diff --git a/src/langbot/pkg/api/http/service/skill.py b/src/langbot/pkg/api/http/service/skill.py
index 09e640d7..0b413fd7 100644
--- a/src/langbot/pkg/api/http/service/skill.py
+++ b/src/langbot/pkg/api/http/service/skill.py
@@ -21,7 +21,6 @@ _FRONTMATTER_FIELDS = (
     'name',
     'display_name',
     'description',
-    'auto_activate',
 )
 
 _PUBLIC_SKILL_FIELDS = (
@@ -30,7 +29,6 @@ _PUBLIC_SKILL_FIELDS = (
     'description',
     'instructions',
     'package_root',
-    'auto_activate',
     'created_at',
     'updated_at',
 )
@@ -51,8 +49,6 @@ def _build_skill_md(metadata: dict, instructions: str) -> str:
         value = metadata.get(key)
         if value is None:
             continue
-        if key == 'auto_activate' and value is True:
-            continue
         if isinstance(value, str) and not value.strip():
             continue
         frontmatter[key] = value
@@ -118,7 +114,6 @@ class SkillService:
             'name': name,
             'display_name': self._resolve_create_field(data, 'display_name', imported_skill_data, default=''),
             'description': self._resolve_create_field(data, 'description', imported_skill_data, default=''),
-            'auto_activate': self._resolve_create_bool(data, 'auto_activate', imported_skill_data, default=True),
         }
         instructions = self._resolve_create_field(data, 'instructions', imported_skill_data, default='')
         self._write_skill_md(target_root, metadata, instructions)
@@ -147,7 +142,6 @@ class SkillService:
             'name': skill['name'],
             'display_name': data.get('display_name', skill.get('display_name', '')),
             'description': data.get('description', skill.get('description', '')),
-            'auto_activate': data.get('auto_activate', skill.get('auto_activate', True)),
         }
         instructions = str(data.get('instructions', skill.get('instructions', '')) or '')
         self._write_skill_md(skill['package_root'], metadata, instructions)
@@ -372,7 +366,6 @@ class SkillService:
             'display_name': str(metadata.get('display_name') or '').strip(),
             'description': str(metadata.get('description') or '').strip(),
             'instructions': instructions,
-            'auto_activate': bool(metadata.get('auto_activate', True)),
         }
 
     async def _reload_skills(self) -> None:
@@ -400,7 +393,6 @@ class SkillService:
             'display_name': str(metadata.get('display_name') or '').strip(),
             'description': str(metadata.get('description') or '').strip(),
             'instructions': instructions,
-            'auto_activate': bool(metadata.get('auto_activate', True)),
         }
 
     async def _download_github_skill_to_temp(self, asset_url: str, tmp_dir: str) -> str:
@@ -488,7 +480,6 @@ class SkillService:
                     'display_name': str(metadata.get('display_name') or '').strip(),
                     'description': str(metadata.get('description') or '').strip(),
                     'instructions': instructions,
-                    'auto_activate': bool(metadata.get('auto_activate', True)),
                     'package_root': self._build_preview_target_dir(base_target_name, relative_path, suffix),
                 }
             )
@@ -626,14 +617,6 @@ class SkillService:
             return str(imported_skill_data.get(field, default) or default)
         return value
 
-    @staticmethod
-    def _resolve_create_bool(data: dict, field: str, imported_skill_data: dict | None, *, default: bool) -> bool:
-        if field in data and data[field] is not None:
-            return bool(data[field])
-        if imported_skill_data is not None:
-            return bool(imported_skill_data.get(field, default))
-        return default
-
     def _write_skill_md(self, package_root: str, metadata: dict, instructions: str) -> None:
         package_root = self._normalize_package_root(package_root)
         os.makedirs(package_root, exist_ok=True)
diff --git a/src/langbot/pkg/pipeline/preproc/preproc.py b/src/langbot/pkg/pipeline/preproc/preproc.py
index 5ff2add6..ab8d5bfe 100644
--- a/src/langbot/pkg/pipeline/preproc/preproc.py
+++ b/src/langbot/pkg/pipeline/preproc/preproc.py
@@ -275,7 +275,7 @@ class PreProcessor(stage.PipelineStage):
                     f'Skill index injected into system prompt: '
                     f'pipeline={query.pipeline_uuid} '
                     f'bound_skills={bound_skills or "all"} '
-                    f'available_skills=[{", ".join(s["name"] for s in self.ap.skill_mgr.skills.values() if s.get("auto_activate", True))}]'
+                    f'available_skills=[{", ".join(s["name"] for s in self.ap.skill_mgr.skills.values() if bound_skills is None or s["name"] in bound_skills)}]'
                 )
                 # Append skill instruction to the first system message
                 if query.prompt.messages and query.prompt.messages[0].role == 'system':
diff --git a/src/langbot/pkg/provider/tools/loaders/skill_authoring.py b/src/langbot/pkg/provider/tools/loaders/skill_authoring.py
index 9866a095..209979b9 100644
--- a/src/langbot/pkg/provider/tools/loaders/skill_authoring.py
+++ b/src/langbot/pkg/provider/tools/loaders/skill_authoring.py
@@ -105,7 +105,6 @@ class SkillAuthoringToolLoader(loader.ToolLoader):
                 'display_name': str(parameters.get('display_name', '') or '').strip(),
                 'description': str(parameters.get('description', '') or '').strip(),
                 'instructions': instructions,
-                'auto_activate': parameters.get('auto_activate', True),
             }
         )
         return {
@@ -137,7 +136,7 @@ class SkillAuthoringToolLoader(loader.ToolLoader):
             raise ValueError('name is required')
 
