docs: list remittances.py in api_routers/ Project layout

Another router extraction landed: api_routers/remittances.py now owns
the three /api/remittances[...] routes (list, stream, detail). Pure
code-organization move from api.py — no new endpoints, no new
functionality.

Update the Project layout block to list remittances.py alongside the
other 9 routers with the routes it owns.

README.md

@@ -155,6 +155,7 @@ parses and rejects claims, the inbox reflects the new
 | POST   | `/api/inbox/candidates/{remit_id}/match`      | Manual match. `409` if the claim state moved out from under us.  |
 | POST   | `/api/inbox/candidates/dismiss`               | `{pairs: [{claim_id, remit_id}]}`. Session-scoped.               |
 | POST   | `/api/inbox/rejected/resubmit`                | `{claim_ids: [...]}`. `200` with `conflicts` for non-rejected.   |
+| POST   | `/api/inbox/payer-rejected/acknowledge`       | `{claim_ids: [...], actor: "..."}`. Bulk-acknowledge payer rejections. Idempotent. `200` with `transitioned` / `already_acked` / `not_found` / `not_rejected` counts. Writes an audit event per transition; never overwrites the underlying 277CA rejection. |
 | GET    | `/api/inbox/export.csv?lane=<lane>`           | Streams CSV of the lane's rows.                                  |
 
 ## Outbound 837 Serializer
@@ -321,8 +322,9 @@ both be true for the same claim.
 
 The `audit_log` table is the canonical record of every state transition
 the system has ever observed — claim lifecycle, reconciliation
-decisions, config reloads, SFTP submissions, 277CA rejects. SP11 made
+decisions, config reloads, SFTP submissions, 277CA rejects, Payer-Rejected
-it tamper-evident: every row carries a SHA-256 hash of
+acknowledgements, SQLCipher key rotations. SP11 made it tamper-evident:
+every row carries a SHA-256 hash of
 `(prev_hash || row_payload)`, forming a chain back to a genesis row.
 Any `INSERT`, `UPDATE`, or `DELETE` that breaks the chain is detectable
 in a single walk.
@@ -357,6 +359,40 @@ operator has created the Keychain entry on first run. See
 for the one-time setup recipe and the HIPAA Security Rule §164.312(a)(2)(iv)
 mapping.
 
+### Key rotation
+
+The DB encryption key is rotated in place via `POST /api/admin/db/rotate-key`.
+The handler:
+
+1. Generates a fresh 256-bit CSPRNG key (`db_crypto.generate_db_key()`).
+2. Persists the new key to the Keychain under the same
+   `cyclone.db.key` account (overwriting the old one).
+3. Disposes the SQLAlchemy engine so pooled connections release the
+   file (SQLCipher refuses to `PRAGMA rekey` while another connection
+   holds the DB).
+4. Opens with the old key, issues `PRAGMA rekey`, and verifies the
+   schema survived (table-count sanity check).
+5. Rebuilds the engine with the new key.
+6. Writes a `db.key_rotated` audit event carrying the SHA-256
+   fingerprints of the old and new keys (first 8 hex chars) plus the
+   post-rotation `table_count`.
+
+When SQLCipher is enabled the engine uses SQLAlchemy's `NullPool`
+instead of the default `QueuePool`. `QueuePool` returns connections to
+a shared queue that any thread can pull from, which breaks SQLCipher's
+thread affinity. `NullPool` trades connection reuse for thread safety
+— the only correct behavior under FastAPI's per-request threadpool.
+
+The rotation endpoint is serialized with a module-level
+`threading.Lock` (one rotation in flight at a time), returns `409` if
+a rotation is already running, `400` if encryption is not enabled,
+and `503` with a `reason` on `PRAGMA rekey` or Keychain failure so the
+operator can take the next step without parsing the traceback.
+
+| Method | Path                              | Notes                                                          |
+| ------ | --------------------------------- | -------------------------------------------------------------- |
+| POST   | `/api/admin/db/rotate-key`        | Rotate the SQLCipher key in place. Audit-logged.                |
+
 ## SFTP Wire-Up (paramiko)
 
 The `clearhouse.submit` endpoint uses `paramiko` to push a batch of
@@ -382,6 +418,29 @@ was a one-file change (`sftp_paramiko.py` replacing `sftp_stub.py`).
 the `paramiko` extras aren't installed so the test suite stays green on
 Linux dev boxes.
 
+## Batches, Reconciliation, and Activity
+
+These read/write endpoints are the core operator surface for browsing
+the parsed record and acting on matches. They predate the per-SP
+endpoint reference sections in the **Roadmap** and are listed here in
+one place so the route inventory stays discoverable.
+
+| Method | Path                                          | Notes                                                            |
+| ------ | --------------------------------------------- | ---------------------------------------------------------------- |
+| GET    | `/api/batches`                                | All parsed batches, newest first. `?limit=` (1–1000, default 100). |
+| GET    | `/api/batches/{batch_id}`                     | One batch detail (envelope, claims / remits, validation summary). |
+| GET    | `/api/batch-diff?a=<id>&b=<id>`               | Side-by-side diff of two batches: `added` / `removed` / `changed` claims + envelope metadata for each. Both query params required. |
+| GET    | `/api/reconciliation/unmatched`               | `{"claims": [...], "remittances": [...]}` — every Claim with no paired Remittance and vice versa. The two lists are always present (empty list, never absent) so the UI can index unconditionally. |
+| POST   | `/api/reconciliation/match`                   | Body `{claim_id, remit_id}`. Manually pair a claim with a remit. `400` on missing ids, `404` on unknown id, `409` on already-matched or terminal-state claim. |
+| POST   | `/api/reconciliation/unmatch`                 | Body `{claim_id}`. Remove the current match and reset the claim to `submitted`. `404` on unknown id, `409` on no current match. |
+| GET    | `/api/providers`                              | Distinct providers across parsed claims. `?npi=`, `?state=`, `?limit=`, `?offset=`. Distinct from `/api/config/providers/{npi}` (SP9 config table) — this endpoint surfaces providers derived from the parsed claim stream. |
+| GET    | `/api/activity`                               | Recent activity events. `?kind=`, `?since=`, `?limit=` (1–500, default 200). Powers the Activity page; the streaming counterpart `/api/activity/stream` is documented under **Live updates**. |
+
+The per-SP endpoint blocks at the bottom of the **Roadmap** cover the
+SP-specific routes (parse, 999/TA1/277CA, Inbox, claim drawer, line
+reconciliation, outbound 837, multi-payer config, audit log, 277CA,
+key rotation, payer-rejected acknowledge).
+
 ## Persistence
 
 Parsed batches, claims, remittances, matches, 277CA rejections,
@@ -415,8 +474,20 @@ backup API).
 .
 ├── backend/
 │   ├── src/cyclone/
-│   │   ├── api.py             # FastAPI app, GET + parse routes, /api/{resource}/stream
+│   │   ├── api.py             # FastAPI app + parse routes; mounts api_routers/* sub-apps
 │   │   ├── api_helpers.py     # NDJSON / content-negotiation / live-tail helpers
+│   │   ├── api_routers/       # FastAPI APIRouters extracted from api.py
+│   │   │   ├── health.py      #   GET /api/health
+│   │   │   ├── acks.py        #   GET /api/acks, /api/acks/{id}
+│   │   │   ├── ta1_acks.py    #   GET /api/ta1-acks, /api/ta1-acks/{id}
+│   │   │   ├── activity.py    #   GET /api/activity, /api/activity/stream
+│   │   │   ├── batches.py     #   GET /api/batches, /api/batches/{id}, /api/batch-diff
+│   │   │   ├── claims.py      #   GET /api/claims, /api/claims/stream, /api/claims/{id},
+│   │   │   │                  #   /api/claims/{id}/serialize-837, /api/claims/{id}/line-reconciliation
+│   │   │   ├── remittances.py #   GET /api/remittances, /api/remittances/stream, /api/remittances/{id}
+│   │   │   ├── providers.py   #   GET /api/providers
+│   │   │   ├── clearhouse.py  #   GET /api/clearhouse, POST /api/clearhouse/submit
+│   │   │   └── config.py      #   /api/config/providers[/...], /api/config/payers[/...], /api/admin/reload-config
 │   │   ├── pubsub.py          # in-process EventBus (drop-oldest, per-kind fan-out)
 │   │   ├── store.py           # CycloneStore, mappers, publish-on-write
 │   │   ├── db.py              # SQLAlchemy engine, session factory, ORM models
@@ -473,7 +544,7 @@ backup API).
 
 ## Roadmap
 
-Sub-projects 2 through 13 are **shipped**. See the [completeness
+Sub-projects 2 through 15 are **shipped**. See the [completeness
 review](docs/reviews/2026-06-20-cyclone-completeness-review.md) for
 the honest gap analysis against the industry definition of a HIPAA
 clearinghouse — the short version is that the local-only,
@@ -484,6 +555,19 @@ scope.
 
 Shipped sub-projects (most recent first):
 
+- **Sub-project 15 (shipped) — SQLCipher key rotation.** In-place
+  rotation via `PRAGMA rekey`, serialized through a module-level
+  `threading.Lock` and a SQLAlchemy `NullPool` to keep SQLCipher
+  thread-affine under FastAPI's per-request threadpool. Writes a
+  `db.key_rotated` audit event with old + new key fingerprints and
+  post-rotation `table_count`. See
+  [Encryption at Rest — Key rotation](#key-rotation).
+- **Sub-project 14 (shipped) — 5-lane Inbox UI.** The Payer-Rejected
+  lane is now rendered in the Inbox alongside Rejected / Candidates /
+  Unmatched / Done today. New bulk action
+  `POST /api/inbox/payer-rejected/acknowledge` drops claims from the
+  working surface without erasing the original 277CA rejection event
+  (audit log stays intact, SP11).
 - **Sub-project 13 (shipped) — SFTP wire-up.** `paramiko`-backed
   `SftpClient` replaces the SP9 stub. The clearhouse.submit endpoint
   actually pushes to
@@ -752,6 +836,34 @@ the one-time setup recipe.
   `mft.gainwelltechnologies.com:/CO XIX/PROD/coxix_prod_11525703/FromHPE`.
   SFTP credentials are fetched from the macOS Keychain at call time.
 
