diff --git a/environments/benchmarks/terminalbench_2/terminalbench2_env.py b/environments/benchmarks/terminalbench_2/terminalbench2_env.py
index 7742059768a..1a76b8da61e 100644
--- a/environments/benchmarks/terminalbench_2/terminalbench2_env.py
+++ b/environments/benchmarks/terminalbench_2/terminalbench2_env.py
@@ -919,7 +919,7 @@ class TerminalBench2EvalEnv(HermesAgentBaseEnv):
             eval_metrics[f"eval/pass_rate_{cat_key}"] = cat_pass_rate
 
         # Store metrics for wandb_log
-        self.eval_metrics = [(k, v) for k, v in eval_metrics.items()]
+        self.eval_metrics = list(eval_metrics.items())
 
         # ---- Print summary ----
         print(f"\n{'='*60}")
diff --git a/environments/benchmarks/yc_bench/yc_bench_env.py b/environments/benchmarks/yc_bench/yc_bench_env.py
index 4fd22495440..6e7be2c899b 100644
--- a/environments/benchmarks/yc_bench/yc_bench_env.py
+++ b/environments/benchmarks/yc_bench/yc_bench_env.py
@@ -759,7 +759,7 @@ class YCBenchEvalEnv(HermesAgentBaseEnv):
             eval_metrics[f"eval/survival_rate_{key}"] = ps / pt if pt else 0
             eval_metrics[f"eval/avg_score_{key}"] = pa
 
-        self.eval_metrics = [(k, v) for k, v in eval_metrics.items()]
+        self.eval_metrics = list(eval_metrics.items())
 
         # --- Print summary ---
         print(f"\n{'='*60}")
diff --git a/gateway/platforms/discord.py b/gateway/platforms/discord.py
index a96e97815c8..5113f49f179 100644
--- a/gateway/platforms/discord.py
+++ b/gateway/platforms/discord.py
@@ -3724,7 +3724,7 @@ class DiscordAdapter(BasePlatformAdapter):
             return None
 
         # DMs, voice channels, and existing threads can't host child threads.
-        if isinstance(parent, getattr(discord, "DMChannel", tuple())):
+        if isinstance(parent, getattr(discord, "DMChannel", ())):
             logger.info(
                 "[%s] Handoff thread: parent %s is a DM; threads not supported here",
                 self.name, parent_chat_id,
diff --git a/gateway/platforms/feishu.py b/gateway/platforms/feishu.py
index 6d8222692db..ae3f7075104 100644
--- a/gateway/platforms/feishu.py
+++ b/gateway/platforms/feishu.py
@@ -1428,8 +1428,8 @@ class FeishuAdapter(BasePlatformAdapter):
                     per_chat_require_mention = _to_boolean(rule_cfg.get("require_mention"))
                 group_rules[str(chat_id)] = FeishuGroupRule(
                     policy=str(rule_cfg.get("policy", "open")).strip().lower(),
-                    allowlist=set(str(u).strip() for u in rule_cfg.get("allowlist", []) if str(u).strip()),
-                    blacklist=set(str(u).strip() for u in rule_cfg.get("blacklist", []) if str(u).strip()),
+                    allowlist={str(u).strip() for u in rule_cfg.get("allowlist", []) if str(u).strip()},
+                    blacklist={str(u).strip() for u in rule_cfg.get("blacklist", []) if str(u).strip()},
                     require_mention=per_chat_require_mention,
                 )
 
diff --git a/gateway/platforms/feishu_comment_rules.py b/gateway/platforms/feishu_comment_rules.py
index 054ef956989..25927bafb0a 100644
--- a/gateway/platforms/feishu_comment_rules.py
+++ b/gateway/platforms/feishu_comment_rules.py
@@ -228,7 +228,7 @@ def _load_pairing_approved() -> set:
     if isinstance(approved, dict):
         return set(approved.keys())
     if isinstance(approved, list):
-        return set(str(u) for u in approved if u)
+        return {str(u) for u in approved if u}
     return set()
 
