Consolidation pass over the fallback feature, no intended behavior
changes beyond noted validation and event-shape cleanups:
- Unify the two parallel notice types: FallbackPlanNotice is gone;
ModelFallbackNotice now owns the runtime NoNearbyReasoningLevel case
and the shared ChainEmpty wording. Notices emit through a new
Emitter::notice_scoped with their own level, and each distinct notice
is emitted once per run instead of on every LLM call.
- Move canonical_model_id onto Catalog so chain keys are written and
read through one function; reject provider-qualified fallback keys,
which could never match at dispatch and were silently dead config.
- Type FallbackTarget as ProviderId/ModelId, removing repeated
ProviderId::new re-wrapping at every use site.
- Derive FallbackPlan's current route from a position index instead of
storing current/requested_controls copies; advance() no longer has
unreachable None branches.
- Bundle the agent invocation's live state (session, bridge, lease,
forwarder, accounting) into LiveAgentInvocation; failover_agent_session
drops from 21 parameters to 7 and the six copies of the
abort/discard/classify teardown collapse into two methods.
- Share one route_request builder between one_shot and its failover
loop; complete_one_shot_request takes the request by value instead of
deep-cloning the message payload per call.
- Event::Failover carries FailoverProps directly; the props' original
route and attempt fields are now required, and reasoning efforts are
typed ReasoningEffort instead of strings.
- Reuse RunModelSettings/RunModelControls in fabro-api via
with_replacement, add the missing controls property to the OpenAPI
schema, regenerate the TS client, and add the type-identity/JSON
parity test.
- Smaller cleanups: ReasoningEffort::closest_supported uses enum
discriminants; ModelFallbackPolicy gains len(); resolve_model_fallbacks
takes a provider slice; duplicate-target filtering lives only in the
resolver.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
