Made SkillCatalog's public surface minimal

Author: vijaydeepsinha

src/mcp/server/skills/catalog.py

@@ -109,13 +109,13 @@ def __init__(
         self,
         *,
         skills: Sequence[Skill],
-        files: Mapping[str, _SkillFileResource],
+        files: Mapping[str, Resource],
         directories: Mapping[str, Sequence[ResourceEntry]] | None,
         ttl_ms: int,
         cache_scope: Literal["public", "private"],
         page_size: int | None,
     ) -> None:
-        """Assemble a catalog from already-validated parts; use `SkillCatalog.load()` instead.
+        """Assemble a catalog from already-validated parts. Use `SkillCatalog.load()`, which builds them.
 
         Raises:
             ValidationError: If `ttl_ms` is negative.
@@ -232,11 +232,6 @@ async def load(
             page_size=page_size,
         )
 
-    @property
-    def skills(self) -> Sequence[Skill]:
-        """The valid skills, sorted by URI."""
-        return self._catalog_skills
-
     def resources(self) -> Sequence[ResourceBinding]:
         """One binding per served file, sorted by URI."""
         return [ResourceBinding(resource=file) for file in sorted(self._files.values(), key=lambda f: f.uri)]

tests/server/skills/test_catalog.py

@@ -42,6 +42,7 @@
     ReadDirectoryParams,
     ReadDirectoryRequest,
     ReadDirectoryResult,
+    Skill,
 )
 
 pytestmark = pytest.mark.anyio
@@ -88,6 +89,12 @@ def _digest(data: bytes) -> str:
     return f"sha256:{hashlib.sha256(data).hexdigest()}"
 
 
+async def _listed(catalog: SkillCatalog) -> list[Skill]:
+    server = MCPServer("skills", extensions=[catalog])
+    async with Client(server, extensions=[ClientSkills()]) as client:
+        return list(await client.extension(ClientSkills).list_skills())
+
+
 async def _server(files: Mapping[str, bytes], **options: Any) -> MCPServer:
     catalog = await SkillCatalog.load(_MemoryProvider(files), parse_frontmatter=_parse, **options)
     return MCPServer("skills", extensions=[catalog])
@@ -283,7 +290,7 @@ async def list_files(self) -> Sequence[str]:
     catalog = await SkillCatalog.load(
         GeneratorProvider({"git-workflow/SKILL.md": _skill_md("git-workflow")}), parse_frontmatter=_parse
     )
-    assert [skill.uri for skill in catalog.skills] == ["skill://git-workflow/SKILL.md"]
+    assert [skill.uri for skill in await _listed(catalog)] == ["skill://git-workflow/SKILL.md"]
 
 
 async def test_strict_load_raises_one_error_naming_every_invalid_skill() -> None:
@@ -345,7 +352,7 @@ def parse_with_date(text: str) -> Mapping[str, Any]:
     catalog = await SkillCatalog.load(
         _MemoryProvider({"git-workflow/SKILL.md": _skill_md("git-workflow")}), parse_frontmatter=parse_with_date
     )
-    assert catalog.skills[0].frontmatter == {
+    assert (await _listed(catalog))[0].frontmatter == {
         "name": "git-workflow",
         "description": "d",
         "released": "2026-07-28",
@@ -450,7 +457,7 @@ async def test_a_skill_over_the_recommended_limits_is_still_served_with_a_warnin
     with caplog.at_level(logging.WARNING, logger=CATALOG_LOGGER):
         catalog = await SkillCatalog.load(_MemoryProvider(files), parse_frontmatter=_parse)
 
-    assert [skill.uri for skill in catalog.skills] == ["skill://big/SKILL.md"]
+    assert [skill.uri for skill in await _listed(catalog)] == ["skill://big/SKILL.md"]
     assert len([record for record in caplog.records if "skill://big/SKILL.md" in record.getMessage()]) == 2