squash some bugs

docs/wf_mcp_capability_sources.md

@@ -124,6 +124,17 @@ Each upstream MCP connection is a source, for example `everything.default` or
 Connection sources are the only sources that represent upstream MCP server
 snapshots. System sources are local broker capabilities.
 
+A configured connection should still appear as a connection source even when no
+catalog snapshot has been loaded yet. In that state the source can have zero
+owned capabilities and a description such as `No catalog loaded for ...`; the
+absence of discovered capabilities must not make the configured connection
+disappear from source inventory.
+
+Connection discovery treats `tools/list` as the required workflow-facing family.
+Optional MCP families such as `resources/list` and `prompts/list` may be absent;
+servers that return MCP `Method not found` for those methods still refresh as
+tool-only sources instead of failing the whole catalog refresh.
+
 ## Projections
 
 ### Planner Catalog

src/wf_mcp/broker/discovery.py

@@ -1,17 +1,22 @@
 from __future__ import annotations
 
-from collections.abc import Callable
+from collections.abc import Awaitable, Callable
 from dataclasses import dataclass, field
-from typing import Any
+from typing import Any, TypeVar
+
+from mcp import McpError
+from mcp.types import METHOD_NOT_FOUND
 
 from wf_authoring import NodeSpec
 
 from ..capabilities import DiscoveredPrompt, DiscoveredResource, DiscoveredTool
 from ..models import AuthRecord, ConnectionConfig
 from ..sdk import BackendAdapter
+from ..shared import root_exception
 from ..workflow import wrap_discovered_tool
 from .events import McpEvent
 
+_CapabilityT = TypeVar("_CapabilityT")
 
 @dataclass(slots=True)
 class DiscoveredConnectionCapabilities:
@@ -28,8 +33,12 @@ async def discover_connection_capabilities(
     adapter: BackendAdapter,
 ) -> DiscoveredConnectionCapabilities:
     tools = await adapter.list_tools(connection, auth)
-    resources = await adapter.list_resources(connection, auth)
+    resources = await _list_optional_capabilities(
-    prompts = await adapter.list_prompts(connection, auth)
+        lambda: adapter.list_resources(connection, auth)
+    )
+    prompts = await _list_optional_capabilities(
+        lambda: adapter.list_prompts(connection, auth)
+    )
     metadata = await adapter.get_connection_metadata(connection, auth)
     return DiscoveredConnectionCapabilities(
         tools=tools,
@@ -39,6 +48,25 @@ async def discover_connection_capabilities(
     )
 
 
+async def _list_optional_capabilities(
+    load: Callable[[], Awaitable[list[_CapabilityT]]],
+) -> list[_CapabilityT]:
+    """Treat unsupported optional MCP capability families as empty lists.
+
+    Some SDK transports raise ``METHOD_NOT_FOUND`` from inside an
+    ``ExceptionGroup`` because the request ran through a task group. Resources
+    and prompts are optional families, so only that exact root error means "not
+    supported"; every other failure still needs to surface.
+    """
+    try:
+        return await load()
+    except Exception as exc:
+        root = root_exception(exc)
+        if isinstance(root, McpError) and root.error.code == METHOD_NOT_FOUND:
+            return []
+        raise
+
+
 def specs_from_discovered_tools(
     *,
     connection: ConnectionConfig,

src/wf_mcp/broker/service/core.py

@@ -644,18 +644,20 @@ class WfMcpService:
         self,
         connection: ConnectionConfig,
     ) -> None:
-        """Restore planner-visible connection specs from a stored catalog snapshot."""
+        """Register one connection source, hydrating specs from snapshot if present."""
         if connection.id in self.capability_sources:
             return
 
         snapshot = self.store.load_catalog(connection.id)
-        if snapshot is None or not snapshot.nodes:
-            return
-
         specs = {
             entry.qualified_name: self._spec_from_snapshot_entry(entry)
-            for entry in snapshot.nodes
+            for entry in (() if snapshot is None else snapshot.nodes)
         }
+        description = (
+            f"Specs restored from catalog for {connection.id}."
+            if specs
+            else f"No catalog loaded for {connection.id}."
+        )
         self.register_capability_source(
             CapabilitySource(
                 id=connection.id,
@@ -668,7 +670,7 @@ class WfMcpService:
                     admin_dashboard=True,
                 ),
                 permissions=SourcePermissions(calls_upstream=True),
-                description=f"Specs restored from catalog for {connection.id}.",
+                description=description,
             )
         )
 

tests/wf_mcp/test_sdk_adapter.py

@@ -3,7 +3,10 @@ from __future__ import annotations
 import asyncio
 
 import pytest
+from mcp import McpError
+from mcp.types import ErrorData
 
+from wf_mcp.capabilities import DiscoveredTool
 from wf_mcp.broker import WfMcpService
 from wf_mcp.models import ConnectionConfig
 from wf_mcp.sdk import McpSdkAdapter
@@ -17,6 +20,51 @@ from .test_support import (
 )
 
