }>;
 
+const sharedInboundDeduper = createChannelBridgeInboundDeduper();
+
 function createChannelBridgeInboundDeduper(now: () => number = () => Date.now()): ChannelBridgeInboundDeduper {
   const recent = new Map<string, number>();
   const ttlMs = 5 * 60 * 1000;
@@ -332,6 +334,9 @@ async function handleCommand(params: Readonly<{
       return true;
     }
 
+    const previousBinding = await store.getBinding(ref);
+    const previousSessionId = previousBinding?.sessionId ?? null;
+
     await store.upsertBinding({
       providerId: ref.providerId,
       conversationId: ref.conversationId,
@@ -340,7 +345,11 @@ async function handleCommand(params: Readonly<{
       lastForwardedSeq: latestSeq,
     });
 
-    await replyToConversation(adapter, ref, `Attached this conversation to session ${resolved.sessionId}.`);
+    const switchedFrom =
+      previousSessionId && previousSessionId !== resolved.sessionId
+        ? ` (replaced previous session ${previousSessionId})`
+        : '';
+    await replyToConversation(adapter, ref, `Attached this conversation to session ${resolved.sessionId}${switchedFrom}.`);
     return true;
   }
 
@@ -385,7 +394,7 @@ export async function executeChannelBridgeTick(params: Readonly<{
     activeAdapters.push(adapter);
   }
 
-  const deduper = params.inboundDeduper ?? createChannelBridgeInboundDeduper();
+  const deduper = params.inboundDeduper ?? sharedInboundDeduper;
 
   for (const adapter of activeAdapters) {
     let inbound: ChannelBridgeInboundMessage[];