chore: release 0.2.39

docs/ROUTING.md

@@ -177,7 +177,13 @@ code        = ["claude-sonnet", "gpt"] # code goes to the strongest coder first
 
 A matching rule's models go **first** in the candidate chain; the complexity
 chain follows as fallback, so a task pin never weakens failover. Tasks without
-a rule route by complexity alone. The available labels come from the router
+a rule route by complexity alone.
+
+**Exception — high complexity escalates.** When the router rates a request
+`high` (and a `high` chain is configured), the tier chain leads and the task
+rule demotes to fallback. Otherwise a rule like `code → cheap-model` would pin
+even the hardest prompts to the cheap model and the tier system would never
+get a say. Low/medium keep task-rule-first semantics. The available labels come from the router
 (`GET /v1/taxonomies`) — the admin console's Routing page builds the editor
 from your account's live taxonomy and shows each task's share of recent
 traffic. When a rule supplied the head of the chain the response reports