# MeMind News Engine MVP

## Boundary

- `memind-news-engine` owns collection, event clustering, ranking, and briefing candidates.
- `Memind` consumes ranked candidates and owns page generation and delivery.
- `memind_adm` owns source configuration, ranking policy editing, review, run monitoring, and publish controls.
- The legacy `ops/` UI is not extended.

## Current pipeline

```text
Memind SearXNG query groups
  -> memind-news-engine HTTP API
  -> event clustering by canonical URL and title similarity
  -> deterministic rule score
  -> optional structured LLM assessment
  -> global score plus optional user-interest score
  -> breaking-news override
  -> category quotas and source diversity
  -> ranked candidates in the existing briefing prompt
  -> existing page generation, dedupe, image, and WeChat delivery guards
```

The first slice is deliberately deterministic. The model may provide the six semantic dimensions, but application code calculates the weighted score and owns final selection.

## Score contract

LLM assessment values are 0-10:

```json
{
  "importance": 8,
  "novelty": 9,
  "impact": 8,
  "credibility": 9,
  "relevance": 8,
  "actionability": 7,
  "category": "ai_tech",
  "reason": "A flagship model release changes capability and API economics."
}
```

Semantic score weights are 25% importance, 20% impact, 15% novelty, 15% credibility, 15% relevance, and 10% actionability. When the LLM assessment is present, global score is 35% rule score plus 65% semantic score. When a user-interest score is present, final score is 70% global plus 30% personal.

Breaking override is active when importance is at least 9, there are at least two distinct sources, and credibility is at least 8.

## Runtime controls

- `MEMIND_NEWS_ENGINE_DAILY_LIMIT`: selected event count, default `15`.
- `MEMIND_NEWS_ENGINE_MINIMUM_SCORE`: minimum final score, default `0` during the observation phase.
- `MEMIND_NEWS_ENGINE_URL`: independent service base URL; ranking is skipped when unset.
- `MEMIND_NEWS_ENGINE_API_TOKEN`: service-to-service bearer token.
- `MEMIND_NEWS_ENGINE_TIMEOUT_MS`: request timeout, default `5000`.

## Next slice

The engine repository now owns persistence migrations and the ranking API. Next work is the bounded LLM scoring worker, collection scheduler, and `memind_adm` management UI.