correlator: judge each scene on its own embedding + severity (server-26#80, #95)

intelligence.py writes only the primary scene's embedding and severity to
calls/{id}. _build_context read them back off the call doc, so every
non-primary scene of a multi-scene call was correlated against scene 1's
semantic vector and severity rung: a scene about a different event scored
on the embedding path against the wrong incident, and could inherit a
minor/moderate/major severity it never had, clearing the creation gate on
borrowed weight. Same defect and same fix as the #87 coords leak.

- _build_context / preview_correlation / correlate_call: take embedding and
  severity as params; drop the call_doc.get() fallbacks. A scene that
  passes none has none, and is judged thin on its own signal.
- upload.py: both scene loops pass scene["embedding"] / scene["severity"];
  _correlate_with_consensus forwards them. The no-scene unclassified branch
  passes neither (correct: no scene, judged thin).
- recorrelation_sweep: passes the call doc's stored values explicitly
  (whole-call re-link, link-only, so a borrowed severity cannot create).
- intelligence.py: SCENE DETECTION prompt tightened toward one scene
  (server-26#5, partial) - MULTIPLE only for genuinely separate events,
  "when unsure, one scene", plus a not-a-new-scene list.
- test_incident_identity.py: +2 regression tests mirroring the #87 test.

Full c2-core suite green (295 passed). #5 prompt change is unmeasured -
needs a scoped correlation-only window. Known remaining legs, tracked
separately: llm_correlator._call_block still reads the whole-call
transcript per scene; content-divergence veto skips on a None embedding.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

drb-c2-core/app/internal/incident_correlator.py

@@ -668,10 +668,17 @@ async def correlate_call(
     vehicles: Optional[list[str]] = None,
     cleared_units: Optional[list[str]] = None,
     reassignment: bool = False,
+    embedding: Optional[list] = None,
+    severity: Optional[str] = None,
 ) -> Optional[str]:
     """
     Link call_id to an existing incident or create a new one.
     Thin wrapper: builds context → runs rules decision → commits.
+
+    ``embedding`` and ``severity`` are the SCENE's own values (server-26#80/#95).
+    Callers that re-correlate a whole call rather than a scene — the
+    recorrelation sweep — pass the call doc's stored values explicitly; they are
+    no longer read from the doc inside _build_context.
     """
     ctx = await _build_context(
         call_id=call_id, units=units, vehicles=vehicles, cleared_units=cleared_units,
@@ -679,6 +686,7 @@ async def correlate_call(
         system_id=system_id, talkgroup_id=talkgroup_id, talkgroup_name=talkgroup_name,
         tags=tags, incident_type=incident_type, location=location,
         reassignment=reassignment, create_if_new=create_if_new,
+        embedding=embedding, severity=severity,
     )
     decision = _run_decision(ctx)
     return await _apply_and_log(decision, ctx)
@@ -700,6 +708,8 @@ async def preview_correlation(
     vehicles: Optional[list[str]] = None,
     cleared_units: Optional[list[str]] = None,
     reassignment: bool = False,
+    embedding: Optional[list] = None,
+    severity: Optional[str] = None,
 ) -> dict:
     """
     Run the rules engine and return the decision WITHOUT committing to Firestore.
@@ -720,6 +730,7 @@ async def preview_correlation(
         system_id=system_id, talkgroup_id=talkgroup_id, talkgroup_name=talkgroup_name,
         tags=tags, incident_type=incident_type, location=location,
         reassignment=reassignment, create_if_new=create_if_new,
+        embedding=embedding, severity=severity,
     )
     decision = _run_decision(ctx)
     return {"decision": decision, "ctx": ctx}
@@ -752,6 +763,8 @@ async def _build_context(
     location: Optional[str],
     reassignment: bool,
     create_if_new: bool,
+    embedding: Optional[list] = None,
+    severity: Optional[str] = None,
 ) -> dict:
     now    = reference_time or datetime.now(timezone.utc)
     window = timedelta(hours=settings.correlation_window_hours)
@@ -777,11 +790,20 @@ async def _build_context(
     all_active = _drop_capped(all_active, now)
     recent     = [inc for inc in all_active if _within_window_of(inc, now, window)]
 