+### SP14 endpoints (5-lane Inbox UI + acknowledge)
+
+- `GET /api/inbox/lanes` — same shape as SP6; the `payer_rejected`
+  lane payload now also includes
+  `payer_rejected_acknowledged_at` + `payer_rejected_acknowledged_actor`
+  per row so the UI can badge acknowledged claims (forward-compat for
+  a future "Recently acknowledged" view).
+- `POST /api/inbox/payer-rejected/acknowledge` — bulk-acknowledge
+  Payer-Rejected claims. Body: `{claim_ids: [...], actor: "..."}`.
+  Idempotent. Response: `200` with
+  `{transitioned, already_acked, not_found, not_rejected}`. Writes an
+  `inbox.payer_rejected_acknowledged` audit event per transition.
+  Acknowledgement hides a claim from the lane but never overwrites
+  `payer_rejected_at` / `payer_rejected_reason` /
+  `payer_rejected_by_277ca_id` — the original 277CA evidence stays
+  intact in the audit log.
+
+### SP15 endpoints (SQLCipher key rotation)
+
+- `POST /api/admin/db/rotate-key` — rotate the SQLCipher DB key in
+  place. Generates a fresh 256-bit key, writes it to the Keychain
+  (overwriting `cyclone.db.key`), disposes the engine, issues
+  `PRAGMA rekey`, verifies the schema, rebuilds the engine. Writes
+  a `db.key_rotated` audit event with old + new key fingerprints
+  and `table_count`. Returns `409` when a rotation is already in
+  flight, `400` when encryption is not enabled, `503` with a
+  `reason` on `PRAGMA rekey` or Keychain failure.
+
 ## License
 
 No license file yet; this is internal-use software. Add a `LICENSE` file

backend/src/cyclone/api.py

@@ -141,11 +141,37 @@ app.add_middleware(
 # and are wired in here. (Kept as a top-level package rather than nested
 # under `cyclone.api` so the existing ``cyclone.api`` module path keeps
 # working — Python prefers packages over same-named modules.)
-from cyclone.api_routers import acks, health, ta1_acks  # noqa: E402
+from cyclone.api_routers import (  # noqa: E402
+    acks,
+    activity,
+    batches,
+    claims,
+    clearhouse,
+    config,
+    health,
+    providers,
+    remittances,
+    ta1_acks,
+)
 
 app.include_router(health.router)
 app.include_router(acks.router)
 app.include_router(ta1_acks.router)
+app.include_router(providers.router)
+app.include_router(clearhouse.router)
+app.include_router(config.router)
+app.include_router(activity.router)
+app.include_router(batches.router)
+app.include_router(claims.router)
+app.include_router(remittances.router)
+
+# Backwards-compat re-exports: test_api_stream_live.py imports these
+# names directly from ``cyclone.api`` to invoke the endpoint coroutines
+# in-process. Re-pointing at the router keeps the public surface stable
+# while the bodies live in the routers package.
+activity_stream = activity.activity_stream_endpoint
+claims_stream = claims.claims_stream_endpoint
+remittances_stream = remittances.remittances_stream_endpoint
 
 
 def _resolve_payer(name: str) -> PayerConfig:
@@ -1141,431 +1167,10 @@ def inbox_export_csv(lane: str):
     )
 
 
-# --------------------------------------------------------------------------- #
+# --- /api/batches lives in cyclone.api_routers.batches ---
-# GET endpoints (read views over the in-memory store)
-# --------------------------------------------------------------------------- #
 
