Lint cleanup sweep: 591 -> 95 errors (ar-r82f.14) (#95)

* Lint cleanup sweep: 591 -> 95 errors

Cosmetic-only sweep on IABTechLab/buyer-agent. No behavior changes.

Categories fixed (auto-fix + manual):
- I001 (72) imports unsorted -- auto-fix
- UP045 (112) Optional[X] -> X | None -- auto-fix
- UP017 (25) datetime.timezone.utc -> datetime.UTC -- auto-fix
- UP006 (14), UP035 (10), UP037 (2), UP041 (1), UP012 (1) -- auto-fix
- F541 (11), F401 (66 of 70) unused imports / f-strings -- auto-fix +
  noqa for 3 intentional availability-probe imports in examples
- E501 (117) long lines -- per-line noqa for code; file-level
  '# ruff: noqa: E501' for 5 files where overlong lines sit inside
  string literals / docstrings and cannot be wrapped without changing
  output formatting
- F841 (17) unused local vars -- prefixed with '_' to mark intentional
- E402 (19) import-not-at-top -- noqa where imports legitimately follow
  dotenv load / mounting / lazy guards
- E722 (2), E731 (1), F811 (1) -- noqa (semantic change to fix)
- F821 (1) Undefined `Optional` after auto-fix removed the import in
  tests/unit/test_deal_store.py -- restored intent with `DealStore | None`

Categories deferred:
- N806 (49) variable should be lowercase -- renaming is behavior-adjacent
- UP042 (36) replace Enum with StrEnum -- requires --unsafe-fixes
- N818 (4), N817 (4), N814 (2) exception / import naming -- behavior-adjacent
- E741 was eliminated via file-level noqa in examples/buyer_demo.py
  (single-char 'l' used as line iteration variable)

Tests: 3225 passed, 4 skipped, 0 failed (full unit + integration suite).
No regressions; identical pass/fail mix to base commit 90764ab.

bead: ar-r82f.14

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

* Configure ruff to ignore deferred lint categories

After the cosmetic sweep cleared 496 of 591 errors, the remaining 95 fall
into categories the sweep explicitly deferred:

- N806 (49): variable should be lowercase -- renaming is behavior-adjacent
- UP042 (36): replace Enum with StrEnum -- requires --unsafe-fixes
- N818 (4), N817 (4), N814 (2): naming -- behavior-adjacent

Adding these to `tool.ruff.lint.ignore` documents the deferral and lets CI
`ruff check src/ tests/` pass cleanly. Each entry has a comment explaining
why it is deferred so the next cleanup pass knows the rationale.

Note: `ruff format --check` was already failing on main (80 files) and is
unrelated to this sweep -- a follow-up bead should run `ruff format` after
this lands.

bead: ar-r82f.14

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: atc964

.beads/generate_progress.py

@@ -14,7 +14,7 @@
 import re
 import shutil
 import subprocess
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from pathlib import Path
 
 BEADS_DIR = Path(__file__).parent
@@ -496,7 +496,7 @@ def generate():
 
     # Discover epics and build phase structure
     epics = discover_epics(issues)
-    epic_ids = set(epics.keys())
+    _epic_ids = set(epics.keys())
 
     # Also exclude non-phase epics from display (e.g. "Epic: Buyer reporting agent")
     all_epic_ids = {i["id"] for i in issues if i.get("issue_type") == "epic"}
@@ -611,7 +611,7 @@ def generate():
             lines.append(render_issue_row(issue, closed_ids, all_ids))
         lines.append("")
 
-    now = datetime.now(timezone.utc).strftime("%Y-%m-%d %H:%M UTC")
+    now = datetime.now(UTC).strftime("%Y-%m-%d %H:%M UTC")
     lines.append("---")
     lines.append(f"*Last updated: {now} — auto-generated by beads*\n")
 

.beads/test_generate_progress.py

@@ -14,7 +14,6 @@
 sys.path.insert(0, str(Path(__file__).parent))
 import generate_progress as gp
 
-
 # ---------------------------------------------------------------------------
 # Fixtures: synthetic issue data
 # ---------------------------------------------------------------------------
@@ -467,7 +466,6 @@ def test_full_generate_with_real_data(self):
 
             # No bead appears twice (check the ID column specifically)
             # Table format: | icon | ID | Task | ... — ID is in column index 2
-            import re
             bead_ids = []
             for line in content.split("\n"):
                 if not line.startswith("|") or "buyer-" not in line:

examples/basic_mcp_usage.py

@@ -12,7 +12,8 @@
 """
 
 import asyncio
-from ad_buyer.clients import UnifiedClient, Protocol
+
+from ad_buyer.clients import Protocol, UnifiedClient
 
 
 async def main():

examples/buyer_demo.py

@@ -102,7 +102,7 @@ async def demo_dsp_workflow():
         preferred_deal_types=[DealType.PREFERRED_DEAL],
     )
 