         data = {'name': name}
-        for field in ('display_name', 'description', 'instructions', 'auto_activate'):
+        for field in ('display_name', 'description', 'instructions'):
             if field in parameters:
                 data[field] = parameters[field]
 
@@ -172,7 +171,6 @@ class SkillAuthoringToolLoader(loader.ToolLoader):
                 'description': str(parameters.get('description') or scanned.get('description', '')).strip(),
                 'instructions': str(parameters.get('instructions') or scanned.get('instructions', '')),
                 'package_root': host_path,
-                'auto_activate': parameters.get('auto_activate', scanned.get('auto_activate', True)),
             }
         )
         return {
@@ -228,10 +226,6 @@ class SkillAuthoringToolLoader(loader.ToolLoader):
                         'type': 'string',
                         'description': 'The SKILL.md body instructions for the new skill.',
                     },
-                    'auto_activate': {
-                        'type': 'boolean',
-                        'description': 'Whether the skill should be considered for automatic activation. Defaults to true.',
-                    },
                 },
                 'required': ['name', 'instructions'],
                 'additionalProperties': False,
@@ -299,10 +293,6 @@ class SkillAuthoringToolLoader(loader.ToolLoader):
                         'type': 'string',
                         'description': 'Optional replacement SKILL.md body instructions.',
                     },
-                    'auto_activate': {
-                        'type': 'boolean',
-                        'description': 'Optional new auto_activate value.',
-                    },
                 },
                 'required': ['name'],
                 'additionalProperties': False,
@@ -363,10 +353,6 @@ class SkillAuthoringToolLoader(loader.ToolLoader):
                         'type': 'string',
                         'description': 'Optional instructions override.',
                     },
-                    'auto_activate': {
-                        'type': 'boolean',
-                        'description': 'Optional auto_activate override.',
-                    },
                 },
                 'required': ['path'],
                 'additionalProperties': False,
diff --git a/src/langbot/pkg/skill/activation.py b/src/langbot/pkg/skill/activation.py
index 6fd9fd93..4f142a0c 100644
--- a/src/langbot/pkg/skill/activation.py
+++ b/src/langbot/pkg/skill/activation.py
@@ -119,7 +119,12 @@ def prepare_skill_activation(
     if not response_content or not getattr(ap, 'skill_mgr', None):
         return None
 
-    activated_skill_names = ap.skill_mgr.detect_skill_activations(response_content)
+    visible_skills = skill_loader.get_visible_skills(ap, query)
+    activated_skill_names = [
+        skill_name
+        for skill_name in ap.skill_mgr.detect_skill_activations(response_content)
+        if skill_name in visible_skills
+    ]
     if not activated_skill_names:
         return None
 
