# Requirements: v1.78 Hypothesis Route Choice Surface

## Milestone Goal

Close the next post-`v1.77` research-control gap so AITP can turn the current
local route plus the primary parked-route handoff candidate into an
operator-visible route choice surface, instead of forcing operators to infer
stay-local versus yield choice from separate current-route and handoff
artifacts.

## Completed Requirements

### Route Choice Surface

- [x] `REQ-HCHOICE-01`: runtime surfaces can materialize a bounded route choice
  summary from current-route activation plus the primary handoff candidate.
- [x] `REQ-HCHOICE-02`: replay/read paths expose stay-local versus
  yield-to-handoff choice instead of leaving that choice implicit.

### Coexistence Rule

- [x] `REQ-HCHOICE-03`: the route choice surface coexists cleanly with the
  current current-route-choice, route_activation, route_reentry, and
  route_handoff surfaces plus helper mechanisms instead of auto-triggering
  runtime mutation.

### Verification

- [x] `REQ-VERIFY-01`: the milestone closes with one bounded isolated
  route choice acceptance path plus targeted regression coverage for the new
  choice surface.

## Requirement Outcomes

- `REQ-HCHOICE-01`: validated through `route_choice` payload materialization on
  the active research contract plus runtime protocol rendering.
- `REQ-HCHOICE-02`: validated through replay visibility for stay-local and
  yield-to-handoff options.
- `REQ-HCHOICE-03`: validated through the bounded acceptance lane that keeps
  route choice, route handoff, and helper mechanisms visible without automatic
  runtime mutation.
- `REQ-VERIFY-01`: validated through the dedicated isolated acceptance lane and
  targeted replay/schema/runtime regression slices.

## Traceability

| Requirement | Phase | Status |
|-------------|-------|--------|
| REQ-HCHOICE-01 | Phase 152 | Complete |
| REQ-HCHOICE-02 | Phase 152 | Complete |
| REQ-HCHOICE-03 | Phase 152 | Complete |
| REQ-VERIFY-01 | Phase 152 | Complete |