 
+class _ToolsOnlyAdapter:
+    async def list_tools(self, connection, auth):
+        return [
+            DiscoveredTool(
+                name="echo_tool",
+                title="Echo",
+                description="Echo text.",
+                input_schema={"type": "object", "properties": {}},
+                output_schema={"type": "object", "properties": {}},
+            )
+        ]
+
+    async def list_resources(self, connection, auth):
+        raise McpError(ErrorData(code=-32601, message="Method not found"))
+
+    async def list_prompts(self, connection, auth):
+        raise McpError(ErrorData(code=-32601, message="Method not found"))
+
+    async def get_connection_metadata(self, connection, auth):
+        return {"server": connection.server}
+
+    async def read_resource(self, connection, auth, uri):
+        raise NotImplementedError
+
+    async def get_prompt(self, connection, auth, prompt_name, arguments=None):
+        raise NotImplementedError
+
+    async def invoke_method(self, connection, auth, method, params=None):
+        raise NotImplementedError
+
+    async def send_notification(self, connection, auth, method, params=None):
+        raise NotImplementedError
+
+    async def call_tool(self, connection, auth, tool_name, payload):
+        raise NotImplementedError
+
+
+class _WrappedToolsOnlyAdapter(_ToolsOnlyAdapter):
+    async def list_resources(self, connection, auth):
+        raise ExceptionGroup(
+            "unhandled errors in a TaskGroup",
+            [McpError(ErrorData(code=-32601, message="Method not found"))],
+        )
+
+
 def test_mcp_sdk_adapter_lists_and_calls_stdio_tool() -> None:
     service = WfMcpService(store=FileStore(local_temp_root() / "sdk_adapter_store"))
     service.register_connection(
@@ -125,3 +173,45 @@ def test_mcp_sdk_adapter_can_probe_everything_server() -> None:
     )
     assert "resources" in payload
     assert "prompts" in payload
+
+
+def test_refresh_catalog_keeps_tools_when_optional_lists_are_unsupported() -> None:
+    service = WfMcpService(
+        store=FileStore(local_temp_root() / "tools_only_server_store")
+    )
+    service.register_connection(
+        ConnectionConfig(
+            id="tools_only.personal",
+            server="tools_only",
+            account="personal",
+        )
+    )
+    service.register_adapter("tools_only", _ToolsOnlyAdapter())
+
+    asyncio.run(service.refresh_connection_catalog("tools_only.personal"))
+
+    payload = service.get_catalog().as_payload()
+    assert payload["nodes"][0]["qualified_name"] == "tools_only.personal.echo_tool"
+    assert payload["resources"] == []
+    assert payload["prompts"] == []
+
+
+def test_refresh_catalog_unwraps_taskgroup_method_not_found() -> None:
+    service = WfMcpService(
+        store=FileStore(local_temp_root() / "wrapped_tools_only_server_store")
+    )
+    service.register_connection(
+        ConnectionConfig(
+            id="wrapped_tools_only.personal",
+            server="wrapped_tools_only",
+            account="personal",
+        )
+    )
+    service.register_adapter("wrapped_tools_only", _WrappedToolsOnlyAdapter())
+
+    asyncio.run(service.refresh_connection_catalog("wrapped_tools_only.personal"))
+
+    payload = service.get_catalog().as_payload()
+    assert payload["nodes"][0]["qualified_name"] == (
+        "wrapped_tools_only.personal.echo_tool"
+    )

tests/wf_mcp/test_service.py

@@ -103,6 +103,19 @@ def test_service_installs_builtin_stdlib_specs_by_default() -> None:
     )
 
 
+def test_service_registers_empty_source_for_connection_without_catalog() -> None:
+    service = WfMcpService(store=FileStore(local_temp_root() / "empty_source"))
+
+    service.register_connection(
+        ConnectionConfig(id="demo.personal", server="demo", account="personal")
+    )
+
+    source = service.capability_sources["demo.personal"]
+    assert source.enabled is True
+    assert source.capabilities.node_specs == {}
+    assert source.description == "No catalog loaded for demo.personal."
+
+
 def test_service_lists_all_capability_sources_with_owned_capability_names() -> None:
     service = WfMcpService(store=FileStore(local_temp_root() / "source_inventory"))