diff --git a/src/langbot/pkg/skill/manager.py b/src/langbot/pkg/skill/manager.py
index bf8b48e4..d227fceb 100644
--- a/src/langbot/pkg/skill/manager.py
+++ b/src/langbot/pkg/skill/manager.py
@@ -135,7 +135,6 @@ class SkillManager:
                 'raw_content': content,
                 'package_root': package_root,
                 'entry_file': entry_file,
-                'auto_activate': bool(metadata.get('auto_activate', True)),
                 'created_at': dt.datetime.fromtimestamp(stat.st_ctime, tz=dt.timezone.utc).isoformat(),
                 'updated_at': dt.datetime.fromtimestamp(stat.st_mtime, tz=dt.timezone.utc).isoformat(),
             }
@@ -154,8 +153,6 @@ class SkillManager:
     def get_skill_index(self, pipeline_uuid: str | None = None, bound_skills: list[str] | None = None) -> str:
         skills_to_index = []
         for skill in self.skills.values():
-            if not skill.get('auto_activate', True):
-                continue
             if bound_skills is not None and skill['name'] not in bound_skills:
                 continue
             skills_to_index.append(skill)
diff --git a/tests/unit_tests/provider/test_skill_tools.py b/tests/unit_tests/provider/test_skill_tools.py
index dc7cd182..867d5dc1 100644
--- a/tests/unit_tests/provider/test_skill_tools.py
+++ b/tests/unit_tests/provider/test_skill_tools.py
@@ -22,7 +22,6 @@ def _make_skill_data(
     instructions='Do something',
     package_root='',
     entry_file='SKILL.md',
-    auto_activate=True,
     **kwargs,
 ):
     return {
@@ -32,7 +31,6 @@ def _make_skill_data(
         'instructions': instructions,
         'package_root': package_root,
         'entry_file': entry_file,
-        'auto_activate': auto_activate,
         **kwargs,
     }
 
@@ -150,6 +148,30 @@ class TestSkillActivationHelper:
         assert activation.cleaned_content == 'Working on it.'
         assert set(query.variables[ACTIVATED_SKILLS_KEY].keys()) == {'primary', 'aux'}
 
+    def test_prepare_skill_activation_ignores_skills_not_bound_to_pipeline(self):
+        from langbot.pkg.skill.activation import prepare_skill_activation
+        from langbot.pkg.provider.tools.loaders.skill import ACTIVATED_SKILLS_KEY, PIPELINE_BOUND_SKILLS_KEY
+        from langbot.pkg.skill.manager import SkillManager
+
+        ap = _make_ap()
+        mgr = SkillManager(ap)
+        mgr.skills = {
+            'primary': _make_skill_data(name='primary', instructions='Primary instructions'),
+            'hidden': _make_skill_data(name='hidden', instructions='Hidden instructions'),
+        }
+        ap.skill_mgr = mgr
+
+        query = SimpleNamespace(variables={PIPELINE_BOUND_SKILLS_KEY: ['primary']}, use_funcs=[])
+        activation = prepare_skill_activation(
+            ap,
+            query,
+            '[ACTIVATE_SKILL: hidden]\n[ACTIVATE_SKILL: primary]\nWorking on it.',
+        )
+
+        assert activation is not None
+        assert activation.activated_skill_names == ['primary']
+        assert set(query.variables[ACTIVATED_SKILLS_KEY].keys()) == {'primary'}
+
 
 class TestSkillPathHelpers:
     def test_get_visible_skills_filters_by_bound_names(self):
@@ -252,7 +274,6 @@ class TestSkillAuthoringToolLoader:
                 'display_name': 'Prompt Skill',
                 'description': 'Prompt only skill',
                 'instructions': 'Follow these steps carefully.',
-                'auto_activate': False,
             },
             SimpleNamespace(),
         )
@@ -263,7 +284,6 @@ class TestSkillAuthoringToolLoader:
                 'display_name': 'Prompt Skill',
                 'description': 'Prompt only skill',
                 'instructions': 'Follow these steps carefully.',
-                'auto_activate': False,
             }
         )
         assert result == {
@@ -342,7 +362,6 @@ class TestSkillAuthoringToolLoader:
                 'name': 'time-now',
                 'description': 'Fixed to Beijing time',
                 'instructions': 'Always use Asia/Shanghai and never offer other timezones.',
-                'auto_activate': True,
             },
             SimpleNamespace(),
         )
@@ -353,7 +372,6 @@ class TestSkillAuthoringToolLoader:
                 'name': 'time-now',
                 'description': 'Fixed to Beijing time',
                 'instructions': 'Always use Asia/Shanghai and never offer other timezones.',
-                'auto_activate': True,
             },
         )
         assert result == {
@@ -400,7 +418,6 @@ class TestSkillAuthoringToolLoader:
                     'display_name': 'Cloned Skill',
                     'description': 'Imported from clone',
                     'instructions': 'Do work',
-                    'auto_activate': True,
                 }
             ),
             create_skill=AsyncMock(return_value=_make_skill_data(name='cloned-skill', package_root='/repo/root')),
@@ -430,7 +447,6 @@ class TestSkillAuthoringToolLoader:
                 'description': 'Imported from clone',
                 'instructions': 'Do work',
                 'package_root': os.path.realpath(repo_dir),
-                'auto_activate': True,
             }
         )
         assert result['imported'] is True
diff --git a/tests/unit_tests/test_skill_service.py b/tests/unit_tests/test_skill_service.py
index acba02bd..178563f3 100644
--- a/tests/unit_tests/test_skill_service.py
+++ b/tests/unit_tests/test_skill_service.py
@@ -15,14 +15,11 @@ def _create_skill_file(
     name: str = 'imported-skill',
     display_name: str = '',
     description: str = 'Imported from local directory',
-    auto_activate: bool = True,
     body: str = 'Skill instructions',
 ) -> None:
     frontmatter = ['name: ' + name, 'description: ' + description]
     if display_name:
         frontmatter.insert(1, 'display_name: ' + display_name)
-    if not auto_activate:
-        frontmatter.append('auto_activate: false')
 
