diff --git a/src/agent/check-approval.ts b/src/agent/check-approval.ts
index c0cd15c..bb88586 100644
--- a/src/agent/check-approval.ts
+++ b/src/agent/check-approval.ts
@@ -6,7 +6,7 @@ import { APIError } from "@letta-ai/letta-client/core/error";
 import type { AgentState } from "@letta-ai/letta-client/resources/agents/agents";
 import type { Message } from "@letta-ai/letta-client/resources/agents/messages";
 import type { ApprovalRequest } from "../cli/helpers/stream";
-import { debugWarn } from "../utils/debug";
+import { debugLog, debugWarn } from "../utils/debug";
 
 // Backfill should feel like "the last turn(s)", not "the last N raw messages".
 // Tool-heavy turns can generate many tool_call/tool_return messages that would
@@ -344,16 +344,21 @@ export async function getResumeData(
 
     // Use conversations API for explicit conversations,
     // use agents API for "default" or no conversationId (agent's primary message history)
-    const useConversationsApi = conversationId && conversationId !== "default";
+    const useConversationsApi =
+      conversationId &&
+      conversationId !== "default" &&
+      !conversationId.startsWith("agent-");
 
-    if (process.env.DEBUG) {
-      console.log(
-        `[DEBUG] getResumeData: conversationId=${conversationId}, useConversationsApi=${useConversationsApi}, agentId=${agent.id}`,
+    if (conversationId?.startsWith("agent-")) {
+      debugWarn(
+        "check-approval",
+        `getResumeData called with agent ID as conversationId: ${conversationId}\n${new Error().stack}`,
       );
     }
 
     if (useConversationsApi) {
       // Get conversation to access in_context_message_ids (source of truth)
+      debugLog("conversations", `retrieve(${conversationId}) [getResumeData]`);
       const conversation = await client.conversations.retrieve(conversationId);
       inContextMessageIds = conversation.in_context_message_ids;
 
diff --git a/src/cli/App.tsx b/src/cli/App.tsx
index 9101bff..6afe942 100644
--- a/src/cli/App.tsx
+++ b/src/cli/App.tsx
@@ -3280,6 +3280,10 @@ export default function App({
 
       try {
         const client = await getClient();
+        debugLog(
+          "conversations",
+          `retrieve(${conversationId}) [syncConversationModel]`,
+        );
         const conversation =
           await client.conversations.retrieve(conversationId);
         if (cancelled) return;
@@ -6154,7 +6158,9 @@ export default function App({
         // Build success message
         const agentLabel = agent.name || targetAgentId;
         const isSpecificConv =
-          opts?.conversationId && opts.conversationId !== "default";
+          opts?.conversationId &&
+          opts.conversationId !== "default" &&
+          !opts?.conversationId.startsWith("agent-");
         const successOutput = isSpecificConv
           ? [
               `Switched to **${agentLabel}**`,
@@ -8695,7 +8701,7 @@ export default function App({
 
             // Build export parameters (include conversation_id if in specific conversation)
             const exportParams: { conversation_id?: string } = {};
-            if (conversationId !== "default") {
+            if (conversationId !== "default" && conversationId !== agentId) {
               exportParams.conversation_id = conversationId;
             }
 
