diff --git a/gitnexus/src/cli/ai-context.ts b/gitnexus/src/cli/ai-context.ts
index 89bf912f0..32295769e 100644
--- a/gitnexus/src/cli/ai-context.ts
+++ b/gitnexus/src/cli/ai-context.ts
@@ -381,9 +381,6 @@ async function upsertGitNexusSection(
       // drop the parenthetical but still refresh the project name so renames
       // propagate.
       const newStatsInner = `${stats.nodes || 0} symbols, ${stats.edges || 0} relationships, ${stats.processes || 0} execution flows`;
-      const statsLine = noStats
-        ? `Indexed as **${projectName}**`
-        : `Indexed as **${projectName}** (${newStatsInner})`;
 
       // Match either canonical phrasing at line start (`^` with `m` flag) so we
       // cannot replace prose embedded mid-paragraph. Deliberately no `$`: text
@@ -391,10 +388,15 @@ async function upsertGitNexusSection(
       // The parenthetical is optional so a count-free line left by a prior
       // --no-stats run still matches — letting the name refresh, and letting
       // counts return if --no-stats is later dropped.
-      const statsPattern = /^(?:Indexed as|indexed by GitNexus as) \*\*[^*]+\*\*(?: \([^)]+\))?/m;
+      const statsPattern = /^(Indexed as|indexed by GitNexus as) \*\*[^*]+\*\*(?: \([^)]+\))?/m;
+      const statsMatch = existingSection.match(statsPattern);
 
-      if (statsPattern.test(existingSection)) {
-        const updatedSection = existingSection.replace(statsPattern, statsLine);
+      if (statsMatch) {
+        const statsPrefix = statsMatch[1];
+        const statsLine = noStats
+          ? `${statsPrefix} **${projectName}**`
+          : `${statsPrefix} **${projectName}** (${newStatsInner})`;
+        const updatedSection = existingSection.replace(statsPattern, () => statsLine);
         // Count-only delta — leave the committed lean block alone (#2907). A
         // project rename, or --no-stats dropping the parenthetical, still writes.
         if (stripVolatileCounts(updatedSection) === stripVolatileCounts(existingSection)) {
diff --git a/gitnexus/test/unit/ai-context.test.ts b/gitnexus/test/unit/ai-context.test.ts
index a7174e674..d35236974 100644
--- a/gitnexus/test/unit/ai-context.test.ts
+++ b/gitnexus/test/unit/ai-context.test.ts
@@ -1722,4 +1722,33 @@ Indexed as **${name}**${counts}. Lean block.
       await fs.rm(dir, { recursive: true, force: true });
     }
   });
+
+  it('preserves the existing stats-line prefix when updating a keep marker', async () => {
+    const dir = await fs.mkdtemp(path.join(os.tmpdir(), 'gn-keep-prefix-'));
+    const storage = path.join(dir, '.gitnexus');
+    await fs.mkdir(storage, { recursive: true });
+    try {
+      const original = `# Guide
+
+<!-- gitnexus:start -->
+<!-- gitnexus:keep -->
+indexed by GitNexus as **OldName** (10 symbols, 20 relationships, 3 execution flows). Custom.
+<!-- gitnexus:end -->
+`;
+      await fs.writeFile(path.join(dir, 'CLAUDE.md'), original, 'utf-8');
+
+      const result = await generateAIContextFiles(dir, storage, 'Repo$1Name', {
+        nodes: 55,
+        edges: 66,
+        processes: 7,
+      });
+
+      expect(result.files).toContain('CLAUDE.md (updated)');
+      expect(await fs.readFile(path.join(dir, 'CLAUDE.md'), 'utf-8')).toContain(
+        'indexed by GitNexus as **Repo$1Name** (55 symbols, 66 relationships, 7 execution flows). Custom.',
+      );
+    } finally {
+      await fs.rm(dir, { recursive: true, force: true });
+    }
+  });
 });