diff --git a/assistant/src/daemon/handlers/sessions.ts b/assistant/src/daemon/handlers/sessions.ts
index 58bb59f52f6..98be1e24308 100644
--- a/assistant/src/daemon/handlers/sessions.ts
+++ b/assistant/src/daemon/handlers/sessions.ts
@@ -740,10 +740,12 @@ export function handleHistoryRequest(
 
     // Apply text truncation when maxTextChars is set
     let wasTruncated = false;
+    let textWasTruncated = false;
     let text = m.text;
     if (msg.maxTextChars !== undefined && text.length > msg.maxTextChars) {
       text = text.slice(0, msg.maxTextChars) + ' \u2026 [truncated]';
       wasTruncated = true;
+      textWasTruncated = true;
     }
 
     // Apply tool result truncation when maxToolResultChars is set
@@ -764,8 +766,8 @@ export function handleHistoryRequest(
       timestamp: m.timestamp,
       ...(truncatedToolCalls.length > 0 ? { toolCalls: truncatedToolCalls, toolCallsBeforeText: m.toolCallsBeforeText } : {}),
       ...(attachments ? { attachments } : {}),
-      ...(!wasTruncated && m.textSegments.length > 0 ? { textSegments: m.textSegments } : {}),
-      ...(!wasTruncated && m.contentOrder.length > 0 ? { contentOrder: m.contentOrder } : {}),
+      ...(!textWasTruncated && m.textSegments.length > 0 ? { textSegments: m.textSegments } : {}),
+      ...(!textWasTruncated && m.contentOrder.length > 0 ? { contentOrder: m.contentOrder } : {}),
       ...(filteredSurfaces.length > 0 ? { surfaces: filteredSurfaces } : {}),
       ...(m.subagentNotification ? { subagentNotification: m.subagentNotification } : {}),
       ...(wasTruncated ? { wasTruncated: true } : {}),
@@ -933,7 +935,7 @@ export function handleMessageContentRequest(
     // following user message rather than inline with the assistant message.
     // This mirrors the mergeToolResults logic used by handleHistoryRequest.
     if (dbMessage.role === 'assistant' && mergedToolCalls.some((tc) => tc.result === undefined)) {
-      const nextMsg = conversationStore.getNextMessage(msg.sessionId, dbMessage.createdAt);
+      const nextMsg = conversationStore.getNextMessage(msg.sessionId, dbMessage.createdAt, dbMessage.id);
       if (nextMsg && nextMsg.role === 'user') {
         try {
           const nextContent = JSON.parse(nextMsg.content);
diff --git a/assistant/src/memory/conversation-store.ts b/assistant/src/memory/conversation-store.ts
index cbb17b3b2a4..ece69f8e6e8 100644
--- a/assistant/src/memory/conversation-store.ts
+++ b/assistant/src/memory/conversation-store.ts
@@ -1,4 +1,4 @@
-import { and, asc, count, desc, eq, gt, inArray, isNull, lt, lte, ne, sql } from 'drizzle-orm';
+import { and, asc, count, desc, eq, gt, gte, inArray, isNull, lt, lte, ne, sql } from 'drizzle-orm';
 import { v4 as uuid } from 'uuid';
 import { z } from 'zod';
 
@@ -339,17 +339,20 @@ export function getMessageById(messageId: string, conversationId?: string): Mess
 }
 
 /**
- * Get the next message in a conversation after a given message (by timestamp).
- * Used for legacy tool_result merging in the rehydrate endpoint.
+ * Get the next message in a conversation after a given message.
+ * Uses gte + ne(id) instead of gt on timestamp so that messages sharing the
+ * same millisecond (common in legacy conversations where an assistant turn and
+ * the following user tool_result are saved in the same tick) are not skipped.
  */
-export function getNextMessage(conversationId: string, afterTimestamp: number): MessageRow | null {
+export function getNextMessage(conversationId: string, afterTimestamp: number, excludeMessageId: string): MessageRow | null {
   const db = getDb();
   const row = db
     .select()
     .from(messages)
     .where(and(
       eq(messages.conversationId, conversationId),
-      gt(messages.createdAt, afterTimestamp),
+      gte(messages.createdAt, afterTimestamp),
+      ne(messages.id, excludeMessageId),
     ))
     .orderBy(asc(messages.createdAt))
     .limit(1)