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+# Session snapshot — 2026-04-15
+
+**Branch:** main  
+**Commit:** f4ec8b1 — feat: implement AD backend aliases and fix identity shard async calls (#3)  
+**Status:** ✅ Committed and pushed to origin/main
+
+---
+
+## Session goals
+
+Resolve all 7 active Pylance diagnostics in the identity shard caused by
+call-site mismatches between identity.py and the AD adapter API, and validate
+the fixes against the existing unit test suite.
+
+---
+
+## Accomplishments
+
+- **Diagnosed 7 Pylance errors** across two error classes:
+  - `CoroutineType not assignable` — asyncio.to_thread wrapping async methods
+  - `Attribute unknown` — call sites referencing methods not on the adapter class
+
+- **Fixed async call semantics (identity.py)**
+  - Removed all `asyncio.to_thread()` wrappers around adapter async methods
+  - Replaced with direct `await _get_ad().<method>(...)` calls
+  - Resolved: `ad_get_user` (line 60), `ad_get_group_members` (line 120)
+
+- **Remapped missing method calls (identity.py)**
+  - `search_users` → `search_users_by_name` (method renamed in adapter)
+  - `get_stale_accounts` → `find_stale_users` (method renamed in adapter)
+  - `get_disabled_accounts` → `query_users(filter_params={"enabled": False})`
+  - `get_user_by_email` → bounded `query_users` page scan + in-memory email match
+  - `get_groups` → temporary empty-list fallback + `logger.warning` + WIS-018 TODO
+
+- **Preserved tool contracts** — `ad_get_group_members` keeps `list[dict]` return type;
+  backend `list[str]` usernames are wrapped as `{"sAMAccountName": u}` objects
+
+- **Added structured logging** — `import logging` + `logger = logging.getLogger(__name__)`
+  added to identity shard; warning emitted when unimplemented group listing is called
+
+- **Verified: 0 Pylance diagnostics** — confirmed via VS Code language server
+- **Verified: 19/19 unit tests passing** — `tests/identity_tests/test_ad_adapter.py`
+
+- **Live tool validation (mock mode)**
+  - `scan_status_reconciliation` — detected EMP002 (Taylor Brooks) terminated in
+    Workday but still enabled in AD
+  - `ad_get_disabled_accounts` — returned David Kim (EMP-1004, UAC 514)
+  - `nexus_audit_recent` — confirmed 13 clean READ-only audit entries, no errors
+
+---
+
+## Technical debt / pending
+
+| ID | Item | Priority |
+| :--- | :--- | :---: |
+| WIS-018 | Add `get_groups()` to `ActiveDirectoryIdentityBackend` to replace empty-list fallback in `ad_list_groups` | Medium |
+| — | `ad_get_user_by_email` uses a full paginated scan; add a dedicated AD `mail` filter method in the backend if directory size becomes a latency concern | Low |
+| — | `ADUserAdapter.to_canonical` reads raw LDAP field names (`sAMAccountName`, `mail`); the query_users email path returns normalized field names — field-name alignment between adapter and canonical transformer should be reviewed in a future pass | Low |
+
+---
+
+## Next steps
+
+1. **WIS-018 — Add `get_groups()` to ad_adapter.py**
+   - Use `Get-ADGroup -Filter *` with `Name`, `DistinguishedName`, `GroupCategory` properties
+   - Follow the existing `find_stale_users` pattern (PowerShell → JSON → normalized list)
+   - Add unit test in `tests/identity_tests/test_ad_adapter.py`
+   - Remove the temporary fallback + TODO from `ad_list_groups` in identity.py
+
+2. **Integration smoke test** — when a non-production AD is available, run
+   `pytest tests/identity_tests/test_integration.py -v` with `AD_TEST_USERNAME`
+   and `AD_TEST_PASSWORD` set
+
+3. **Field-name audit** — trace `query_users` output keys through `ADUserAdapter.to_canonical`
+   to confirm the email-scan path in `ad_get_user_by_email` produces a valid canonical object
+
+---
+
+## Environment
+
+- **Python:** `.venv` (nexus-mcp)
+- **Mock mode:** `USE_MOCK=true`
+- **MCP server:** `nexus` (stdio, src/main.py)
+- **Active shards:** identity, workday, audit, itsm, assets, logistics