Core concepts

Five ideas explain almost everything routsi does.

• model: "auto" — routsi classifies the task (low / medium / high) and picks a tier.
• A concrete model name (e.g. gpt-strong, devin/claude-opus-4.8) is a hard bypass — no routing.
• dynamic-1 — a named group you define with levels: {low, medium, high}; the task is classified and dispatched to the mapped member.
• Sticky by conversation id — a thread pins to its member and only ever escalates, never downgrades.
• Pre-request routing only — routsi never touches a response mid-stream; forwards are raw byte passthrough with model + auth rewrite.

See these in action: Routing & stickiness for the mechanics, How auto decides for the exact classification rules, or Scenarios for copy-paste examples.

Next: models.yaml →