# Requirements: v1.79 Hypothesis Route Transition Gate Surface

## Milestone Goal

Close the next post-`v1.78` research-control gap so AITP can turn
route-transition eligibility into an operator-visible gate surface, instead of
forcing operators to infer whether yielding is blocked or available from
separate route-choice and helper artifacts.

## Completed Requirements

### Route Transition-Gate Surface

- [x] `REQ-HGATE-01`: runtime surfaces can materialize a bounded route
  transition-gate summary from route choice plus checkpoint/helper state.
- [x] `REQ-HGATE-02`: replay/read paths expose blocked versus available
  yielding instead of leaving transition gating implicit.

### Coexistence Rule

- [x] `REQ-HGATE-03`: the route transition-gate surface coexists cleanly with
  the current route_choice surface and helper mechanisms instead of
  auto-triggering runtime mutation.

### Verification

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

## Requirement Outcomes

- `REQ-HGATE-01`: validated through `route_transition_gate` payload
  materialization on the active research contract plus runtime protocol
  rendering.
- `REQ-HGATE-02`: validated through replay visibility for blocked,
  available, and checkpoint-required transition states.
- `REQ-HGATE-03`: validated through the bounded acceptance lane that keeps
  route transition gating, route choice, 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-HGATE-01 | Phase 153 | Complete |
| REQ-HGATE-02 | Phase 153 | Complete |
| REQ-HGATE-03 | Phase 153 | Complete |
| REQ-VERIFY-01 | Phase 153 | Complete |
