Fast Response

Overview

fast_response is a route-local plugin that returns a deterministic fallback message immediately.

It aligns to config/plugin/fast-response/busy.yaml.

Key Advantages

• Short-circuits expensive routes when a lightweight fallback is enough.
• Keeps overload behavior local to the route that needs it.
• Makes the fallback message explicit in config.

What Problem Does It Solve?

Some routes should degrade gracefully instead of waiting for the full model path. fast_response gives those routes an immediate response path without changing global behavior.

When to Use

• the route needs a cheap fallback under overload or maintenance conditions
• a deterministic response is acceptable for this traffic class
• fallback behavior should stay local to one route

Configuration

Use this fragment under routing.decisions[].plugins:

plugin:
  type: fast_response
  configuration:
    message: The primary model is saturated, so a lightweight response was returned immediately.