diff --git a/packages/agents/src/commands/__tests__/install.test.ts b/packages/agents/src/commands/__tests__/install.test.ts
index 3a29e62d..a9eff743 100644
--- a/packages/agents/src/commands/__tests__/install.test.ts
+++ b/packages/agents/src/commands/__tests__/install.test.ts
@@ -58,6 +58,22 @@ describe(installCommand, () => {
     expect(manifest.harnesses.claude?.entries.length).toBeGreaterThan(0);
   });
 
+  it('skips a support directory that renders to zero installable entries', async () => {
+    const claudeHome = await setupClaudeHome();
+    // A support directory whose only content is a dotfile renders to zero entries (the renderer skips dotfiles),
+    // so install must skip it rather than create anything.
+    const emptySupportSrc = path.join(contentDir, 'skills', 'empty-support');
+    await mkdir(emptySupportSrc, { recursive: true });
+    await writeFile(path.join(emptySupportSrc, '.DS_Store'), '');
+
+    await expect(installCommand(makeOptions({ harness: 'claude' }), tempDir, contentDir)).resolves.toBeUndefined();
+
+    expect(existsSync(path.join(claudeHome, 'skills', 'empty-support'))).toBe(false);
+    const manifest = await readManifest(getManifestPath(tempDir));
+    const entries = manifest.harnesses.claude?.entries ?? [];
+    expect(entries.some((entry) => entry.relativePath === 'skills/empty-support')).toBe(false);
+  });
+
   it('writes nothing in dry-run mode', async () => {
     const claudeHome = await setupClaudeHome();
 
diff --git a/packages/agents/src/commands/install.ts b/packages/agents/src/commands/install.ts
index 7ea6462c..c632c28d 100644
--- a/packages/agents/src/commands/install.ts
+++ b/packages/agents/src/commands/install.ts
@@ -209,7 +209,9 @@ async function installSkills(
       contentDir,
       toolMapping,
     );
-    entries.push(result);
+    if (result !== undefined) {
+      entries.push(result);
+    }
   }
 
   // Install harness-specific skills from _harnesses/{harnessId}/
@@ -244,7 +246,9 @@ async function installSkills(
       toolMapping,
       '(harness-specific)',
     );
-    entries.push(result);
+    if (result !== undefined) {
+      entries.push(result);
+    }
   }
 
   return entries;
@@ -286,7 +290,7 @@ async function installSkillEntry(
   contentDir: string,
   toolMapping: ReadonlyMap<string, string>,
   label = '',
-): Promise<ManifestEntry> {
+): Promise<ManifestEntry | undefined> {
   // Eagerly render the skill's final body before the dry-run gate, so missing include targets, cycles, out-of-tree
   // references, and unmapped tool placeholders surface even when no files are written. Directory entries render the
   // whole tree (include expansion, tool-name + link/template rewriting) into the exact bytes the write phase emits;
@@ -307,6 +311,13 @@ async function installSkillEntry(
     expandedFileContent = rewriteToolNames(expanded, toolMapping, relativeFromContent(contentDir, srcPath));
   }
 
+  // A support directory holding only dotfiles or `_partials/` renders to zero entries — nothing to install. Skip it
+  // entirely: no destination, no markers, no manifest entry. The orphan-prune pass clears any previously installed copy.
+  if (renderedDir !== undefined && renderedDir.length === 0) {
+    console.info(`    [skip] ${relativePath}${label ? ` ${label}` : ''} (no installable entries)`);
+    return undefined;
+  }
+
   if (options.dryRun) {
     console.info(`    [copy] ${relativePath}${label ? ` ${label}` : ''}`);
     return { relativePath, contentHash: 'dry-run', linked: false };