 
-def _batch_summary_claim_count(rec: BatchRecord) -> int:
+# --- /api/claims lives in cyclone.api_routers.claims ---
-    """Return the number of claims on a batch, handling both 837P and 835."""
-    if rec.kind == "837p":
-        return len(rec.result.claims)  # type: ignore[attr-defined]
-    if rec.kind == "835":
-        return len(rec.result.claims)  # type: ignore[attr-defined]
-    return 0
-
-
-@app.get("/api/batches")
-def list_batches(
-    request: Request,
-    limit: int = Query(100, ge=1, le=1000),
-) -> Any:
-    """Summary of all parsed batches, newest first."""
-    records = store.list(limit=limit)
-    items = [
-        {
-            "id": r.id,
-            "kind": r.kind,
-            "inputFilename": r.input_filename,
-            "parsedAt": r.parsed_at.isoformat().replace("+00:00", "Z"),
-            "claimCount": _batch_summary_claim_count(r),
-        }
-        for r in records
-    ]
-    all_records = store.all()
-    total = len(all_records)
-    returned = len(items)
-    has_more = total > returned
-    if _wants_ndjson(request):
-        return StreamingResponse(
-            _ndjson_stream_list(items, total, returned, has_more),
-            media_type="application/x-ndjson",
-        )
-    return {
-        "items": items,
-        "total": total,
-        "returned": returned,
-        "has_more": has_more,
-    }
-
-
-@app.get("/api/batches/{batch_id}")
-def get_batch(batch_id: str) -> Any:
-    rec = store.get(batch_id)
-    if rec is None:
-        raise HTTPException(
-            status_code=404,
-            detail={"error": "Not found", "detail": f"Batch {batch_id} not found"},
-        )
-    return json.loads(rec.result.model_dump_json())
-
-
-@app.get("/api/claims")
-def list_claims(
-    request: Request,
-    batch_id: str | None = Query(None),
-    status: str | None = Query(None),
-    provider_npi: str | None = Query(None),
-    payer: str | None = Query(None),
-    date_from: str | None = Query(None),
-    date_to: str | None = Query(None),
-    sort: str | None = Query(None),
-    order: str = Query("desc"),
-    limit: int = Query(100, ge=1, le=1000),
-    offset: int = Query(0, ge=0),
-) -> Any:
-    common = dict(
-        batch_id=batch_id,
-        status=status,
-        provider_npi=provider_npi,
-        payer=payer,
-        date_from=date_from,
-        date_to=date_to,
-    )
-    items = list(store.iter_claims(
-        sort=sort, order=order, limit=limit, offset=offset, **common,
-    ))
-    total = len(list(store.iter_claims(**common)))
-    returned = len(items)
-    has_more = total > offset + returned
-    if _wants_ndjson(request):
-        return StreamingResponse(
-            _ndjson_stream_list(items, total, returned, has_more),
-            media_type="application/x-ndjson",
-        )
-    return {
-        "items": items,
-        "total": total,
-        "returned": returned,
-        "has_more": has_more,
-    }
-
-
-# --------------------------------------------------------------------------- #
-# Live-tail NDJSON streaming endpoints (Phase 3 — SP5)
-# --------------------------------------------------------------------------- #
-
-
-@app.get("/api/claims/stream")
-async def claims_stream(
-    request: Request,
-    status: str | None = Query(None),
-    provider_npi: str | None = Query(None),
-    payer: str | None = Query(None),
-    date_from: str | None = Query(None),
-    date_to: str | None = Query(None),
-    sort: str | None = Query(None),
-    order: str = Query("desc"),
-    limit: int = Query(100, ge=1, le=1000),
-) -> StreamingResponse:
-    """Stream Claims as NDJSON: snapshot first, then live events.
-
-    Wire format:
-      * ``{"type":"item","data":<claim>}`` per snapshot row, then per
-        new ``claim_written`` event
-      * ``{"type":"snapshot_end","data":{"count":N}}`` after the snapshot
-      * ``{"type":"heartbeat","data":{"ts":<iso>}}`` every
-        ``CYCLONE_TAIL_HEARTBEAT_S`` seconds when idle
-
-    Query params mirror :func:`list_claims` so a frontend can swap a
-    one-shot fetch for a tail with no URL surgery.
-
-    NOTE: registered before ``/api/claims/{claim_id}`` so the literal
-    ``stream`` path segment doesn't get matched as a claim id.
-    """
-    bus: EventBus = request.app.state.event_bus
-
-    async def gen() -> AsyncIterator[bytes]:
-        # 1. Snapshot (eager — iter_claims returns a list already).
-        rows = store.iter_claims(
-            status=status, provider_npi=provider_npi, payer=payer,
-            date_from=date_from, date_to=date_to,
-            sort=sort or "-submission_date", order=order, limit=limit,
-        )
-        for row in rows:
-            yield _ndjson_line({"type": "item", "data": row})
-        yield _ndjson_line({"type": "snapshot_end", "data": {"count": len(rows)}})
-
-        # 2. Subscribe + heartbeats.
-        async for chunk in _tail_events(request, bus, ["claim_written"]):
-            yield chunk
-
-    return StreamingResponse(gen(), media_type="application/x-ndjson")
-
-
-@app.get("/api/claims/{claim_id}")
-def get_claim_detail_endpoint(claim_id: str) -> dict:
-    """Return one claim with full drawer context (SP4).
-
-    Body shape is produced by :meth:`CycloneStore.get_claim_detail`:
-    header, state, service lines, diagnoses, parties, validation,
-    raw segments, ``stateHistory`` (most-recent-first, capped at 50),
-    and a populated ``matchedRemittance`` block when paired.
-
-    Path param is ``claim_id`` (matches the SP3 ``/api/acks/{ack_id}``
-    convention). Returns 404 — never 500 — on a missing claim so the
-    UI can distinguish "doesn't exist" from a transient fetch error.
-    """
-    body = store.get_claim_detail(claim_id)
-    if body is None:
-        raise HTTPException(
-            status_code=404,
-            detail={
-                "error": "Not found",
-                "detail": f"Claim {claim_id} not found",
-            },
-        )
-    return body
-
-
-@app.get("/api/claims/{claim_id}/serialize-837")
-def serialize_claim_as_837(claim_id: str):
-    """Return the claim as a regenerated X12 837P file (SP8).
-
-    Loads the ClaimOutput from the persisted ``raw_json`` and runs the
-    outbound serializer. Returns 404 if the claim doesn't exist, 422 if
-    the stored payload has no parseable ClaimOutput (data integrity
-    issue, not a transient failure).
-    """
-    with db.SessionLocal()() as s:
-        row = s.get(Claim, claim_id)
-        if row is None:
-            return JSONResponse(
-                {"error": "Not found", "detail": f"Claim {claim_id} not found"},
-                status_code=404,
-            )
-        if not row.raw_json:
-            return JSONResponse(
-                {
-                    "error": "Unprocessable",
-                    "detail": f"Claim {claim_id} has no raw_json; cannot serialize",
-                },
-                status_code=422,
-            )
-        try:
-            claim_obj = ClaimOutput.model_validate(row.raw_json)
-        except Exception as exc:
-            return JSONResponse(
-                {
-                    "error": "Unprocessable",
-                    "detail": f"Claim {claim_id} raw_json is malformed: {exc}",
-                },
-                status_code=422,
-            )
-
-    try:
-        text = serialize_837(claim_obj)
-    except SerializeError837 as exc:
-        return JSONResponse(
-            {"error": "Unprocessable", "detail": str(exc)},
-            status_code=422,
-        )
-
-    return Response(
-        content=text,
-        media_type="text/x12",
-        headers={
-            "Content-Disposition": f'attachment; filename="claim-{claim_id}.x12"'
-        },
-    )
-
-
-@app.get("/api/claims/{claim_id}/line-reconciliation")
-def get_claim_line_reconciliation(claim_id: str) -> dict:
-    """Per-line reconciliation view for the ClaimDrawer tab.
-
-    Spec §5.1. Returns the 837 service lines and 835 SVC composites
-    side-by-side, with per-line CAS adjustments and a summary block.
-
-    Architecture note: 837 service lines live in ``Claim.raw_json``
-    (not a separate ORM table), so the 837-side rows are read from the
-    JSON blob; the 835-side rows come from ``ServiceLinePayment`` ORM.
-    ``LineReconciliation.claim_service_line_number`` stores the 1-based
-    line number to join them.
-    """
-    from sqlalchemy import select
-    from cyclone.db import (
-        LineReconciliation, ServiceLinePayment, CasAdjustment,
-    )
-    import json as _json
-    from decimal import Decimal
-
-    with db.SessionLocal()() as s:
-        claim = s.get(db.Claim, claim_id)
-        if claim is None:
-            raise HTTPException(
-                status_code=404,
-                detail={"error": "Not found", "detail": f"Claim {claim_id} not found"},
-            )
-
-        # 837 service lines: from raw_json.
-        raw = claim.raw_json or {}
-        claim_lines_raw = raw.get("service_lines") or []
-        # Normalize to dicts for the response.
-        claim_lines = [_claim_line_dict(d) for d in claim_lines_raw]
-
-        # 835 service payments: ORM rows from the matched remit.
-        remits = list(
-            s.execute(
-                select(db.Remittance).where(db.Remittance.claim_id == claim_id)
-            ).scalars().all()
-        )
-        svc_payments: list[dict] = []
-        svc_ids: list[int] = []
-        if remits:
-            svc_rows = list(
-                s.execute(
-                    select(ServiceLinePayment).where(
-                        ServiceLinePayment.remittance_id.in_([r.id for r in remits])
-                    ).order_by(ServiceLinePayment.line_number)
-                ).scalars().all()
-            )
-            for svc in svc_rows:
-                d = _svc_to_dict(svc)
-                svc_payments.append(d)
-                svc_ids.append(svc.id)
-
-        # LineReconciliation rows.
-        lrs = list(
-            s.execute(
-                select(LineReconciliation).where(LineReconciliation.claim_id == claim_id)
-            ).scalars().all()
-        )
-        # Index by claim_service_line_number and service_line_payment_id.
-        lr_by_claim_num: dict[int, LineReconciliation] = {
-            lr.claim_service_line_number: lr for lr in lrs if lr.claim_service_line_number is not None
-        }
-        lr_by_svc: dict[int, LineReconciliation] = {
-            lr.service_line_payment_id: lr for lr in lrs if lr.service_line_payment_id is not None
-        }
-
-        # CAS rows grouped by svc id.
-        cas_by_svc: dict[int, list[CasAdjustment]] = {}
-        if svc_ids:
-            cas_rows = list(
-                s.execute(
-                    select(CasAdjustment).where(CasAdjustment.service_line_payment_id.in_(svc_ids))
-                ).scalars().all()
-            )
-            for c in cas_rows:
-                cas_by_svc.setdefault(c.service_line_payment_id, []).append(c)
-
-        # Build output lines array, preserving 837 order then 835-only.
-        svc_by_id: dict[int, dict] = {d["id"]: d for d in svc_payments}
-        lines_out: list[dict] = []
-        billed_total = Decimal("0")
-        paid_total = Decimal("0")
-        adjustment_total = Decimal("0")
-        matched_count = 0
-        used_svc_ids: set[int] = set()
-
-        for cl in claim_lines:
-            billed_total += Decimal(str(cl["charge"]))
-            lr = lr_by_claim_num.get(cl["line_number"])
-            if lr is None:
-                lines_out.append({
-                    "claim_service_line": cl,
-                    "service_line_payment": None,
-                    "status": "unmatched_837_only",
-                    "adjustments": [],
-                })
-                continue
-            svc_id = lr.service_line_payment_id
-            svc = svc_by_id.get(svc_id) if svc_id else None
-            if svc_id is not None:
-                used_svc_ids.add(svc_id)
-            cas_list = cas_by_svc.get(svc_id, []) if svc_id is not None else []
-            cas_total = sum((Decimal(str(c.amount)) for c in cas_list), Decimal("0"))
-            if svc:
-                paid_total += Decimal(str(svc["payment"]))
-            adjustment_total += cas_total
-            if lr.status == "matched":
-                matched_count += 1
-            lines_out.append({
-                "claim_service_line": cl,
-                "service_line_payment": svc,
-                "status": lr.status,
-                "adjustments": [
-                    {"group_code": c.group_code, "reason_code": c.reason_code,
-                     "amount": str(Decimal(str(c.amount)))}
-                    for c in cas_list
-                ],
-            })
-
-        # 835-only lines (no claim match).
-        for lr in lrs:
-            if lr.claim_service_line_number is not None:
-                continue
-            svc_id = lr.service_line_payment_id
-            if svc_id is None:
-                continue
-            if svc_id in used_svc_ids:
-                continue
-            svc = svc_by_id.get(svc_id)
-            cas_list = cas_by_svc.get(svc_id, [])
-            cas_total = sum((Decimal(str(c.amount)) for c in cas_list), Decimal("0"))
-            if svc:
-                paid_total += Decimal(str(svc["payment"]))
-            adjustment_total += cas_total
-            lines_out.append({
-                "claim_service_line": None,
-                "service_line_payment": svc,
-                "status": lr.status,
-                "adjustments": [
-                    {"group_code": c.group_code, "reason_code": c.reason_code,
-                     "amount": str(Decimal(str(c.amount)))}
-                    for c in cas_list
-                ],
-            })
-
-        return {
-            "claim_id": claim_id,
-            "summary": {
-                "billed_total": str(billed_total),
-                "paid_total": str(paid_total),
-                "adjustment_total": str(adjustment_total),
-                "matched_lines": matched_count,
-                "total_lines": len(claim_lines),
-            },
-            "lines": lines_out,
-        }
-
-
-def _claim_line_dict(d: dict) -> dict:
-    """Project an 837 service-line dict from ``Claim.raw_json`` to wire shape."""
-    from decimal import Decimal
-    proc = d.get("procedure") or {}
-    charge = d.get("charge")
-    units = d.get("units")
-    return {
-        "line_number": d.get("line_number"),
-        "procedure_qualifier": proc.get("qualifier", "HC"),
-        "procedure_code": proc.get("code", ""),
-        "modifiers": proc.get("modifiers") or [],
-        "charge": str(Decimal(str(charge))) if charge is not None else "0",
-        "units": str(Decimal(str(units))) if units is not None else None,
-        "unit_type": d.get("unit_type"),
-        "service_date": d.get("service_date"),
-    }
-
-
-def _svc_to_dict(svc) -> dict:
-    """Project an ORM ``ServiceLinePayment`` to wire shape."""
-    import json as _json
-    from decimal import Decimal
-    return {
-        "id": svc.id,
-        "line_number": svc.line_number,
-        "procedure_qualifier": svc.procedure_qualifier,
-        "procedure_code": svc.procedure_code,
-        "modifiers": _json.loads(svc.modifiers_json or "[]"),
-        "charge": str(Decimal(str(svc.charge))),
-        "payment": str(Decimal(str(svc.payment))),
-        "units": str(Decimal(str(svc.units))) if svc.units is not None else None,
-        "unit_type": svc.unit_type,
-        "service_date": svc.service_date.isoformat() if svc.service_date else None,
-    }
-
 