 
diff --git a/gateway/platforms/telegram_network.py b/gateway/platforms/telegram_network.py
index 8fe4c280934..2975c6f029c 100644
--- a/gateway/platforms/telegram_network.py
+++ b/gateway/platforms/telegram_network.py
@@ -59,7 +59,7 @@ class TelegramFallbackTransport(httpx.AsyncBaseTransport):
     """
 
     def __init__(self, fallback_ips: Iterable[str], **transport_kwargs):
-        self._fallback_ips = [ip for ip in dict.fromkeys(_normalize_fallback_ips(fallback_ips))]
+        self._fallback_ips = list(dict.fromkeys(_normalize_fallback_ips(fallback_ips)))
         proxy_url = _resolve_proxy_url(target_hosts=[_TELEGRAM_API_HOST, *self._fallback_ips])
         if proxy_url and "proxy" not in transport_kwargs:
             transport_kwargs["proxy"] = proxy_url
diff --git a/hermes_state.py b/hermes_state.py
index 494ab3b2e7a..adbdff19ac9 100644
--- a/hermes_state.py
+++ b/hermes_state.py
@@ -2337,7 +2337,7 @@ class SessionDB:
                     "SELECT id FROM sessions WHERE started_at < ? AND ended_at IS NOT NULL",
                     (cutoff,),
                 )
-            session_ids = set(row["id"] for row in cursor.fetchall())
+            session_ids = {row["id"] for row in cursor.fetchall()}
 
             if not session_ids:
                 return 0
diff --git a/scripts/profile-tui.py b/scripts/profile-tui.py
index 13ce21fb3fc..6006eb09660 100755
--- a/scripts/profile-tui.py
+++ b/scripts/profile-tui.py
@@ -343,7 +343,7 @@ def key_metrics(data: dict[str, Any]) -> dict[str, float]:
         metrics["backpressure_frames"] = bp
 
     if react:
-        for pid in set(e["id"] for e in react):
+        for pid in {e["id"] for e in react}:
             ms = [e["actualMs"] for e in react if e["id"] == pid]
             metrics[f"react_{pid}_p99"] = pct(ms, 0.99)
             metrics[f"react_{pid}_max"] = max(ms)
diff --git a/scripts/release.py b/scripts/release.py
index 1c8377ff199..3aa30ea66ed 100755
--- a/scripts/release.py
+++ b/scripts/release.py
@@ -1426,7 +1426,7 @@ def main():
     print(f"  SemVer:          v{current_version} → v{new_version}")
     print(f"  Previous tag:    {prev_tag or '(none — first release)'}")
     print(f"  Commits:         {len(commits)}")
-    print(f"  Unique authors:  {len(set(c['github_author'] for c in commits))}")
+    print(f"  Unique authors:  {len({c['github_author'] for c in commits})}")
     print(f"  Mode:            {'PUBLISH' if args.publish else 'DRY RUN'}")
     print(f"{'='*60}")
     print()
diff --git a/tools/memory_tool.py b/tools/memory_tool.py
index 37f9cd4a715..236760a464a 100644
--- a/tools/memory_tool.py
+++ b/tools/memory_tool.py
@@ -291,7 +291,7 @@ class MemoryStore:
 
             if len(matches) > 1:
                 # If all matches are identical (exact duplicates), operate on the first one
-                unique_texts = set(e for _, e in matches)
+                unique_texts = {e for _, e in matches}
                 if len(unique_texts) > 1:
                     previews = [e[:80] + ("..." if len(e) > 80 else "") for _, e in matches]
                     return {
@@ -341,7 +341,7 @@ class MemoryStore:
 
             if len(matches) > 1:
                 # If all matches are identical (exact duplicates), remove the first one
-                unique_texts = set(e for _, e in matches)
+                unique_texts = {e for _, e in matches}
                 if len(unique_texts) > 1:
                     previews = [e[:80] + ("..." if len(e) > 80 else "") for _, e in matches]
                     return {
diff --git a/tools/mixture_of_agents_tool.py b/tools/mixture_of_agents_tool.py
index a34e99aa8f7..35f9fc003f0 100644
--- a/tools/mixture_of_agents_tool.py
+++ b/tools/mixture_of_agents_tool.py
@@ -54,6 +54,7 @@ from typing import Dict, Any, List, Optional
 from tools.openrouter_client import get_async_client as _get_openrouter_client, check_api_key as check_openrouter_api_key
 from agent.auxiliary_client import extract_content_or_reasoning
 from tools.debug_helpers import DebugSession
+import sys
 
 logger = logging.getLogger(__name__)
 
@@ -451,7 +452,7 @@ if __name__ == "__main__":
         print("❌ OPENROUTER_API_KEY environment variable not set")
         print("Please set your API key: export OPENROUTER_API_KEY='your-key-here'")
         print("Get API key at: https://openrouter.ai/")
-        exit(1)
+        sys.exit(1)
     else:
         print("✅ OpenRouter API key found")
     
diff --git a/tools/skills_guard.py b/tools/skills_guard.py
index 46503a7eb15..363e983da1a 100644
--- a/tools/skills_guard.py
+++ b/tools/skills_guard.py
@@ -928,5 +928,5 @@ def _build_summary(name: str, source: str, trust: str, verdict: str, findings: L
     if not findings:
         return f"{name}: clean scan, no threats detected"
 
-    categories = set(f.category for f in findings)
+    categories = {f.category for f in findings}
     return f"{name}: {verdict} — {len(findings)} finding(s) in {', '.join(sorted(categories))}"
diff --git a/tools/skills_sync.py b/tools/skills_sync.py
index 98cd85c3940..0c65b6281c7 100644
--- a/tools/skills_sync.py
+++ b/tools/skills_sync.py
@@ -345,7 +345,7 @@ def reset_bundled_skill(name: str, restore: bool = False) -> dict:
     manifest = _read_manifest()
     bundled_dir = _get_bundled_dir()
     bundled_skills = _discover_bundled_skills(bundled_dir)
-    bundled_by_name = {skill_name: skill_dir for skill_name, skill_dir in bundled_skills}
+    bundled_by_name = dict(bundled_skills)
 
     in_manifest = name in manifest
     is_bundled = name in bundled_by_name
diff --git a/tools/skills_tool.py b/tools/skills_tool.py
index 5d219771791..32296729fe2 100644
--- a/tools/skills_tool.py
+++ b/tools/skills_tool.py
@@ -721,7 +721,7 @@ def skills_list(category: str = None, task_id: str = None) -> str:
 
         # Extract unique categories
         categories = sorted(
-            set(s.get("category") for s in all_skills if s.get("category"))
+            {s.get("category") for s in all_skills if s.get("category")}
         )
 
         return json.dumps(
diff --git a/tools/terminal_tool.py b/tools/terminal_tool.py
index 57bc42b2a22..4d8512c345e 100644
--- a/tools/terminal_tool.py
+++ b/tools/terminal_tool.py
@@ -888,6 +888,7 @@ from tools.environments.docker import DockerEnvironment as _DockerEnvironment
 from tools.environments.modal import ModalEnvironment as _ModalEnvironment
 from tools.environments.managed_modal import ManagedModalEnvironment as _ManagedModalEnvironment
 from tools.managed_tool_gateway import is_managed_tool_gateway_ready
+import sys
 
 
 # Tool description for LLM
@@ -2243,7 +2244,7 @@ if __name__ == "__main__":
 
     if not check_terminal_requirements():
         print("\n❌ Requirements not met. Please check the messages above.")
-        exit(1)
+        sys.exit(1)
 
     print("\n✅ All requirements met!")
     print("\nAvailable Tool:")
diff --git a/tools/tts_tool.py b/tools/tts_tool.py
index 8c32d66de18..95958fd1833 100644
--- a/tools/tts_tool.py
+++ b/tools/tts_tool.py
@@ -848,13 +848,13 @@ def _generate_openai_tts(text: str, output_path: str, tts_config: Dict[str, Any]
     OpenAIClient = _import_openai_client()
     client = OpenAIClient(api_key=api_key, base_url=base_url)
     try:
-        create_kwargs = dict(
-            model=model,
-            voice=voice,
-            input=text,
-            response_format=response_format,
-            extra_headers={"x-idempotency-key": str(uuid.uuid4())},
-        )
+        create_kwargs = {
+            "model": model,
+            "voice": voice,
+            "input": text,
+            "response_format": response_format,
+            "extra_headers": {"x-idempotency-key": str(uuid.uuid4())},
+        }
         if speed != 1.0:
             create_kwargs["speed"] = max(0.25, min(4.0, speed))
         response = client.audio.speech.create(**create_kwargs)
diff --git a/tools/vision_tools.py b/tools/vision_tools.py
index 96401294748..912777e2e25 100644
--- a/tools/vision_tools.py
+++ b/tools/vision_tools.py
@@ -41,6 +41,7 @@ from agent.auxiliary_client import async_call_llm, extract_content_or_reasoning
 from hermes_constants import get_hermes_dir
 from tools.debug_helpers import DebugSession
 from tools.website_policy import check_website_access
+import sys
 
 logger = logging.getLogger(__name__)
 
@@ -937,7 +938,7 @@ if __name__ == "__main__":
     if not api_available:
         print("❌ No auxiliary vision model available")
         print("Configure a supported multimodal backend (OpenRouter, Nous, Codex, Anthropic, or a custom OpenAI-compatible endpoint).")
-        exit(1)
+        sys.exit(1)
     else:
         print("✅ Vision model available")
     
diff --git a/tools/web_tools.py b/tools/web_tools.py
index df16c31db78..ba14b07a41c 100644
--- a/tools/web_tools.py
+++ b/tools/web_tools.py
@@ -100,6 +100,7 @@ from tools.managed_tool_gateway import (
 from tools.tool_backend_helpers import managed_nous_tools_enabled, prefers_gateway
 from tools.url_safety import is_safe_url
 from tools.website_policy import check_website_access
+import sys
 
 logger = logging.getLogger(__name__)
 
@@ -2153,7 +2154,7 @@ if __name__ == "__main__":
         print(f"✅ Auxiliary model available: {default_summarizer_model}")
 
     if not web_available:
-        exit(1)
+        sys.exit(1)
 
     print("🛠️  Web tools ready for use!")
     
diff --git a/tui_gateway/server.py b/tui_gateway/server.py
index 6635a5cda3c..d105250701d 100644
--- a/tui_gateway/server.py
+++ b/tui_gateway/server.py
@@ -1624,27 +1624,27 @@ def _on_tool_progress(
 
 
 def _agent_cbs(sid: str) -> dict:
-    return dict(
-        tool_start_callback=lambda tc_id, name, args: _on_tool_start(
+    return {
+        "tool_start_callback": lambda tc_id, name, args: _on_tool_start(
             sid, tc_id, name, args
         ),
-        tool_complete_callback=lambda tc_id, name, args, result: _on_tool_complete(
+        "tool_complete_callback": lambda tc_id, name, args, result: _on_tool_complete(
             sid, tc_id, name, args, result
         ),
-        tool_progress_callback=lambda event_type, name=None, preview=None, args=None, **kwargs: _on_tool_progress(
+        "tool_progress_callback": lambda event_type, name=None, preview=None, args=None, **kwargs: _on_tool_progress(
             sid, event_type, name, preview, args, **kwargs
         ),
-        tool_gen_callback=lambda name: _tool_progress_enabled(sid)
+        "tool_gen_callback": lambda name: _tool_progress_enabled(sid)
         and _emit("tool.generating", sid, {"name": name}),
-        thinking_callback=lambda text: _emit("thinking.delta", sid, {"text": text}),
-        reasoning_callback=lambda text: _emit("reasoning.delta", sid, {"text": text}),
-        status_callback=lambda kind, text=None: _status_update(
+        "thinking_callback": lambda text: _emit("thinking.delta", sid, {"text": text}),
+        "reasoning_callback": lambda text: _emit("reasoning.delta", sid, {"text": text}),
+        "status_callback": lambda kind, text=None: _status_update(
             sid, str(kind), None if text is None else str(text)
         ),
-        clarify_callback=lambda q, c: _block(
+        "clarify_callback": lambda q, c: _block(
             "clarify.request", sid, {"question": q, "choices": c}
         ),
-    )
+    }
 
 
 def _wire_callbacks(sid: str):