# Phase 160: Hypothesis Route Transition Clearance Surface - Context

**Gathered:** 2026-04-12
**Status:** Ready for execution

<domain>
## Phase Boundary

This phase owns the next post-`v1.85` research-control slice.

The phase should:

- derive a bounded route transition-clearance summary from route transition
  escalation plus operator-checkpoint lifecycle context
- keep clearance visibility explicit without widening into fresh runtime
  mutation
- coexist with current route transition-escalation, route transition-repair,
  and helper mechanisms

</domain>

<decisions>
## Implementation Decisions

- **D-01:** Build on the existing route transition-escalation and helper
  surfaces instead of inventing a disconnected checkpoint-clearing subsystem.
- **D-02:** Keep the first slice declarative and operator-visible: summarize
  whether the transition is still checkpoint-blocked or has been released, do
  not widen into fresh runtime mutation.
- **D-03:** Preserve the current action queue, transition repair/escalation,
  and helper mechanisms as the execution-level machinery.
- **D-04:** Add one isolated acceptance lane so the transition-clearance path
  can close independently.

</decisions>

<canonical_refs>
## Canonical References

- `.planning/REQUIREMENTS.md`
- `.planning/ROADMAP.md`
- `research/knowledge-hub/knowledge_hub/runtime_read_path_support.py`
- `research/knowledge-hub/knowledge_hub/topic_replay.py`
- `.planning/phases/160-hypothesis-route-transition-clearance-surface/PHASE.md`

</canonical_refs>

<deferred>
## Deferred Ideas

- fresh runtime mutation after checkpoint clearance becomes explicit
- consuming operator answers as automatic route-state mutation
- helper-driven checkpoint execution without an explicit clearance surface

</deferred>

---

*Phase: 160-hypothesis-route-transition-clearance-surface*
*Context gathered: 2026-04-12*