 @app.get("/api/reconciliation/unmatched")
 def get_reconciliation_unmatched() -> dict:
@@ -1708,193 +1313,11 @@ def post_reconciliation_unmatch(body: dict) -> dict:
         )
 
 
-@app.get("/api/remittances")
+# --- /api/remittances lives in cyclone.api_routers.remittances ---
-def list_remittances(
-    request: Request,
-    batch_id: str | None = Query(None),
-    payer: str | None = Query(None),
-    claim_id: str | None = Query(None),
-    date_from: str | None = Query(None),
-    date_to: str | None = Query(None),
-    sort: str | None = Query(None),
-    order: str = Query("desc"),
-    limit: int = Query(100, ge=1, le=1000),
-    offset: int = Query(0, ge=0),
-) -> Any:
-    common = dict(
-        batch_id=batch_id,
-        payer=payer,
-        claim_id=claim_id,
-        date_from=date_from,
-        date_to=date_to,
-    )
-    items = list(store.iter_remittances(
-        sort=sort, order=order, limit=limit, offset=offset, **common,
-    ))
-    total = len(list(store.iter_remittances(**common)))
-    returned = len(items)
-    has_more = total > offset + returned
-    if _wants_ndjson(request):
-        return StreamingResponse(
-            _ndjson_stream_list(items, total, returned, has_more),
-            media_type="application/x-ndjson",
-        )
-    return {
-        "items": items,
-        "total": total,
-        "returned": returned,
-        "has_more": has_more,
-    }
 
 
-@app.get("/api/remittances/stream")
-async def remittances_stream(
-    request: Request,
-    payer: str | None = Query(None),
-    claim_id: str | None = Query(None),
-    date_from: str | None = Query(None),
-    date_to: str | None = Query(None),
-    sort: str | None = Query(None),
-    order: str = Query("desc"),
-    limit: int = Query(100, ge=1, le=1000),
-) -> StreamingResponse:
-    """Stream Remittances as NDJSON: snapshot first, then live events.
-
-    Subscribes to ``remittance_written``. Default sort is
-    ``-received_date`` (newest-first), matching the list endpoint's
-    most common sort.
-
-    NOTE: registered before ``/api/remittances/{remittance_id}`` so
-    the literal ``stream`` path segment doesn't get matched as a
-    remittance id.
-    """
-    bus: EventBus = request.app.state.event_bus
-
-    async def gen() -> AsyncIterator[bytes]:
-        rows = store.iter_remittances(
-            payer=payer, claim_id=claim_id,
-            date_from=date_from, date_to=date_to,
-            sort=sort or "-received_date", order=order, limit=limit,
-        )
-        for row in rows:
-            yield _ndjson_line({"type": "item", "data": row})
-        yield _ndjson_line({"type": "snapshot_end", "data": {"count": len(rows)}})
-
-        async for chunk in _tail_events(request, bus, ["remittance_written"]):
-            yield chunk
-
-    return StreamingResponse(gen(), media_type="application/x-ndjson")
 
 
-@app.get("/api/remittances/{remittance_id}")
-def get_remittance(remittance_id: str) -> dict:
-    """Return one remittance with its labeled CAS ``adjustments`` array.
-
-    Path param is ``remittance_id`` (not ``id``) to avoid shadowing
-    FastAPI's internal ``id`` name and to keep OpenAPI docs self-
-    describing. Returns 404 when the remittance is missing — never 500.
-    """
-    body = store.get_remittance(remittance_id)
-    if body is None:
-        raise HTTPException(
-            status_code=404,
-            detail={"error": "Not found", "detail": f"Remittance {remittance_id} not found"},
-        )
-    return body
-
-
-@app.get("/api/providers")
-def list_providers(
-    request: Request,
-    npi: str | None = Query(None),
-    state: str | None = Query(None),
-    limit: int = Query(100, ge=1, le=1000),
-    offset: int = Query(0, ge=0),
-) -> Any:
-    items = store.distinct_providers()
-    if npi is not None:
-        items = [p for p in items if p["npi"] == npi]
-    if state is not None:
-        items = [p for p in items if p.get("state") == state]
-    paged = items[offset:offset + limit]
-    total = len(items)
-    returned = len(paged)
-    has_more = total > offset + returned
-    if _wants_ndjson(request):
-        return StreamingResponse(
-            _ndjson_stream_list(paged, total, returned, has_more),
-            media_type="application/x-ndjson",
-        )
-    return {
-        "items": paged,
-        "total": total,
-        "returned": returned,
-        "has_more": has_more,
-    }
-
-
-@app.get("/api/activity")
-def list_activity(
-    request: Request,
-    kind: str | None = Query(None),
-    since: str | None = Query(None),
-    limit: int = Query(200, ge=1, le=500),
-) -> Any:
-    events = store.recent_activity(limit=limit)
-    if kind is not None:
-        events = [e for e in events if e["kind"] == kind]
-    if since is not None:
-        events = [e for e in events if e["timestamp"] >= since]
-    total = len(events)
-    has_more = False
-    if _wants_ndjson(request):
-        return StreamingResponse(
-            _ndjson_stream_list(events, total, total, has_more),
-            media_type="application/x-ndjson",
-        )
-    return {
-        "items": events,
-        "total": total,
-        "returned": total,
-        "has_more": has_more,
-    }
-
-
-@app.get("/api/activity/stream")
-async def activity_stream(
-    request: Request,
-    kind: str | None = Query(None),
-    since: str | None = Query(None),
-    limit: int = Query(50, ge=1, le=500),
-) -> StreamingResponse:
-    """Stream Activity events as NDJSON: snapshot first, then live events.
-
-    Subscribes to ``activity_recorded``. Default ``limit`` is 50
-    (smaller than the list endpoint's 200) because activity is
-    high-volume — callers usually want the most recent handful, not a
-    full replay.
-    """
-    bus: EventBus = request.app.state.event_bus
-
-    async def gen() -> AsyncIterator[bytes]:
-        # Snapshot reuses the same in-memory filter as ``list_activity``
-        # so the two endpoints are interchangeable for the snapshot
-        # half.
-        events = store.recent_activity(limit=limit)
-        if kind is not None:
-            events = [e for e in events if e["kind"] == kind]
-        if since is not None:
-            events = [e for e in events if e["timestamp"] >= since]
-        for ev in events:
-            yield _ndjson_line({"type": "item", "data": ev})
-        yield _ndjson_line({
-            "type": "snapshot_end", "data": {"count": len(events)},
-        })
-
-        async for chunk in _tail_events(request, bus, ["activity_recorded"]):
-            yield chunk
-
-    return StreamingResponse(gen(), media_type="application/x-ndjson")
 
 
 # --------------------------------------------------------------------------- #
@@ -2089,125 +1512,8 @@ async def post_eligibility_parse_271(
     }
 
 
-# ---------------------------------------------------------------------------
-# SP9: providers / payers / clearhouse endpoints
-# ---------------------------------------------------------------------------
 
 
-@app.get("/api/clearhouse")
-def get_clearhouse():
-    """Return the singleton clearhouse config (dzinesco's identity, SFTP block, filename block)."""
-    ch = store.get_clearhouse()
-    if ch is None:
-        raise HTTPException(status_code=404, detail="clearhouse not seeded")
-    return json.loads(ch.model_dump_json())
-
-
-@app.post("/api/clearhouse/submit")
-def submit_to_clearhouse(body: dict):
-    """Submit a batch of claims to the clearhouse (SFTP). SP9: stub.
-
-    Body: ``{"claim_ids": [...], "payer_id": "CO_TXIX"}``
-
-    Stub behavior: serializes each claim via the SP7 serializer, builds
-    an HCPF-compliant outbound filename, and copies the result to
-    ``{staging_dir}/{outbound_path}/{filename}`` instead of opening a
-    real SFTP connection. Returns a receipt per claim.
-    """
-    from cyclone.clearhouse import make_client
-    from cyclone.edi.filenames import build_outbound_filename
-
-    claim_ids = body.get("claim_ids", [])
-    payer_id = body.get("payer_id")
-    if not claim_ids:
-        raise HTTPException(status_code=400, detail="claim_ids required")
-    if not payer_id:
-        raise HTTPException(status_code=400, detail="payer_id required")
-
-    ch = store.get_clearhouse()
-    if ch is None:
-        raise HTTPException(status_code=500, detail="clearhouse not seeded")
-
-    client = make_client(ch.sftp_block)
-    results = []
-    for cid in claim_ids:
-        try:
-            x12_text = _serialize_claim_for_submit(cid)
-        except Exception as exc:  # noqa: BLE001
-            results.append({"claim_id": cid, "ok": False, "error": str(exc)})
-            continue
-        filename = build_outbound_filename(ch.tpid, "837P")
-        remote = f"{ch.sftp_block.paths['outbound']}/{filename}"
-        staging_path = client.write_file(remote, x12_text.encode("utf-8"))
-        results.append({
-            "claim_id": cid,
-            "ok": True,
-            "filename": filename,
-            "staging_path": str(staging_path),
-            "remote_path": remote,
-        })
-        # SP11: audit trail for each successful clearhouse submission.
-        with db.SessionLocal()() as audit_s:
-            append_event(audit_s, AuditEvent(
-                event_type="clearhouse.submitted",
-                entity_type="claim",
-                entity_id=cid,
-                payload={
-                    "filename": filename,
-                    "remote_path": remote,
-                    "tpid": ch.tpid,
-                    "stub": ch.sftp_block.stub,
-                },
-                actor="clearhouse-submit",
-            ))
-            audit_s.commit()
-    return {"ok": True, "submitted": results, "stub": ch.sftp_block.stub}
-
-
-def _serialize_claim_for_submit(claim_id: str) -> str:
-    """Serialize a claim to X12 for SFTP submission. Lazy import of the
-    serializer to avoid pulling FastAPI machinery at module import time."""
-    from cyclone.parsers.serialize_837 import serialize_837
-    from cyclone import db
-    with db.SessionLocal()() as s:
-        row = s.get(db.Claim, claim_id)
-        if row is None:
-            raise ValueError(f"claim {claim_id!r} not found")
-        # Re-parse the stored raw_json to get a ClaimOutput
-        from cyclone.parsers.models import ClaimOutput, Envelope, Subscriber, Payer, BillingProvider
-        from cyclone.parsers.parse_837 import parse
-        raw = row.raw_json or {}
-        # Reconstruct minimal ClaimOutput from raw_json; this is best-effort.
-        return _serialize_claim_from_raw(row, raw)
-
-
-def _serialize_claim_from_raw(claim_row, raw: dict) -> str:
-    """Best-effort serializer that uses the stored raw_json to emit a fresh 837.
-
-    For SP9 this delegates to the existing serialize_837 helper if the
-    claim has a complete raw_segments array. Otherwise it returns a
-    minimal placeholder.
-    """
-    from cyclone.parsers.serialize_837 import serialize_837
-    from cyclone.parsers.parse_837 import parse
-
-    # Re-parse the original batch text (need to re-derive from store).
-    # SP9 stub: if the claim has a `raw_json` with `x12_text`, use that.
-    if isinstance(raw, dict) and raw.get("x12_text"):
-        result = parse(raw["x12_text"])
-        if result.claims:
-            return serialize_837(result.claims[0])
-    # Fallback: raise so the caller sees an error.
-    raise RuntimeError(
-        f"claim {claim_row.id!r} cannot be re-serialized: no stored x12_text"
-    )
-
-
-@app.get("/api/config/providers")
-def list_configured_providers(is_active: bool | None = Query(default=True)):
-    """List the configured provider rows (3 NPIs for SP9)."""
-    return [json.loads(p.model_dump_json()) for p in store.list_providers(is_active=is_active)]
-
 
