Addresses the four points raised in the automated review on PR #764:
1. Scope guards on the four search tools (search_files, find_by_name,
find_by_type, list_favorites) so an excluded `scope` raises ToolError
instead of silently returning an empty result. Previously an LLM
could probe the asymmetry between list_directory (raises) and the
search tools (silent) to infer that an excluded directory exists.
The 4 search tools now mirror the early-guard pattern from
list_directory and avoid an unnecessary upstream query for known-
excluded scopes.
2. Concurrent per-tag resolution in get_excluded_file_paths via
anyio.create_task_group(). Previously the 2N network calls (1
PROPFIND + 1 REPORT per tag) ran serially. Per-tag fail-open
behaviour is preserved by extracting _resolve_one_tag, which
swallows its own exceptions so a single tag failure does not abort
the surrounding task group.
3. WebDAVClient.get_tag_by_name and get_files_by_tag now route through
_make_request, inheriting the @retry_on_429 decorator. Previously
they bypassed it; with tag exclusion invoked on every WebDAV tool
call, a transient 429 from the systemtags endpoint was hitting the
fail-open path instead of being transparently retried.
4. Test coverage: 6 new tests in test_webdav_tools_exclusion.py (4
scope-guard, 2 missing filter tests for find_by_type and
list_favorites) and 2 new tests in test_tag_exclusion.py (a
concurrency proof using an event-barrier that would deadlock under
sequential execution, and a fail-open-under-task-group test with
order-independent side_effect callables).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