-    call_embedding = call_doc.get("embedding")
+    # embedding and severity come from the SCENE being correlated, not the call
+    # doc — server-26#80 / #95. intelligence.py writes only the primary scene's
+    # embedding and severity to calls/{id}, so reading them back here handed
+    # every non-primary scene the primary scene's semantic vector and severity
+    # rung: a scene about a different event scored against the wrong incident on
+    # the embedding path (:1166/:1205/:1533) and could inherit a minor/moderate/
+    # major severity it never had, clearing the creation gate on borrowed
+    # weight. Same failure and same fix as the #87 coords leak directly below —
+    # a scene that passes none has none, and is judged thin on its own signal.
+    call_embedding = embedding
     call_units     = units         if units         is not None else (call_doc.get("units")         or [])
     call_vehicles  = vehicles      if vehicles      is not None else (call_doc.get("vehicles")      or [])
     call_cleared   = cleared_units if cleared_units is not None else (call_doc.get("cleared_units") or [])
-    call_severity  = call_doc.get("severity") or "routine"
+    call_severity  = severity or "routine"
     # A string that is not a place is not a location anywhere downstream — not
     # in the fit tests, not in the thin-call test, not in the LLM prompt, and
     # not on the incident.  Its coordinates go with it: coords are geocoded

drb-c2-core/app/internal/intelligence.py

@@ -24,7 +24,16 @@ from app.internal.incident_correlator import clean_location, location_is_unit
 _PROMPT_TEMPLATE = """You are analyzing a P25 public safety radio recording. The audio was transcribed by Whisper through a digital radio vocoder, which introduces errors. Each numbered transmission is a separate PTT press from a different radio.
 
 SCENE DETECTION:
-A busy dispatch channel sometimes captures back-to-back conversations about multiple concurrent incidents in a single recording. Detect whether this recording contains ONE scene (all transmissions relate to a single event) or MULTIPLE scenes (clearly distinct dispatch conversations with different units being assigned, different locations, different event types). Assign short status transmissions (10-4, en route, acknowledgements) with no clear scene context to the most recent scene before them in the list.
+A busy dispatch channel sometimes captures back-to-back conversations about multiple concurrent incidents in a single recording. Your default is ONE scene. Return MULTIPLE scenes ONLY when the recording clearly contains two or more SEPARATE EVENTS — different incidents at different places, with no shared units, no shared subject, and no conversational thread connecting them.
+
+These do NOT make a new scene — keep them in the same scene:
+- a different unit or speaker joining the same event
+- a follow-up transmission about the same job (records check, case number, tow/mileage, a unit clearing, an ETA, a location correction)
+- the same subject or location being discussed again minutes later
+- an administrative or status exchange that follows an event on the same channel
+If you are unsure whether two exchanges are one event or two, treat them as ONE.
+
+Assign short status transmissions (10-4, en route, acknowledgements) with no clear scene context to the most recent scene before them in the list.
 
 Always respond with the scenes array, even for a single scene.
 

drb-c2-core/app/internal/recorrelation_sweep.py

@@ -90,6 +90,11 @@ async def _recorrelate_orphan(call: dict) -> bool:
         return False
 
     # All data needed for correlation was stored by the first-pass extraction.
+    # embedding/severity are no longer read from the call doc inside
+    # _build_context (server-26#80/#95) — the sweep re-links a whole call, not a
+    # scene, so it passes the call doc's stored (primary-scene) values here. It
+    # is link-only (create_if_new=False), so a borrowed severity cannot open a
+    # new incident off this path.
     incident_id = await incident_correlator.correlate_call(
         call_id        = call_id,
         node_id        = call.get("node_id", ""),
@@ -101,6 +106,8 @@ async def _recorrelate_orphan(call: dict) -> bool:
         location       = call.get("location"),
         location_coords= call.get("location_coords"),
         cleared_units  = call.get("cleared_units") or [],
+        embedding      = call.get("embedding"),
+        severity       = call.get("severity"),
         reference_time = started_at,   # anchor window to when the call happened
         create_if_new  = False,        # never create — link-only
     )