 # --------------------------------------------------------------------------- #
 # SP11: tamper-evident audit log (admin)
@@ -2430,35 +1736,8 @@ def rotate_db_key_endpoint(body: dict | None = None) -> Any:
         _db_rotate_lock.release()
 
 
-@app.get("/api/config/providers/{npi}")
-def get_configured_provider(npi: str):
-    p = store.get_provider(npi)
-    if p is None:
-        raise HTTPException(status_code=404, detail=f"provider {npi!r} not found")
-    return json.loads(p.model_dump_json())
 
 
-@app.get("/api/config/payers")
-def list_configured_payers(is_active: bool | None = Query(default=True)):
-    return [json.loads(p.model_dump_json()) for p in store.list_payers(is_active=is_active)]
-
-
-@app.get("/api/config/payers/{payer_id}/configs")
-def list_payer_configs(payer_id: str):
-    """List all (transaction_type, config_json) blocks for a payer."""
-    from cyclone import payers as payer_loader
-    configs = [
-        {"transaction_type": tx, "config_json": block, "source": "yaml"}
-        for (pid, tx), block in payer_loader.all_configs().items()
-        if pid == payer_id
-    ]
-    # Also check the DB for runtime-overridden configs
-    for tx in ("837P", "835", "277CA", "999", "TA1"):
-        live = store.get_payer_config(payer_id, tx)
-        if live is not None:
-            configs.append({"transaction_type": tx, "config_json": live, "source": "db"})
-    return configs
-
 
 @app.post("/api/admin/reload-config")
 def reload_config():

backend/src/cyclone/api_routers/activity.py

@@ -0,0 +1,97 @@
+"""``/api/activity`` — list & live-tail of recorded Activity events.
+
+The Activity log is the cross-resource audit feed: every parser write,
+inbox state change, match/dismiss/resubmit, clearhouse submission, etc.
+records one row keyed by ``kind``. The list endpoint returns the most
+recent ``limit`` events with optional ``kind`` / ``since`` filters; the
+stream endpoint emits a snapshot followed by live updates from the
+``EventBus``.
+
+The default ``limit`` on the list endpoint is 200 (matches the prior
+inline behavior); the stream endpoint defaults to 50 because activity is
+high-volume — callers usually want the most recent handful, not a full
+replay.
+"""
+from __future__ import annotations
+
+from typing import Any, AsyncIterator
+
+from fastapi import APIRouter, Query, Request
+from fastapi.responses import StreamingResponse
+
+from cyclone.api_helpers import (
+    ndjson_line,
+    ndjson_stream_list,
+    tail_events,
+    wants_ndjson,
+)
+from cyclone.pubsub import EventBus
+from cyclone.store import store
+
+router = APIRouter()
+
+
+@router.get("/api/activity")
+def list_activity_endpoint(
+    request: Request,
+    kind: str | None = Query(None),
+    since: str | None = Query(None),
+    limit: int = Query(200, ge=1, le=500),
+) -> Any:
+    """Return the recent Activity log, newest first.
+
+    Optional ``kind`` filters by ``event["kind"]`` (e.g. ``claim_submitted``).
+    Optional ``since`` is an inclusive ISO timestamp lower bound applied
+    to ``event["timestamp"]``.
+    """
+    events = store.recent_activity(limit=limit)
+    if kind is not None:
+        events = [e for e in events if e["kind"] == kind]
+    if since is not None:
+        events = [e for e in events if e["timestamp"] >= since]
+    total = len(events)
+    has_more = False
+    if wants_ndjson(request):
+        return StreamingResponse(
+            ndjson_stream_list(events, total, total, has_more),
+            media_type="application/x-ndjson",
+        )
+    return {
+        "items": events,
+        "total": total,
+        "returned": total,
+        "has_more": has_more,
+    }
+
+
+@router.get("/api/activity/stream")
+async def activity_stream_endpoint(
+    request: Request,
+    kind: str | None = Query(None),
+    since: str | None = Query(None),
+    limit: int = Query(50, ge=1, le=500),
+) -> StreamingResponse:
+    """Stream Activity events as NDJSON: snapshot first, then live events.
+
+    Subscribes to ``activity_recorded``. The snapshot half reuses the
+    same in-memory filter as ``list_activity`` so the two endpoints are
+    interchangeable for the snapshot half.
+    """
+    bus: EventBus = request.app.state.event_bus
+
+    async def gen() -> AsyncIterator[bytes]:
+        events = store.recent_activity(limit=limit)
+        if kind is not None:
+            events = [e for e in events if e["kind"] == kind]
+        if since is not None:
+            events = [e for e in events if e["timestamp"] >= since]
+        for ev in events:
+            yield ndjson_line({"type": "item", "data": ev})
+        yield ndjson_line({
+            "type": "snapshot_end", "data": {"count": len(events)},
+        })
+
+        async for chunk in tail_events(request, bus, ["activity_recorded"]):
+            yield chunk
+
+    return StreamingResponse(gen(), media_type="application/x-ndjson")

backend/src/cyclone/api_routers/batches.py

@@ -0,0 +1,75 @@
+"""``/api/batches`` — list & detail endpoints for parsed batches.
+
+Each ``store.add(...)`` call (837P, 835, 999, TA1, 277CA) produces a
+``BatchRecord`` kept in memory by :class:`CycloneStore`. The list
+endpoint returns a lightweight summary (id, kind, filename, parsedAt,
+claim count) for the recent batches; the detail endpoint returns the
+full parsed payload for one batch.
+"""
+from __future__ import annotations
+
+import json
+from typing import Any
+
+from fastapi import APIRouter, HTTPException, Query, Request
+from fastapi.responses import StreamingResponse
+
+from cyclone.api_helpers import ndjson_stream_list, wants_ndjson
+from cyclone.store import BatchRecord, store
+
+router = APIRouter()
+
+
+def _batch_summary_claim_count(rec: BatchRecord) -> int:
+    """Return the number of claims on a batch, handling both 837P and 835."""
+    if rec.kind == "837p":
+        return len(rec.result.claims)  # type: ignore[attr-defined]
+    if rec.kind == "835":
+        return len(rec.result.claims)  # type: ignore[attr-defined]
+    return 0
+
+
+@router.get("/api/batches")
+def list_batches_endpoint(
+    request: Request,
+    limit: int = Query(100, ge=1, le=1000),
+) -> Any:
+    """Summary of all parsed batches, newest first."""
+    records = store.list(limit=limit)
+    items = [
+        {
+            "id": r.id,
+            "kind": r.kind,
+            "inputFilename": r.input_filename,
+            "parsedAt": r.parsed_at.isoformat().replace("+00:00", "Z"),
+            "claimCount": _batch_summary_claim_count(r),
+        }
+        for r in records
+    ]
+    all_records = store.all()
+    total = len(all_records)
+    returned = len(items)
+    has_more = total > returned
+    if wants_ndjson(request):
+        return StreamingResponse(
+            ndjson_stream_list(items, total, returned, has_more),
+            media_type="application/x-ndjson",
+        )
+    return {
+        "items": items,
+        "total": total,
+        "returned": returned,
+        "has_more": has_more,
+    }
+
+
+@router.get("/api/batches/{batch_id}")
+def get_batch_endpoint(batch_id: str) -> Any:
+    """Return the full parsed payload for one batch."""
+    rec = store.get(batch_id)
+    if rec is None:
+        raise HTTPException(
+            status_code=404,
+            detail={"error": "Not found", "detail": f"Batch {batch_id} not found"},
+        )
+    return json.loads(rec.result.model_dump_json())

