# Review: AD-608 Retroactive Memory Evolution (Re-review #2)

**Prompt:** prompts/ad-608-retroactive-memory-evolution.md
**Reviewer:** Architect
**Date:** 2026-04-27 (third pass)
**Verdict:** ✅ Approved
**Previous Verdict:** ⚠️ Conditional

## Improvements Since Prior Review
- **`update_episode_metadata()` body now fully specified** in Section 3c with ChromaDB read-modify-write pattern, error handling, and return type.
- `_propagate_metadata_reverse` and `_classify_relation` helpers fully defined with relation reverse-map (causal↔caused_by, follows↔followed_by, etc.) and time-delta + anchor-overlap classification heuristic.
- `_add_relation` consolidates the cap check, dup check, and metadata write — clean shared path.
- Bidirectional propagation explicit in `evolve_on_store`.
- Late-bind setter `set_retroactive_evolver` for breaking init cycles.
- Performance budget restated (<10ms per store).

## Required
None.

## Recommended
- `_add_relation` uses `getattr(mem, 'update_episode_metadata', None)` even though `update_episode_metadata` is defined as a public method on `EpisodicMemory` in this same prompt. The defensive lookup is unnecessary; call it directly. Same for `get_episode_metadata`.
- `get_episode_metadata` is referenced as a public API (`getattr(mem, 'get_episode_metadata', None)`) but **its body is never specified**. Either spell it out next to `update_episode_metadata` or note that the fallback path (skip metadata read) is acceptable. Currently the relation dedup check silently degrades to "always add" if `get_episode_metadata` is missing.
- `_classify_relation` uses `getattr(...)` chains for `timestamp`, `anchors`, etc. — Episode is a frozen dataclass with these fields always present. Use direct attribute access.

## Nits
- `relations_json` schema (list of `{related_episode_id, relation_type, timestamp}` dicts) is implicit in `_add_relation`. Consider documenting the JSON schema near the field declaration so future readers don't need to read both methods.

## Recommendation
Ship it. The `get_episode_metadata` spec gap is the most important Recommended item.