@@ -12914,15 +12920,16 @@ If using apply_patch, use this exact relative patch path: ${applyPatchRelativePa
                         : `letta --agent ${agentId}`}
                     </Text>
                     {/* Only show conversation hint if not on default (default is resumed automatically) */}
-                    {conversationId !== "default" && (
-                      <>
-                        <Box height={1} />
-                        <Text dimColor>Resume this conversation with:</Text>
-                        <Text color={colors.link.url}>
-                          {`letta --conv ${conversationId}`}
-                        </Text>
-                      </>
-                    )}
+                    {conversationId !== "default" &&
+                      conversationId !== agentId && (
+                        <>
+                          <Box height={1} />
+                          <Text dimColor>Resume this conversation with:</Text>
+                          <Text color={colors.link.url}>
+                            {`letta --conv ${conversationId}`}
+                          </Text>
+                        </>
+                      )}
                   </Box>
                 );
               })()}
diff --git a/src/cli/components/AgentInfoBar.tsx b/src/cli/components/AgentInfoBar.tsx
index 7044356..e689949 100644
--- a/src/cli/components/AgentInfoBar.tsx
+++ b/src/cli/components/AgentInfoBar.tsx
@@ -177,7 +177,9 @@ export const AgentInfoBar = memo(function AgentInfoBar({
       {/* Phantom alien row + Conversation ID */}
       <Box>
         <Text>{alienLines[3]}</Text>
-        {conversationId && conversationId !== "default" ? (
+        {conversationId &&
+        conversationId !== "default" &&
+        !conversationId.startsWith("agent-") ? (
           <Box width={rightWidth} flexShrink={1}>
             <Text dimColor wrap="truncate-end">
               {truncateText(conversationId, rightWidth)}
diff --git a/src/headless.ts b/src/headless.ts
index 795b86b..d43158e 100644
--- a/src/headless.ts
+++ b/src/headless.ts
@@ -114,6 +114,7 @@ import type {
   StreamEvent,
   SystemInitMessage,
 } from "./types/protocol";
+import { debugLog } from "./utils/debug";
 import {
   markMilestone,
   measureSinceMilestone,
@@ -526,7 +527,10 @@ export async function handleHeadlessCommand(
   // Validate shared mutual-exclusion rules for startup flags.
   try {
     validateFlagConflicts({
-      guard: specifiedConversationId && specifiedConversationId !== "default",
+      guard:
+        specifiedConversationId &&
+        specifiedConversationId !== "default" &&
+        !specifiedConversationId.startsWith("agent-"),
       checks: [
         {
           when: specifiedAgentId,
@@ -730,8 +734,16 @@ export async function handleHeadlessCommand(
   // Priority 0: --conversation derives agent from conversation ID.
   // "default" is a virtual agent-scoped conversation (not a retrievable conv-*).
   // It requires --agent and should not hit conversations.retrieve().
-  if (specifiedConversationId && specifiedConversationId !== "default") {
+  if (
+    specifiedConversationId &&
+    specifiedConversationId !== "default" &&
+    !specifiedConversationId.startsWith("agent-")
+  ) {
     try {
+      debugLog(
+        "conversations",
+        `retrieve(${specifiedConversationId}) [headless conv→agent lookup]`,
+      );
       const conversation = await client.conversations.retrieve(
         specifiedConversationId,
       );
@@ -1007,6 +1019,10 @@ export async function handleHeadlessCommand(
     } else {
       // User specified an explicit conversation to resume - validate it exists
       try {
+        debugLog(
+          "conversations",
+          `retrieve(${specifiedConversationId}) [headless --conv validate]`,
+        );
         await client.conversations.retrieve(specifiedConversationId);
         conversationId = specifiedConversationId;
       } catch {
@@ -1030,6 +1046,10 @@ export async function handleHeadlessCommand(
       } else {
         // Verify the conversation still exists
         try {
+          debugLog(
+            "conversations",
+            `retrieve(${lastSession.conversationId}) [headless lastSession resume]`,
+          );
           await client.conversations.retrieve(lastSession.conversationId);
           conversationId = lastSession.conversationId;
         } catch {
diff --git a/src/index.ts b/src/index.ts
index 62085e3..17ed4a9 100755
--- a/src/index.ts
+++ b/src/index.ts
@@ -47,6 +47,7 @@ import { settingsManager } from "./settings-manager";
 import { startStartupAutoUpdateCheck } from "./startup-auto-update";
 import { telemetry } from "./telemetry";
 import { loadTools } from "./tools/manager";
+import { debugLog } from "./utils/debug";
 import { markMilestone } from "./utils/timing";
 
 // Stable empty array constants to prevent new references on every render
@@ -629,7 +630,10 @@ async function main(): Promise<void> {
   // Validate shared mutual-exclusion rules for startup flags.
   try {
     validateFlagConflicts({
-      guard: specifiedConversationId && specifiedConversationId !== "default",
+      guard:
+        specifiedConversationId &&
+        specifiedConversationId !== "default" &&
+        !specifiedConversationId.startsWith("agent-"),
       checks: [
         {
           when: specifiedAgentId,
@@ -1193,6 +1197,10 @@ async function main(): Promise<void> {
 
           // For explicit conversations, derive agent from conversation
           try {
+            debugLog(
+              "conversations",
+              `retrieve(${specifiedConversationId}) [TUI conv→agent lookup]`,
+            );
             const conversation = await client.conversations.retrieve(
               specifiedConversationId,
             );