backend/src/cyclone/api_routers/claims.py

@@ -0,0 +1,411 @@
+"""``/api/claims`` — list, live-tail, detail, X12 regenerate, line-reconciliation.
+
+This is the largest single-resource router. Five endpoints:
+
+* ``GET /api/claims`` — paginated list with filters
+  (status / batch_id / provider_npi / payer / date range / sort).
+* ``GET /api/claims/stream`` — NDJSON snapshot + live tail via the
+  ``claim_written`` EventBus kind.
+* ``GET /api/claims/{claim_id}`` — drawer detail
+  (header / state / service lines / diagnoses / parties / validation /
+  raw segments / stateHistory / matchedRemittance).
+* ``GET /api/claims/{claim_id}/serialize-837`` — regenerate X12 for
+  download (SP8).
+* ``GET /api/claims/{claim_id}/line-reconciliation`` — per-line
+  reconciliation view for the ClaimDrawer tab (spec §5.1).
+
+**Route ordering.** ``/stream`` is declared **before** ``/{claim_id}`` so
+FastAPI's first-match routing doesn't swallow the literal ``stream``
+segment as a claim id. Same order as the prior inline code.
+
+The two projection helpers ``_claim_line_dict`` / ``_svc_to_dict`` are
+private to this router; both only used by the line-reconciliation
+endpoint.
+"""
+from __future__ import annotations
+
+from decimal import Decimal
+from typing import Any, AsyncIterator
+
+from fastapi import APIRouter, HTTPException, Query, Request
+from fastapi.responses import JSONResponse, Response, StreamingResponse
+
+from cyclone import db
+from cyclone.api_helpers import (
+    ndjson_line,
+    ndjson_stream_list,
+    tail_events,
+    wants_ndjson,
+)
+from cyclone.db import Claim
+from cyclone.parsers.models import ClaimOutput
+from cyclone.parsers.serialize_837 import SerializeError as SerializeError837, serialize_837
+from cyclone.pubsub import EventBus
+from cyclone.store import store
+
+router = APIRouter()
+
+
+@router.get("/api/claims")
+def list_claims_endpoint(
+    request: Request,
+    batch_id: str | None = Query(None),
+    status: str | None = Query(None),
+    provider_npi: str | None = Query(None),
+    payer: str | None = Query(None),
+    date_from: str | None = Query(None),
+    date_to: str | None = Query(None),
+    sort: str | None = Query(None),
+    order: str = Query("desc"),
+    limit: int = Query(100, ge=1, le=1000),
+    offset: int = Query(0, ge=0),
+) -> Any:
+    """Paginated claims list with filters; supports NDJSON streaming.
+
+    ``has_more`` is computed as ``total > offset + returned`` so paginating
+    forward keeps returning true until the last page is reached.
+    """
+    common = dict(
+        batch_id=batch_id,
+        status=status,
+        provider_npi=provider_npi,
+        payer=payer,
+        date_from=date_from,
+        date_to=date_to,
+    )
+    items = list(store.iter_claims(
+        sort=sort, order=order, limit=limit, offset=offset, **common,
+    ))
+    total = len(list(store.iter_claims(**common)))
+    returned = len(items)
+    has_more = total > offset + returned
+    if wants_ndjson(request):
+        return StreamingResponse(
+            ndjson_stream_list(items, total, returned, has_more),
+            media_type="application/x-ndjson",
+        )
+    return {
+        "items": items,
+        "total": total,
+        "returned": returned,
+        "has_more": has_more,
+    }
+
+
+@router.get("/api/claims/stream")
+async def claims_stream_endpoint(
+    request: Request,
+    status: str | None = Query(None),
+    provider_npi: str | None = Query(None),
+    payer: str | None = Query(None),
+    date_from: str | None = Query(None),
+    date_to: str | None = Query(None),
+    sort: str | None = Query(None),
+    order: str = Query("desc"),
+    limit: int = Query(100, ge=1, le=1000),
+) -> StreamingResponse:
+    """Stream Claims as NDJSON: snapshot first, then live events.
+
+    Wire format:
+      * ``{"type":"item","data":<claim>}`` per snapshot row, then per
+        new ``claim_written`` event
+      * ``{"type":"snapshot_end","data":{"count":N}}`` after the snapshot
+      * ``{"type":"heartbeat","data":{"ts":<iso>}}`` every
+        ``CYCLONE_TAIL_HEARTBEAT_S`` seconds when idle
+
+    Query params mirror :func:`list_claims_endpoint` so a frontend can
+    swap a one-shot fetch for a tail with no URL surgery.
+
+    NOTE: registered before ``/api/claims/{claim_id}`` so the literal
+    ``stream`` path segment doesn't get matched as a claim id.
+    """
+    bus: EventBus = request.app.state.event_bus
+
+    async def gen() -> AsyncIterator[bytes]:
+        # 1. Snapshot (eager — iter_claims returns a list already).
+        rows = store.iter_claims(
+            status=status, provider_npi=provider_npi, payer=payer,
+            date_from=date_from, date_to=date_to,
+            sort=sort or "-submission_date", order=order, limit=limit,
+        )
+        for row in rows:
+            yield ndjson_line({"type": "item", "data": row})
+        yield ndjson_line({"type": "snapshot_end", "data": {"count": len(rows)}})
+
+        # 2. Subscribe + heartbeats.
+        async for chunk in tail_events(request, bus, ["claim_written"]):
+            yield chunk
+
+    return StreamingResponse(gen(), media_type="application/x-ndjson")
+
+
+@router.get("/api/claims/{claim_id}")
+def get_claim_detail_endpoint(claim_id: str) -> dict:
+    """Return one claim with full drawer context (SP4).
+
+    Body shape is produced by :meth:`CycloneStore.get_claim_detail`:
+    header, state, service lines, diagnoses, parties, validation,
+    raw segments, ``stateHistory`` (most-recent-first, capped at 50),
+    and a populated ``matchedRemittance`` block when paired.
+
+    Returns 404 — never 500 — on a missing claim so the UI can
+    distinguish "doesn't exist" from a transient fetch error.
+    """
+    body = store.get_claim_detail(claim_id)
+    if body is None:
+        raise HTTPException(
+            status_code=404,
+            detail={
+                "error": "Not found",
+                "detail": f"Claim {claim_id} not found",
+            },
+        )
+    return body
+
+
+@router.get("/api/claims/{claim_id}/serialize-837")
+def serialize_claim_as_837(claim_id: str):
+    """Return the claim as a regenerated X12 837P file (SP8).
+
+    Loads the ClaimOutput from the persisted ``raw_json`` and runs the
+    outbound serializer. Returns 404 if the claim doesn't exist, 422 if
+    the stored payload has no parseable ClaimOutput (data integrity
+    issue, not a transient failure).
+    """
+    with db.SessionLocal()() as s:
+        row = s.get(Claim, claim_id)
+        if row is None:
+            return JSONResponse(
+                {"error": "Not found", "detail": f"Claim {claim_id} not found"},
+                status_code=404,
+            )
+        if not row.raw_json:
+            return JSONResponse(
+                {
+                    "error": "Unprocessable",
+                    "detail": f"Claim {claim_id} has no raw_json; cannot serialize",
+                },
+                status_code=422,
+            )
+        try:
+            claim_obj = ClaimOutput.model_validate(row.raw_json)
+        except Exception as exc:
+            return JSONResponse(
+                {
+                    "error": "Unprocessable",
+                    "detail": f"Claim {claim_id} raw_json is malformed: {exc}",
+                },
+                status_code=422,
+            )
+
+    try:
+        text = serialize_837(claim_obj)
+    except SerializeError837 as exc:
+        return JSONResponse(
+            {"error": "Unprocessable", "detail": str(exc)},
+            status_code=422,
+        )
+
+    return Response(
+        content=text,
+        media_type="text/x12",
+        headers={
+            "Content-Disposition": f'attachment; filename="claim-{claim_id}.x12"'
+        },
+    )
+
+
+@router.get("/api/claims/{claim_id}/line-reconciliation")
+def get_claim_line_reconciliation(claim_id: str) -> dict:
+    """Per-line reconciliation view for the ClaimDrawer tab.
+
+    Spec §5.1. Returns the 837 service lines and 835 SVC composites
+    side-by-side, with per-line CAS adjustments and a summary block.
+
+    Architecture note: 837 service lines live in ``Claim.raw_json``
+    (not a separate ORM table), so the 837-side rows are read from the
+    JSON blob; the 835-side rows come from ``ServiceLinePayment`` ORM.
+    ``LineReconciliation.claim_service_line_number`` stores the 1-based
+    line number to join them.
+    """
+    from sqlalchemy import select
+
+    from cyclone.db import (
+        CasAdjustment,
+        LineReconciliation,
+        ServiceLinePayment,
+    )
+
+    with db.SessionLocal()() as s:
+        claim = s.get(db.Claim, claim_id)
+        if claim is None:
+            raise HTTPException(
+                status_code=404,
+                detail={"error": "Not found", "detail": f"Claim {claim_id} not found"},
+            )
+
+        # 837 service lines: from raw_json.
+        raw = claim.raw_json or {}
+        claim_lines_raw = raw.get("service_lines") or []
+        # Normalize to dicts for the response.
+        claim_lines = [_claim_line_dict(d) for d in claim_lines_raw]
+
+        # 835 service payments: ORM rows from the matched remit.
+        remits = list(
+            s.execute(
+                select(db.Remittance).where(db.Remittance.claim_id == claim_id)
+            ).scalars().all()
+        )
+        svc_payments: list[dict] = []
+        svc_ids: list[int] = []
+        if remits:
+            svc_rows = list(
+                s.execute(
+                    select(ServiceLinePayment).where(
+                        ServiceLinePayment.remittance_id.in_([r.id for r in remits])
+                    ).order_by(ServiceLinePayment.line_number)
+                ).scalars().all()
+            )
+            for svc in svc_rows:
+                d = _svc_to_dict(svc)
+                svc_payments.append(d)
+                svc_ids.append(svc.id)
+
+        # LineReconciliation rows.
+        lrs = list(
+            s.execute(
+                select(LineReconciliation).where(LineReconciliation.claim_id == claim_id)
+            ).scalars().all()
+        )
+        # Index by claim_service_line_number and service_line_payment_id.
+        lr_by_claim_num: dict[int, LineReconciliation] = {
+            lr.claim_service_line_number: lr for lr in lrs if lr.claim_service_line_number is not None
+        }
+        lr_by_svc: dict[int, LineReconciliation] = {
+            lr.service_line_payment_id: lr for lr in lrs if lr.service_line_payment_id is not None
+        }
+
+        # CAS rows grouped by svc id.
+        cas_by_svc: dict[int, list[CasAdjustment]] = {}
+        if svc_ids:
+            cas_rows = list(
+                s.execute(
+                    select(CasAdjustment).where(CasAdjustment.service_line_payment_id.in_(svc_ids))
+                ).scalars().all()
+            )
+            for c in cas_rows:
+                cas_by_svc.setdefault(c.service_line_payment_id, []).append(c)
+
+        # Build output lines array, preserving 837 order then 835-only.
+        svc_by_id: dict[int, dict] = {d["id"]: d for d in svc_payments}
+        lines_out: list[dict] = []
+        billed_total = Decimal("0")
+        paid_total = Decimal("0")
+        adjustment_total = Decimal("0")
+        matched_count = 0
+        used_svc_ids: set[int] = set()
+
+        for cl in claim_lines:
+            billed_total += Decimal(str(cl["charge"]))
+            lr = lr_by_claim_num.get(cl["line_number"])
+            if lr is None:
+                lines_out.append({
+                    "claim_service_line": cl,
+                    "service_line_payment": None,
+                    "status": "unmatched_837_only",
+                    "adjustments": [],
+                })
+                continue
+            svc_id = lr.service_line_payment_id
+            svc = svc_by_id.get(svc_id) if svc_id else None
+            if svc_id is not None:
+                used_svc_ids.add(svc_id)
+            cas_list = cas_by_svc.get(svc_id, []) if svc_id is not None else []
+            cas_total = sum((Decimal(str(c.amount)) for c in cas_list), Decimal("0"))
+            if svc:
+                paid_total += Decimal(str(svc["payment"]))
+            adjustment_total += cas_total
+            if lr.status == "matched":
+                matched_count += 1
+            lines_out.append({
+                "claim_service_line": cl,
+                "service_line_payment": svc,
+                "status": lr.status,
+                "adjustments": [
+                    {"group_code": c.group_code, "reason_code": c.reason_code,
+                     "amount": str(Decimal(str(c.amount)))}
+                    for c in cas_list
+                ],
+            })
+
+        # 835-only lines (no claim match).
+        for lr in lrs:
+            if lr.claim_service_line_number is not None:
+                continue
+            svc_id = lr.service_line_payment_id
+            if svc_id is None:
+                continue
+            if svc_id in used_svc_ids:
+                continue
+            svc = svc_by_id.get(svc_id)
+            cas_list = cas_by_svc.get(svc_id, [])
+            cas_total = sum((Decimal(str(c.amount)) for c in cas_list), Decimal("0"))
+            if svc:
+                paid_total += Decimal(str(svc["payment"]))
+            adjustment_total += cas_total
+            lines_out.append({
+                "claim_service_line": None,
+                "service_line_payment": svc,
+                "status": lr.status,
+                "adjustments": [
+                    {"group_code": c.group_code, "reason_code": c.reason_code,
+                     "amount": str(Decimal(str(c.amount)))}
+                    for c in cas_list
+                ],
+            })
+
+        return {
+            "claim_id": claim_id,
+            "summary": {
+                "billed_total": str(billed_total),
+                "paid_total": str(paid_total),
+                "adjustment_total": str(adjustment_total),
+                "matched_lines": matched_count,
+                "total_lines": len(claim_lines),
+            },
+            "lines": lines_out,
+        }
+
+
+def _claim_line_dict(d: dict) -> dict:
+    """Project an 837 service-line dict from ``Claim.raw_json`` to wire shape."""
+    proc = d.get("procedure") or {}
+    charge = d.get("charge")
+    units = d.get("units")
+    return {
+        "line_number": d.get("line_number"),
+        "procedure_qualifier": proc.get("qualifier", "HC"),
+        "procedure_code": proc.get("code", ""),
+        "modifiers": proc.get("modifiers") or [],
+        "charge": str(Decimal(str(charge))) if charge is not None else "0",
+        "units": str(Decimal(str(units))) if units is not None else None,
+        "unit_type": d.get("unit_type"),
+        "service_date": d.get("service_date"),
+    }
+
+
+def _svc_to_dict(svc) -> dict:
+    """Project an ORM ``ServiceLinePayment`` to wire shape."""
+    import json as _json
+    return {
+        "id": svc.id,
+        "line_number": svc.line_number,
+        "procedure_qualifier": svc.procedure_qualifier,
+        "procedure_code": svc.procedure_code,
+        "modifiers": _json.loads(svc.modifiers_json or "[]"),
+        "charge": str(Decimal(str(svc.charge))),
+        "payment": str(Decimal(str(svc.payment))),
+        "units": str(Decimal(str(svc.units))) if svc.units is not None else None,
+        "unit_type": svc.unit_type,
+        "service_date": svc.service_date.isoformat() if svc.service_date else None,
+    }