     path.write_text(
         '---\n' + '\n'.join(frontmatter) + f'\n---\n\n{body}\n',
@@ -83,7 +80,6 @@ async def test_create_skill_import_preserves_existing_skill_content_when_form_fi
         source_dir / 'SKILL.md',
         display_name='Imported Skill',
         description='Imported description',
-        auto_activate=False,
         body='Original instructions',
     )
 
@@ -96,7 +92,6 @@ async def test_create_skill_import_preserves_existing_skill_content_when_form_fi
             'package_root': str(managed_root.resolve()),
             'description': 'Imported description',
             'instructions': 'Original instructions',
-            'auto_activate': False,
         }
     )
 
@@ -115,7 +110,6 @@ async def test_create_skill_import_preserves_existing_skill_content_when_form_fi
     content = (managed_root / 'SKILL.md').read_text(encoding='utf-8')
     assert 'display_name: Imported Skill' in content
     assert 'description: Imported description' in content
-    assert 'auto_activate: false' in content
     assert content.endswith('Original instructions')
 
 
@@ -139,7 +133,6 @@ async def test_create_skill_reuses_existing_managed_directory_without_copying(tm
             'package_root': str(managed_root.resolve()),
             'description': 'Already managed',
             'instructions': 'Managed instructions',
-            'auto_activate': True,
         }
     )
 
@@ -167,11 +160,7 @@ def _build_skill_archive() -> bytes:
     with zipfile.ZipFile(stream, 'w') as archive:
         archive.writestr(
             'demo-repo-main/skills/nested-skill/SKILL.md',
-            '---\n'
-            'name: imported-skill\n'
-            'description: Imported from GitHub archive\n'
-            '---\n\n'
-            'Skill instructions\n',
+            '---\nname: imported-skill\ndescription: Imported from GitHub archive\n---\n\nSkill instructions\n',
         )
     return stream.getvalue()
 
@@ -336,7 +325,6 @@ async def test_update_skill_rejects_package_root_change(tmp_path):
             'display_name': 'Writer',
             'description': 'Writes things',
             'instructions': 'Do work',
-            'auto_activate': True,
         }
     )
 
diff --git a/web/src/app/home/skills/components/skill-form/SkillForm.tsx b/web/src/app/home/skills/components/skill-form/SkillForm.tsx
index 9db5d2c3..93b32171 100644
--- a/web/src/app/home/skills/components/skill-form/SkillForm.tsx
+++ b/web/src/app/home/skills/components/skill-form/SkillForm.tsx
@@ -3,7 +3,6 @@ import { useTranslation } from 'react-i18next';
 import { Input } from '@/components/ui/input';
 import { Label } from '@/components/ui/label';
 import { Textarea } from '@/components/ui/textarea';
-import { Switch } from '@/components/ui/switch';
 import { Button } from '@/components/ui/button';
 import { FolderSearch, ChevronDown, ChevronRight } from 'lucide-react';
 import { httpClient } from '@/app/infra/http/HttpClient';
@@ -30,7 +29,6 @@ const emptySkillDraft: SkillFormDraft = {
     description: '',
     instructions: '',
     package_root: '',
-    auto_activate: true,
   },
   showAdvanced: false,
 };
@@ -95,7 +93,6 @@ export default function SkillForm({
         description: prev.description || result.description,
         package_root: result.package_root,
         instructions: result.instructions,
-        auto_activate: result.auto_activate ?? true,
       }));
       toast.success(t('skills.scanSuccess'));
     } catch (error) {
@@ -123,7 +120,6 @@ export default function SkillForm({
       display_name: skill.display_name || '',
       description: skill.description || '',
       instructions: skill.instructions || '',
-      auto_activate: skill.auto_activate ?? true,
     };
 
     try {
@@ -203,23 +199,6 @@ export default function SkillForm({
         />
       </div>
 