-    print(f"\nBuyer Identity:")
+    print("\nBuyer Identity:")
     print(f"  Agency: {identity.agency_name} ({identity.agency_holding_company})")
     print(f"  Advertiser: {identity.advertiser_name}")
     print(f"  Access Tier: {buyer_context.get_access_tier().value}")

examples/dsp_deal_discovery.py

@@ -12,7 +12,8 @@
 """
 
 import asyncio
-from ad_buyer.clients import IABMCPClient, A2AClient
+
+from ad_buyer.clients import A2AClient, IABMCPClient
 
 
 async def mcp_example():

examples/individual_clients.py

@@ -12,7 +12,8 @@
 """
 
 import asyncio
-from ad_buyer.clients import UnifiedClient, Protocol
+
+from ad_buyer.clients import Protocol, UnifiedClient
 
 
 async def main():

examples/natural_language_a2a.py

@@ -21,13 +21,12 @@
 
 import asyncio
 import os
-import signal
 import subprocess
 import sys
 import tempfile
 import time
+from datetime import UTC
 from pathlib import Path
-from typing import Optional
 
 # ---------------------------------------------------------------------------
 # Paths
@@ -175,7 +174,7 @@ def stop_server(proc: subprocess.Popen) -> None:
 # Results tracking
 # ---------------------------------------------------------------------------
 
-results: dict[str, Optional[bool]] = {
+results: dict[str, bool | None] = {
     "Auth": None,
     "Identity": None,
     "Registry": None,
@@ -332,7 +331,7 @@ def test_registry() -> bool:
     banner("[3/6] REGISTRY MODULE (client + cache)")
 
     from ad_buyer.registry.client import RegistryClient
-    from ad_buyer.registry.models import AgentCard, AgentCapability
+    from ad_buyer.registry.models import AgentCapability, AgentCard
 
     step("Create registry client")
     client = RegistryClient(
@@ -344,7 +343,7 @@ def test_registry() -> bool:
 
     step("Fetch agent card from seller (GET /.well-known/agent.json)")
 
-    async def _fetch_card() -> Optional[AgentCard]:
+    async def _fetch_card() -> AgentCard | None:
         return await client.fetch_agent_card(SELLER_URL)
 
     card = asyncio.run(_fetch_card())
@@ -400,7 +399,7 @@ async def _run_media_kit_tests() -> bool:
                 ok(f"Media kit: {kit.seller_name}, {kit.total_packages} packages")
             except MediaKitError as e:
                 if e.status_code == 404:
-                    warn(f"Seller does not have /media-kit endpoint (404)")
+                    warn("Seller does not have /media-kit endpoint (404)")
                     warn("Skipping remaining media kit tests")
                     return True  # Graceful skip
                 raise
@@ -465,11 +464,12 @@ async def _run_session_tests() -> bool:
             warn("Seller may not support /sessions endpoint")
             # Still test local persistence
             step("Testing local session store persistence")
+            from datetime import datetime, timedelta
+
             from ad_buyer.sessions.session_store import SessionRecord, SessionStore
-            from datetime import datetime, timedelta, timezone
 
             store = SessionStore(store_path)
-            now = datetime.now(timezone.utc)
+            now = datetime.now(UTC)
             record = SessionRecord(
                 session_id="local-test-001",
                 seller_url=SELLER_URL,
@@ -665,14 +665,14 @@ def main() -> int:
     # Pre-flight checks
     if not SELLER_VENV_PYTHON.exists():
         fail(f"Seller venv not found at {SELLER_VENV_PYTHON}")
-        fail("Run: cd ad_seller_system && python3.13 -m venv venv && source venv/bin/activate && pip install -e .")
+        fail("Run: cd ad_seller_system && python3.13 -m venv venv && source venv/bin/activate && pip install -e .")  # noqa: E501
         return 1
 
     # Create temp directory for test artifacts
     tmp_dir_obj = tempfile.mkdtemp(prefix="phase1_uat_")
     tmp_dir = tmp_dir_obj
 
-    server_proc: Optional[subprocess.Popen] = None
+    server_proc: subprocess.Popen | None = None
 
     try:
         # Start seller server

examples/phase1_uat.py

@@ -12,7 +12,8 @@
 """
 
 import asyncio
-from ad_buyer.clients import UnifiedClient, Protocol
+
+from ad_buyer.clients import Protocol, UnifiedClient
 
 
 async def main():

examples/protocol_switching.py

@@ -64,6 +64,15 @@ target-version = "py311"
 
 [tool.ruff.lint]
 select = ["E", "F", "I", "N", "W", "UP"]
+# Deferred categories — behavior-adjacent or require --unsafe-fixes.
+# Tracked separately for future cleanup; see bead ar-r82f.14 for context.
+ignore = [
+    "N806",  # variable in function should be lowercase (rename = behavior-adjacent)
+    "N814",  # camelcase import as constant (rename = behavior-adjacent)
+    "N817",  # camelcase import alias (rename = behavior-adjacent)
+    "N818",  # exception name should end with `Error` (rename = behavior-adjacent)
+    "UP042", # replace Enum with StrEnum (requires --unsafe-fixes, alters repr)
+]
 
 [tool.mypy]
 python_version = "3.11"