backend/src/cyclone/api_routers/clearhouse.py

@@ -0,0 +1,126 @@
+"""``/api/clearhouse`` — SP9 single-payer SFTP submit surface.
+
+Two endpoints:
+- ``GET /api/clearhouse`` — return the singleton clearhouse config
+  (dzinesco's identity, SFTP block, filename block). 404 when the
+  config hasn't been seeded yet.
+- ``POST /api/clearhouse/submit`` — submit a batch of claims to the
+  clearhouse (SFTP). SP9 ships a stub that copies to ``staging_dir``
+  instead of opening a real SFTP connection; SP13 wires the real
+  paramiko-backed client behind the same ``make_client()`` factory.
+
+For each claim the endpoint serializes a fresh 837 via
+:func:`_serialize_claim_for_submit`, builds an HCPF-compliant outbound
+filename, and records an audit-log row on success. Failures are
+captured per-claim so the operator sees exactly which claim_ids
+didn't go through.
+"""
+from __future__ import annotations
+
+import json
+
+from fastapi import APIRouter, HTTPException
+
+from cyclone import db
+from cyclone.audit_log import AuditEvent, append_event
+from cyclone.parsers.parse_837 import parse
+from cyclone.parsers.serialize_837 import serialize_837
+from cyclone.store import store
+
+router = APIRouter()
+
+
+@router.get("/api/clearhouse")
+def get_clearhouse():
+    """Return the singleton clearhouse config (dzinesco's identity, SFTP block, filename block)."""
+    ch = store.get_clearhouse()
+    if ch is None:
+        raise HTTPException(status_code=404, detail="clearhouse not seeded")
+    return json.loads(ch.model_dump_json())
+
+
+@router.post("/api/clearhouse/submit")
+def submit_to_clearhouse(body: dict):
+    """Submit a batch of claims to the clearhouse (SFTP). SP9: stub.
+
+    Body: ``{"claim_ids": [...], "payer_id": "CO_TXIX"}``
+
+    Stub behavior: serializes each claim via the SP7 serializer, builds
+    an HCPF-compliant outbound filename, and copies the result to
+    ``{staging_dir}/{outbound_path}/{filename}`` instead of opening a
+    real SFTP connection. Returns a receipt per claim.
+    """
+    from cyclone.clearhouse import make_client
+    from cyclone.edi.filenames import build_outbound_filename
+
+    claim_ids = body.get("claim_ids", [])
+    payer_id = body.get("payer_id")
+    if not claim_ids:
+        raise HTTPException(status_code=400, detail="claim_ids required")
+    if not payer_id:
+        raise HTTPException(status_code=400, detail="payer_id required")
+
+    ch = store.get_clearhouse()
+    if ch is None:
+        raise HTTPException(status_code=500, detail="clearhouse not seeded")
+
+    client = make_client(ch.sftp_block)
+    results = []
+    for cid in claim_ids:
+        try:
+            x12_text = _serialize_claim_for_submit(cid)
+        except Exception as exc:  # noqa: BLE001
+            results.append({"claim_id": cid, "ok": False, "error": str(exc)})
+            continue
+        filename = build_outbound_filename(ch.tpid, "837P")
+        remote = f"{ch.sftp_block.paths['outbound']}/{filename}"
+        staging_path = client.write_file(remote, x12_text.encode("utf-8"))
+        results.append({
+            "claim_id": cid,
+            "ok": True,
+            "filename": filename,
+            "staging_path": str(staging_path),
+            "remote_path": remote,
+        })
+        # SP11: audit trail for each successful clearhouse submission.
+        with db.SessionLocal()() as audit_s:
+            append_event(audit_s, AuditEvent(
+                event_type="clearhouse.submitted",
+                entity_type="claim",
+                entity_id=cid,
+                payload={
+                    "filename": filename,
+                    "remote_path": remote,
+                    "tpid": ch.tpid,
+                    "stub": ch.sftp_block.stub,
+                },
+                actor="clearhouse-submit",
+            ))
+            audit_s.commit()
+    return {"ok": True, "submitted": results, "stub": ch.sftp_block.stub}
+
+
+def _serialize_claim_for_submit(claim_id: str) -> str:
+    """Serialize a claim to X12 for SFTP submission."""
+    with db.SessionLocal()() as s:
+        row = s.get(db.Claim, claim_id)
+        if row is None:
+            raise ValueError(f"claim {claim_id!r} not found")
+        raw = row.raw_json or {}
+        return _serialize_claim_from_raw(row, raw)
+
+
+def _serialize_claim_from_raw(claim_row, raw: dict) -> str:
+    """Best-effort serializer that uses the stored raw_json to emit a fresh 837.
+
+    For SP9 this delegates to the existing serialize_837 helper if the
+    claim has a complete raw_segments array. Otherwise it raises.
+    """
+    # SP9 stub: if the claim has a `raw_json` with `x12_text`, use that.
+    if isinstance(raw, dict) and raw.get("x12_text"):
+        result = parse(raw["x12_text"])
+        if result.claims:
+            return serialize_837(result.claims[0])
+    raise RuntimeError(
+        f"claim {claim_row.id!r} cannot be re-serialized: no stored x12_text"
+    )