-      <div className="flex items-start justify-between gap-4">
-        <div className="space-y-1">
-          <Label htmlFor="auto_activate">{t('skills.autoActivate')}</Label>
-          <p className="text-xs leading-relaxed text-muted-foreground">
-            {t('skills.autoActivateDescription')}
-          </p>
-        </div>
-        <Switch
-          id="auto_activate"
-          className="mt-0.5"
-          checked={skill.auto_activate ?? true}
-          onCheckedChange={(checked) =>
-            setSkill({ ...skill, auto_activate: checked })
-          }
-        />
-      </div>
-
       <div className="space-y-3">
         <button
           type="button"
diff --git a/web/src/app/infra/entities/api/index.ts b/web/src/app/infra/entities/api/index.ts
index 8bd95b2e..e40e66b4 100644
--- a/web/src/app/infra/entities/api/index.ts
+++ b/web/src/app/infra/entities/api/index.ts
@@ -590,7 +590,6 @@ export interface Skill {
   description: string;
   instructions?: string;
   package_root?: string;
-  auto_activate?: boolean;
   is_builtin?: boolean;
   created_at?: string;
   updated_at?: string;
diff --git a/web/src/app/infra/http/BackendClient.ts b/web/src/app/infra/http/BackendClient.ts
index ab39be07..ae997920 100644
--- a/web/src/app/infra/http/BackendClient.ts
+++ b/web/src/app/infra/http/BackendClient.ts
@@ -1269,7 +1269,6 @@ export class BackendClient extends BaseHttpClient {
     display_name?: string;
     description: string;
     instructions: string;
-    auto_activate?: boolean;
   }> {
     return this.get('/api/v1/skills/scan', { path });
   }
diff --git a/web/src/i18n/locales/en-US.ts b/web/src/i18n/locales/en-US.ts
index 2877c07c..4f46bbbd 100644
--- a/web/src/i18n/locales/en-US.ts
+++ b/web/src/i18n/locales/en-US.ts
@@ -1346,9 +1346,6 @@ const enUS = {
       'Used as the skill directory name. Only letters, numbers, hyphens and underscores.',
     skillDescription: 'Skill Description',
     skillInstructions: 'Instructions',
-    autoActivate: 'Auto Activate',
-    autoActivateDescription:
-      'When enabled, the Agent may match and activate this skill based on its description during conversations.',
     saveSuccess: 'Saved successfully',
     saveError: 'Save failed: ',
     createSuccess: 'Created successfully',
diff --git a/web/src/i18n/locales/zh-Hans.ts b/web/src/i18n/locales/zh-Hans.ts
index 1c6d4cd9..c0f5808d 100644
--- a/web/src/i18n/locales/zh-Hans.ts
+++ b/web/src/i18n/locales/zh-Hans.ts
@@ -1290,9 +1290,6 @@ const zhHans = {
     skillSlugHelp: '用作技能目录名，仅支持英文字母、数字、连字符和下划线。',
     skillDescription: '技能描述',
     skillInstructions: '指令内容',
-    autoActivate: '自动激活',
-    autoActivateDescription:
-      '开启后，Agent 会在对话中根据技能描述自动匹配并激活此技能。',
     saveSuccess: '保存成功',
     saveError: '保存失败：',
     createSuccess: '创建成功',
diff --git a/web/src/i18n/locales/zh-Hant.ts b/web/src/i18n/locales/zh-Hant.ts
index 6e06d6f3..cb997bf3 100644
--- a/web/src/i18n/locales/zh-Hant.ts
+++ b/web/src/i18n/locales/zh-Hant.ts
@@ -1360,9 +1360,6 @@ const zhHant = {
     skillSlugHelp: '用作技能目錄名，僅支援英文字母、數字、連字符和底線。',
     skillDescription: '技能描述',
     skillInstructions: '指令內容',
-    autoActivate: '自動啟用',
-    autoActivateDescription:
-      '開啟後，Agent 會在對話中根據技能描述自動匹配並啟用此技能。',
     saveSuccess: '儲存成功',
     saveError: '儲存失敗：',
     createSuccess: '創建成功',