fix(codegen-ts): keep reverse @via view columns and refuse value-object aggregates

.nm-triage-nonprod

@@ -0,0 +1,11 @@
+# Paths that no-mistakes triage counts as non-production (one glob per line).
+# Conformance corpora and other test fixtures: data, gated by every port's runner.
+fixtures/**
+# The metamodel spec and the copies generated from it into each port.
+spec/metamodel/*.json
+server/csharp/MetaObjects/SpecMetamodel/*.json
+server/python/src/metaobjects/spec_metamodel/*.json
+server/typescript/packages/metadata/src/**/*.embedded.ts
+# The generated reference site and showcase payload.
+site-reference/**
+examples/showcase/site-payload.json

AGENTS.md

@@ -71,7 +71,7 @@ PyPI has had no product change since `0.25.0` — nothing is broken.
 - **Kotlin** — `codegen-kotlin` (KotlinPoet on JVM): entity + Exposed table + Spring controller + payload + relations + filter allowlist + validator + stored-proc + output-parser generators. `integration-tests-kotlin` runs the persistence-conformance corpus through Exposed against Testcontainers Postgres.
 
 **Cross-port conformance corpora** (every port runs the shared corpus):
-- Metamodel: `fixtures/conformance/` (458 fixtures; 38 shared corpora in total — per-corpus counts + the corpus x port matrix live in `docs/CONFORMANCE.md`). TS / C# / Java / Python all green.
+- Metamodel: `fixtures/conformance/` (459 fixtures; 38 shared corpora in total — per-corpus counts + the corpus x port matrix live in `docs/CONFORMANCE.md`). TS / C# / Java / Python all green.
 - Render: `fixtures/render-conformance/`. TS / C# / Java / Kotlin / Python byte-identical.
 - Persistence: `fixtures/persistence-conformance/`. **Query** scenarios run on every port (TS / C# / Java / Kotlin / Python), each provisioning its test DB by executing the committed, TS-produced `canonical/schema.postgres.sql` (Postgres only — Derby dropped for the cross-port query corpus, ADR-0015; the FR-044 `report-*` scenarios also run on SQLite, MySQL and D1 where a port has the engine, see [docs/CONFORMANCE.md](docs/CONFORMANCE.md)). The **migration** scenarios are exercised by **TS only** (TS owns schema migrations). **The corpus now gates WRITES, not just reads (SP-H):** an `op: roundtrip` scenario type INSERTs through each port's runtime/ORM write codec (NOT raw SQL), reads the row back, and asserts the wire-normalized value. The `AllTypes` entity (`roundtrip-all-types.yaml`) carries one field of **every** persistable `field.*` subtype — string/int/long/double/float/decimal/boolean/date/time/timestamp(+tz)/currency/enum/uuid/object — plus an **array-of-VO** `field.object @isArray @storage:jsonb` column (`labels`, written as 2-element / empty-`[]` / single-element arrays across the three rows) — so every subtype write+read (incl. the array-of-value-object jsonb codec) round-trips through every port against Testcontainers PG. (`field.byte`/`field.short`/`field.class` were cut as non-functional registration-only stubs — the matrix tracks only genuinely-supported subtypes; see `fixtures/registry-conformance/README.md` → "Per-subtype write-round-trip matrix".)
 - API-contract: `fixtures/api-contract-conformance/`. TS / C# / Java / Kotlin / Python all green — each port runs **two lanes**: a hand-rolled reference server AND its **generated** API artifact booted over HTTP (the deployed controller/routes; TS+C# full-stack vs Testcontainers PG, Java/Kotlin/Python generated controller + in-memory repo behind the consumer seam). The generated fan-out found 10 real deployment bugs golden snapshots missed. Three sub-corpora run the **generated lane only, on all five ports** — `write-through/`, `projection/` (F22: a view-only `object.projection` serves GET list + GET by id and answers every write verb with `405 {"error": "method_not_allowed"}`) and `report/` (FR-044: a view-backed `object.report` serves GET list, answers `POST` with that same `405`, and mounts no `/{id}` route). That is deliberate, not a gap: what is under test is whether a port's GENERATOR emits those routes, and a hand-rolled reference server would answer every scenario by construction. The `m2m/` sub-corpus also gates **TPH x M:N together** (base-declared, subtype-declared, abstract-mid-declared, a non-subtype source onto a subtype TARGET, and the cross-subtype source id answering `200 []`) — the two corpora were originally built disjoint (`tph/` had no relationships, `m2m/` no discriminators), which is precisely how that defect class survived.

CHANGELOG.md

@@ -10,6 +10,27 @@ here.**
 
 ## [Unreleased]
 
+### Fixed
+
+- **A projection view keeps the columns a reverse `@via` hop feeds.** An origin `@via` that walks
+  an `identity.reference` backwards (`Project.timeEntries`, #560) loaded, but `meta migrate` left
+  its `origin.aggregate` / `origin.first` columns out of `CREATE VIEW` without a word. The view
+  emitter now resolves the hop the way the loader does and joins from the holder of the
+  reference. Gated by a Postgres test that creates the view and reads it.
+- **`origin.aggregate` `sum`/`avg`/`min`/`max` over a value-object field is refused at load.**
+  `@of: Invoice.total` on a flattened Money field loaded and emitted `SUM(i.total)`, a column that
+  does not exist. Every port now refuses it with `ERR_INVALID_ORIGIN` and says to aggregate a
+  scalar field; gated by the `error-origin-aggregate-value-object` conformance fixture. Refusing,
+  rather than summing the flattened amount column, keeps a sum from adding amounts in different
+  currencies. `count` is unaffected.
+
+### Changed
+
+- **Agent context routes report work to the reporting vocabulary.** The `meta init` agent guide
+  and the `metaobjects-authoring` skill now send grouped totals, dashboard numbers and read-only
+  report views to `object.report` (`references/declaring-reports.md`) before the `@sql` escape,
+  which they describe as the last resort for bodies the vocabulary cannot express.
+
 ## [1.3.0] — 2026-11-11
 