backend/src/cyclone/api_routers/config.py

@@ -0,0 +1,56 @@
+"""``/api/config/*`` — configured-provider / configured-payer lookups.
+
+The ``config`` prefix is the operator-facing read-only window into the
+``config/payers.yaml`` static config and the seeded providers table.
+Used by the frontend Settings page to show what's available.
+
+The payers endpoint at ``/api/config/payers/{payer_id}/configs`` is
+slightly different: it returns both the YAML-loaded config and any
+DB-overridden config (so a runtime override wins over the static
+fallback). 404 / 200 / array shape match the rest of the API.
+"""
+from __future__ import annotations
+
+import json
+
+from fastapi import APIRouter, HTTPException, Query
+
+from cyclone import payers as payer_loader
+from cyclone.store import store
+
+router = APIRouter()
+
+
+@router.get("/api/config/providers")
+def list_configured_providers(is_active: bool | None = Query(default=True)):
+    """List the configured provider rows (3 NPIs for SP9)."""
+    return [json.loads(p.model_dump_json()) for p in store.list_providers(is_active=is_active)]
+
+
+@router.get("/api/config/providers/{npi}")
+def get_configured_provider(npi: str):
+    p = store.get_provider(npi)
+    if p is None:
+        raise HTTPException(status_code=404, detail=f"provider {npi!r} not found")
+    return json.loads(p.model_dump_json())
+
+
+@router.get("/api/config/payers")
+def list_configured_payers(is_active: bool | None = Query(default=True)):
+    return [json.loads(p.model_dump_json()) for p in store.list_payers(is_active=is_active)]
+
+
+@router.get("/api/config/payers/{payer_id}/configs")
+def list_payer_configs(payer_id: str):
+    """List all (transaction_type, config_json) blocks for a payer."""
+    configs = [
+        {"transaction_type": tx, "config_json": block, "source": "yaml"}
+        for (pid, tx), block in payer_loader.all_configs().items()
+        if pid == payer_id
+    ]
+    # Also check the DB for runtime-overridden configs
+    for tx in ("837P", "835", "277CA", "999", "TA1"):
+        live = store.get_payer_config(payer_id, tx)
+        if live is not None:
+            configs.append({"transaction_type": tx, "config_json": live, "source": "db"})
+    return configs

backend/src/cyclone/api_routers/providers.py

@@ -0,0 +1,49 @@
+"""``GET /api/providers`` — distinct providers observed across claims.
+
+The list is built by ``store.distinct_providers()`` which scans claim
+rows and returns one entry per unique ``billing_provider_npi``. The
+``npi`` and ``state`` query params filter client-side. ``limit`` /
+``offset`` paginate. Accepts ``application/x-ndjson`` like the other
+list endpoints — see ``api_helpers.ndjson_stream_list``.
+"""
+from __future__ import annotations
+
+from typing import Any
+
+from fastapi import APIRouter, Query, Request
+from fastapi.responses import StreamingResponse
+
+from cyclone.api_helpers import ndjson_stream_list, wants_ndjson
+from cyclone.store import store
+
+router = APIRouter()
+
+
+@router.get("/api/providers")
+def list_providers(
+    request: Request,
+    npi: str | None = Query(None),
+    state: str | None = Query(None),
+    limit: int = Query(100, ge=1, le=1000),
+    offset: int = Query(0, ge=0),
+) -> Any:
+    items = store.distinct_providers()
+    if npi is not None:
+        items = [p for p in items if p["npi"] == npi]
+    if state is not None:
+        items = [p for p in items if p.get("state") == state]
+    paged = items[offset:offset + limit]
+    total = len(items)
+    returned = len(paged)
+    has_more = total > offset + returned
+    if wants_ndjson(request):
+        return StreamingResponse(
+            ndjson_stream_list(paged, total, returned, has_more),
+            media_type="application/x-ndjson",
+        )
+    return {
+        "items": paged,
+        "total": total,
+        "returned": returned,
+        "has_more": has_more,
+    }

backend/src/cyclone/api_routers/remittances.py

@@ -0,0 +1,130 @@
+"""``/api/remittances`` — list, live-tail, detail endpoints for 835 ERAs.
+
+Mirror of the ``claims`` router for the 835 / Remittance resource:
+
+* ``GET /api/remittances`` — paginated list with filters
+  (batch_id / payer / claim_id / date range / sort).
+* ``GET /api/remittances/stream`` — NDJSON snapshot + live tail via the
+  ``remittance_written`` EventBus kind.
+* ``GET /api/remittances/{remittance_id}`` — detail with the labeled
+  CAS ``adjustments`` array.
+
+**Route ordering.** ``/stream`` is declared **before** ``/{remittance_id}``
+so FastAPI's first-match routing doesn't swallow the literal ``stream``
+segment as a remittance id. Same order as the prior inline code.
+"""
+from __future__ import annotations
+
+from typing import Any, AsyncIterator
+
+from fastapi import APIRouter, HTTPException, Query, Request
+from fastapi.responses import StreamingResponse
+
+from cyclone.api_helpers import (
+    ndjson_line,
+    ndjson_stream_list,
+    tail_events,
+    wants_ndjson,
+)
+from cyclone.pubsub import EventBus
+from cyclone.store import store
+
+router = APIRouter()
+
+
+@router.get("/api/remittances")
+def list_remittances_endpoint(
+    request: Request,
+    batch_id: str | None = Query(None),
+    payer: str | None = Query(None),
+    claim_id: str | None = Query(None),
+    date_from: str | None = Query(None),
+    date_to: str | None = Query(None),
+    sort: str | None = Query(None),
+    order: str = Query("desc"),
+    limit: int = Query(100, ge=1, le=1000),
+    offset: int = Query(0, ge=0),
+) -> Any:
+    """Paginated remittances list with filters; supports NDJSON streaming.
+
+    ``has_more`` is computed as ``total > offset + returned`` so paginating
+    forward keeps returning true until the last page is reached.
+    """
+    common = dict(
+        batch_id=batch_id,
+        payer=payer,
+        claim_id=claim_id,
+        date_from=date_from,
+        date_to=date_to,
+    )
+    items = list(store.iter_remittances(
+        sort=sort, order=order, limit=limit, offset=offset, **common,
+    ))
+    total = len(list(store.iter_remittances(**common)))
+    returned = len(items)
+    has_more = total > offset + returned
+    if wants_ndjson(request):
+        return StreamingResponse(
+            ndjson_stream_list(items, total, returned, has_more),
+            media_type="application/x-ndjson",
+        )
+    return {
+        "items": items,
+        "total": total,
+        "returned": returned,
+        "has_more": has_more,
+    }
+
+
+@router.get("/api/remittances/stream")
+async def remittances_stream_endpoint(
+    request: Request,
+    payer: str | None = Query(None),
+    claim_id: str | None = Query(None),
+    date_from: str | None = Query(None),
+    date_to: str | None = Query(None),
+    sort: str | None = Query(None),
+    order: str = Query("desc"),
+    limit: int = Query(100, ge=1, le=1000),
+) -> StreamingResponse:
+    """Stream Remittances as NDJSON: snapshot first, then live events.
+
+    Subscribes to ``remittance_written``. Default sort is
+    ``-received_date`` (newest-first), matching the list endpoint's
+    most common sort.
+
+    NOTE: registered before ``/api/remittances/{remittance_id}`` so
+    the literal ``stream`` path segment doesn't get matched as a
+    remittance id.
+    """
+    bus: EventBus = request.app.state.event_bus
+
+    async def gen() -> AsyncIterator[bytes]:
+        rows = store.iter_remittances(
+            payer=payer, claim_id=claim_id,
+            date_from=date_from, date_to=date_to,
+            sort=sort or "-received_date", order=order, limit=limit,
+        )
+        for row in rows:
+            yield ndjson_line({"type": "item", "data": row})
+        yield ndjson_line({"type": "snapshot_end", "data": {"count": len(rows)}})
+
+        async for chunk in tail_events(request, bus, ["remittance_written"]):
+            yield chunk
+
+    return StreamingResponse(gen(), media_type="application/x-ndjson")
+
+
+@router.get("/api/remittances/{remittance_id}")
+def get_remittance_endpoint(remittance_id: str) -> dict:
+    """Return one remittance with its labeled CAS ``adjustments`` array.
+
+    Returns 404 when the remittance is missing — never 500.
+    """
+    body = store.get_remittance(remittance_id)
+    if body is None:
+        raise HTTPException(
+            status_code=404,
+            detail={"error": "Not found", "detail": f"Remittance {remittance_id} not found"},
+        )
+    return body