feat: add file asset listing prompt

Expose list_file_assets so agents can browse allowed source files without relying on empty search queries.

Add a how_to_use_wiki_file_assets prompt to make the MCP purpose and workflow visible to clients that inspect prompts/resources before tools.

obsidian_wiki/mcp_server.py

@@ -151,6 +151,32 @@ def create_server(
             )
         )
 
+    @server.tool()
+    def list_file_assets(
+        doc_type: str | None = None,
+        source_type: str | None = None,
+        product_line: str | None = None,
+        customer: str | None = None,
+        competitor: str | None = None,
+        limit: int = 10,
+    ) -> list[dict[str, Any]]:
+        """List safe source files matching optional filters. Use search_file_assets when the user gives keywords such as product codes, sizes, or drawing names."""
+        return _as_mcp_results(
+            core_search_file_assets(
+                vault,
+                "",
+                db_path=db,
+                limit=limit,
+                doc_type=doc_type,
+                source_type=source_type,
+                product_line=product_line,
+                customer=customer,
+                competitor=competitor,
+                profile_name=profile_name,
+                expose_paths=expose_paths,
+            )
+        )
+
     @server.tool()
     def get_file_asset_metadata(file_id: str) -> dict[str, Any]:
         """Return safe metadata and the resource URI for one indexed source file."""
@@ -176,6 +202,22 @@ def create_server(
         )
         return resource["bytes"]
 
+    @server.prompt(
+        "how_to_use_wiki_file_assets",
+        description="Explain how to search and retrieve original source files from the wiki-file-assets MCP server.",
+    )
+    def how_to_use_wiki_file_assets() -> str:
+        return (
+            "wiki-file-assets serves original source files archived from an Obsidian wiki vault. "
+            "Use search_file_assets for keyword searches such as product codes, drawing names, sizes, "
+            "or document types. Use list_file_assets to browse allowed engineering files with optional "
+            "filters. Use get_file_asset_metadata with a file_id from search/list results to get the "
+            "asset://source/sha256/... URI, then read that resource to fetch the original file bytes. "
+            "This MCP is intentionally limited to safe engineering files such as drawings, CAD/3D models, "
+            "specifications, product parameters, and test reports; it blocks raw orders, prices, email "
+            "correspondence, complaint evidence, claims, and personal data."
+        )
+
     return server
 
 

tests/test_mcp_server_remote.py

@@ -100,12 +100,15 @@ class RemoteMcpServerTests(unittest.TestCase):
     def test_create_server_uses_file_asset_service_name(self):
         class FakeMCP:
             names = []
+            tool_names = []
+            prompt_names = []
 
             def __init__(self, name, **kwargs):
                 self.names.append(name)
 
             def tool(self):
                 def decorator(func):
+                    self.tool_names.append(func.__name__)
                     return func
 
                 return decorator
@@ -116,6 +119,13 @@ class RemoteMcpServerTests(unittest.TestCase):
 
                 return decorator
 
+            def prompt(self, name=None, **_kwargs):
+                def decorator(func):
+                    self.prompt_names.append(name or func.__name__)
+                    return func
+
+                return decorator
+
         with (
             tempfile.TemporaryDirectory() as tmp,
             patch.dict("sys.modules", {"mcp.server.fastmcp": type("Mod", (), {"FastMCP": FakeMCP})()}),
@@ -124,6 +134,10 @@ class RemoteMcpServerTests(unittest.TestCase):
 
         self.assertIsInstance(server, FakeMCP)
         self.assertEqual(FakeMCP.names[-1], "wiki-file-assets")
+        self.assertIn("search_file_assets", FakeMCP.tool_names)
+        self.assertIn("list_file_assets", FakeMCP.tool_names)
+        self.assertIn("get_file_asset_metadata", FakeMCP.tool_names)
+        self.assertIn("how_to_use_wiki_file_assets", FakeMCP.prompt_names)
 
     def test_run_http_server_fails_before_server_creation_without_token(self):
         with tempfile.TemporaryDirectory() as tmp: