diff --git a/src/config.py b/src/config.py
index f43be924..62b46809 100644
--- a/src/config.py
+++ b/src/config.py
@@ -87,8 +87,12 @@ class Settings(BaseSettings):
     xai_base_url: str = "https://api.x.ai/v1"
     grok_default_model: str = "grok-3-fast"
     grok_max_sats_per_query: int = 200
+    grok_sats_hard_cap: int = 100  # Absolute ceiling on sats per Grok query
     grok_free: bool = False  # Skip Lightning invoice when user has own API key
 
+    # ── Database ──────────────────────────────────────────────────────────
+    db_busy_timeout_ms: int = 5000  # SQLite PRAGMA busy_timeout (ms)
+
     # ── Claude (Anthropic) — cloud fallback backend ────────────────────────
     # Used when Ollama is offline and local inference isn't available.
     # Set ANTHROPIC_API_KEY to enable.  Default model is Haiku (fast + cheap).
diff --git a/src/timmy/memory/unified.py b/src/timmy/memory/unified.py
index 97fd888d..407c2754 100644
--- a/src/timmy/memory/unified.py
+++ b/src/timmy/memory/unified.py
@@ -14,6 +14,8 @@ from dataclasses import dataclass, field
 from datetime import UTC, datetime
 from pathlib import Path
 
+from config import settings
+
 logger = logging.getLogger(__name__)
 
 # Paths
@@ -28,7 +30,7 @@ def get_connection() -> Generator[sqlite3.Connection, None, None]:
     with closing(sqlite3.connect(str(DB_PATH))) as conn:
         conn.row_factory = sqlite3.Row
         conn.execute("PRAGMA journal_mode=WAL")
-        conn.execute("PRAGMA busy_timeout=5000")
+        conn.execute(f"PRAGMA busy_timeout={settings.db_busy_timeout_ms}")
         _ensure_schema(conn)
         yield conn
 
diff --git a/src/timmy/memory_system.py b/src/timmy/memory_system.py
index 76ddd5c3..c3d2d14c 100644
--- a/src/timmy/memory_system.py
+++ b/src/timmy/memory_system.py
@@ -20,6 +20,7 @@ from dataclasses import dataclass, field
 from datetime import UTC, datetime, timedelta
 from pathlib import Path
 
+from config import settings
 from timmy.memory.embeddings import (
     EMBEDDING_DIM,
     EMBEDDING_MODEL,  # noqa: F401 — re-exported for backward compatibility
@@ -111,7 +112,7 @@ def get_connection() -> Generator[sqlite3.Connection, None, None]:
     with closing(sqlite3.connect(str(DB_PATH))) as conn:
         conn.row_factory = sqlite3.Row
         conn.execute("PRAGMA journal_mode=WAL")
-        conn.execute("PRAGMA busy_timeout=5000")
+        conn.execute(f"PRAGMA busy_timeout={settings.db_busy_timeout_ms}")
         _ensure_schema(conn)
         yield conn
 
@@ -949,7 +950,7 @@ class SemanticMemory:
             with closing(sqlite3.connect(str(self.db_path))) as conn:
                 conn.row_factory = sqlite3.Row
                 conn.execute("PRAGMA journal_mode=WAL")
-                conn.execute("PRAGMA busy_timeout=5000")
+                conn.execute(f"PRAGMA busy_timeout={settings.db_busy_timeout_ms}")
                 # Ensure schema exists
                 conn.execute("""
                     CREATE TABLE IF NOT EXISTS memories (
diff --git a/src/timmy/tools.py b/src/timmy/tools.py
index 38ca74b1..37009092 100644
--- a/src/timmy/tools.py
+++ b/src/timmy/tools.py
@@ -24,6 +24,9 @@ from config import settings
 
 logger = logging.getLogger(__name__)
 
+# Max characters of user query included in Lightning invoice memo
+_INVOICE_MEMO_MAX_LEN = 50
+
 # Lazy imports to handle test mocking
 _ImportError = None
 try:
@@ -447,7 +450,6 @@ def consult_grok(query: str) -> str:
         )
     except (ImportError, AttributeError) as exc:
         logger.warning("Tool execution failed (consult_grok logging): %s", exc)
-        pass
 
     # Generate Lightning invoice for monetization (unless free mode)
     invoice_info = ""
@@ -456,12 +458,11 @@ def consult_grok(query: str) -> str:
             from lightning.factory import get_backend as get_ln_backend
 
             ln = get_ln_backend()
-            sats = min(settings.grok_max_sats_per_query, 100)
-            inv = ln.create_invoice(sats, f"Grok query: {query[:50]}")
+            sats = min(settings.grok_max_sats_per_query, settings.grok_sats_hard_cap)
+            inv = ln.create_invoice(sats, f"Grok query: {query[:_INVOICE_MEMO_MAX_LEN]}")
             invoice_info = f"\n[Lightning invoice: {sats} sats — {inv.payment_request[:40]}...]"
         except (ImportError, OSError, ValueError) as exc:
             logger.warning("Tool execution failed (Lightning invoice): %s", exc)
-            pass
 
     result = backend.run(query)
 
@@ -940,7 +941,7 @@ def _merge_catalog(
                 "available_in": available_in,
             }
     except ImportError:
-        pass
+        logger.debug("Optional catalog %s.%s not available", module_path, attr_name)
 
 
 def get_all_available_tools() -> dict[str, dict]: