EXC-END-01Tier IIException Handling & Graceful Degradation

Graceful Degradation Path

When the primary pathway fails, the agent falls back to a reduced-capability alternative rather than returning nothing.

Runtime: TerminateAgentOps: Operate & MonitorSee on the matrix →
TIERED FALLBACK PATHS Primary · Full CapabilityRAG · all tools · personalisation Secondary · Reducedgeneral knowledge · disclose reduction Tertiary · Minimalcached / static response Human Handoffwith full contextEach tier is labelled honestly to the user — silent degradation destroys trust.
In Plain English

This page is the complete instruction page for one pattern called "Graceful Degradation Path." It explains the problem this pattern solves, the idea behind the solution, when you should (and should not) use it, and what happens afterward — both the good effects and the costs.

This matters because building AI agents is not just about making them clever. It is also about making them safe and predictable. Following a well-tested pattern like this one helps avoid common mistakes, and shows you exactly which safety rules and regulations it connects to, listed under "Standards Mesh" on this page.

Context

A RAG agent whose index is down can still answer from general knowledge with a caveat. A scheduling agent without calendar access can still draft the invite. Returning "error" is rarely the right ending.

Problem

Binary success/failure ignores the space of useful-but-reduced responses.

Forces

  • Capability fidelity vs availability
  • User expectation management

Solution

Define tiered fallback paths: primary → secondary → tertiary → human. Each tier is clearly labelled to the user (e.g. "knowledge-base unavailable; answering from general knowledge — please verify"). Fallback decisions are logged for observability.

Applicability

  • User-facing agents
  • Agents with critical external dependencies
  • Reliability-sensitive deployments

Anti-Patterns

  • Silently falling back without telling the user
  • "Fallback" that is the same path with worse prompt

Consequences

  • +Resilience with honesty
  • +Reduced mean time to useful
  • Designing fallback paths is work
  • Users may conflate tiers