# Concelier PREP Notes — 2025-11-20

Owner: Concelier Core Guild · Scheduler Guild · Data Science Guild
Scope: Provide traceable prep outputs for PREP-CONCELIER-GRAPH-21-002-PLATFORM-EVENTS-S and PREP-CONCELIER-LNM-21-002-WAITING-ON-FINALIZE so downstream tasks can proceed without blocking on missing contracts.

## 1) `sbom.observation.updated` platform event (Graph-21-002)
- Goal: publish deterministic, facts-only observation updates for graph overlays; no derived judgments.
- Proposed envelope (draft for Scheduler/Platform Events review):
  - `event_type`: `sbom.observation.updated`
  - `tenant_id` (string, required)
  - `advisory_ids` (array of strings; upstream IDs as-ingested)
  - `observation_ids` (array of stable per-observation IDs emitted by LNM storage)
  - `source` (string; advisory source slug)
  - `version_range` (string; original upstream semantics)
  - `occurred_at` (ISO-8601 UTC, produced by Concelier at write time; deterministic)
  - `trace` (object; optional provenance pointers, DSSE envelope digest with alg/id fields)
- Delivery and wiring expectations:
  - Publisher lives in `StellaOps.Concelier.Core` after linkset/observation persistence.
  - Scheduler binding: NATS/Redis topic `concelier.sbom.observation.updated`; ack + idempotent replay friendly; max delivery once semantics via message ID = `<tenant>:<observation_id>::<digest>`.
  - Telemetry: counter `concelier_events_observation_updated_total{tenant,source,result}`; log template includes `tenant`, `advisory_id`, `observation_id`, `event_id`.
  - Offline posture: allow emitting into local bus, enqueue to file-backed spool when offline; retry with deterministic ordering by `(tenant, observation_id)`.
- Open questions to resolve in impl task:
  - Final topic naming and DSSE requirement (optional vs required per deployment).
  - Whether to include component alias list in the event payload or expect consumers to join via API.

## 2) LNM fixtures + precedence markers (LNM-21-002)
- Goal: unblock correlation pipelines and downstream linkset tasks by defining required fixture shape and precedence rules.
- Fixture requirements (additive to frozen LNM v1 schema):
  - Provide at least three sources with conflicting severity/CVSS to exercise conflict markers.
  - Include overlapping version ranges to validate precedence tie-breakers.
  - Each fixture must include `provenance` (source, fetch_time, collector) and `confidence` hints.
- Precedence rule proposal for review:
  1. Prefer explicit source ranking table (to be agreed) over recency.
  2. If ranking ties, prefer narrower version ranges, then higher confidence, then stable lexical order of `(source, advisory_id)`.
  3. Never collapse conflicting fields; emit `conflicts[]` entries with reason codes `severity-disagree`, `cvss-disagree`, `reference-disagree`.
- Delivery path for fixtures once agreed: `src/Concelier/seed-data/lnm/v1/fixtures/*.json` with deterministic ordering; wire into `StellaOps.Concelier.Core.Tests` harness.
- Next actions captured for implementation task:
  - Confirm ranking table and conflict reason code list with Cartographer/Data Science.
  - Drop initial fixtures into the above path and reference them from the implementation tasks’ tests.

## Handoff
- This document is the published prep artefact requested by PREP-CONCELIER-GRAPH-21-002-PLATFORM-EVENTS-S and PREP-CONCELIER-LNM-21-002-WAITING-ON-FINALIZE. Downstream tasks should cite this file until the final schemas/fixtures are merged.