 _npm `1.3.0` (full lockstep across all 14 `@metaobjectsdev/*` publish candidates)._

agent-context/skills/metaobjects-authoring/SKILL.md

@@ -31,10 +31,10 @@ This file covers what almost every model needs. The topics below live in
 | `references/identities-and-indexes.md` | declaring a primary, secondary or reference identity, an FK, or a non-unique `index.lookup` |
 | `references/sources.md` | the `source.rdb` shape and `@kind`; a store MetaObjects does not manage; a derived or computed column (reach for an entity read-view first) |
 | `references/abstracts-and-overlay.md` | a shared `abstract` base, `extends`, or a layered `overlay` file |
-| `references/declaring-reports.md` | declaring `dimension.*`, `measure.*`, `segment.filter` or an `object.report` |
+| `references/declaring-reports.md` | **open first** for a report, dashboard, totals, `GROUP BY`, "per client / per month" or a read-only summary view: declaring `dimension.*`, `measure.*`, `segment.filter` or an `object.report` |
 | `references/model-first-rationale.md` | someone argues that hand-writing a layer is cheaper this once |
 | `references/relationships.md` | a many-to-many link or self-join, or a "rows that reference this one" query |
-| `references/read-views-and-projections.md` | an `object.projection`, `origin.*` vocabulary, `@filter` / `@expr`, or an `@sql` / `@unmanaged` view |
+| `references/read-views-and-projections.md` | an `object.projection`, `origin.*` vocabulary, `@filter` / `@expr`, or an `@sql` / `@unmanaged` view (a grouped or aggregate view is `declaring-reports.md` first) |
 | `references/inheritance-tph.md` | several entities are variants of one thing sharing a single table (`@discriminator`) |
 | `references/metadata-dependencies.md` | the project builds on another package's metadata (`dependencies`, cross-package `overlay`) |
 | `references/reporting.md` | what a declared report gives you: what columns a report gets, time grains, null rules, rows with no facts (`@spine`), defaults (`@default`), engine differences |

agent-context/skills/metaobjects-authoring/references/read-views-and-projections.md

@@ -1,6 +1,6 @@
 # Projections, `origin.*`, and managed views
 
-> Part of the `metaobjects-authoring` skill. The skill covers the entity read-view, which is the right answer for most grids. Read this when you need an independent exposure (`object.projection`), the `origin.*` vocabulary, `@filter` / `@expr` shapes, or an `@sql` / `@unmanaged` view.
+> Part of the `metaobjects-authoring` skill. The skill covers the entity read-view, which is the right answer for most grids. Read this when you need an independent exposure (`object.projection`), the `origin.*` vocabulary, `@filter` / `@expr` shapes, or an `@sql` / `@unmanaged` view. A grouped total or report (per client, per month) is an `object.report`: `declaring-reports.md`.
 
 ## Contents
 - Read-view or projection?
@@ -125,8 +125,9 @@ non-aggregate-derived** projection fields: naming an undeclared field fails the
 
 **The `CREATE VIEW` body is generated from those `origin.*` children by the Node
 `meta migrate` — never hand-author view SQL for a shape origins can express** (an unmodeled
-view is *unmanaged*, so `meta verify --db` can't even catch the drift). For a genuinely
-irreducible body (recursive CTE, window function, set operation) that origins can't express,
+view is *unmanaged*, so `meta verify --db` can't even catch the drift). **An `@sql` body that
+`GROUP BY`s: check `declaring-reports.md` first** (`object.report`, `@spine`, `@default`).
+For a genuinely irreducible body (recursive CTE, window function, set operation) that origins can't express,
 carry it in the `source.rdb` **`@sql`** escape (#208, ADR-0043) — a hand-written body the
 tool registers, fingerprints, and drift-checks (adopt a pre-existing view with
 `meta migrate --allow adopt-view`) — rather than a hand-edited migration file where it goes

agent-context/skills/metaobjects-authoring/references/sources.md

@@ -94,4 +94,6 @@ column because the filter tier runs against the view.
 **When you need an independent exposure** — a subset, renamed columns, a row-filtered
 view, a versioned or external shape — that is an `object.projection`. It, the `origin.*`
 vocabulary, the structured `@filter` / `@expr` shapes and the `@sql` / `@unmanaged` escapes
-are in `references/read-views-and-projections.md`.
+are in `references/read-views-and-projections.md`. A grouped or aggregate view (totals per client
+or per month) is an `object.report` (`references/declaring-reports.md`); `@sql` is for what neither
+can express (a recursive CTE, a window function, a set operation).

agent-context/templates/always-on.md.mustache

@@ -50,6 +50,9 @@ Commit the metadata, the generated code, `.metaobjects/migrations/` and
 - Once the project declares a `template.prompt`, every LLM prompt is one: the text in a
   template, the data in a payload, a structured reply read through its generated extractor
   (`metaobjects-prompts`).
+- A grouped total, dashboard number or read-only report view (per client, per month) is an
+  `object.report` over `dimension.*` / `measure.*` (`metaobjects-authoring`,
+  `references/declaring-reports.md`). A hand-written `@sql` view body is the last resort.
 - Never invent metadata vocabulary. Search it: `npx meta types <term>`, and
   `npx meta types <type>.<subType> --detail` for one construct's valid attributes.
 - Metadata nodes are fused-key maps, `{"field.string": {"name": "email"}}`. Attribute names are

docs/CONFORMANCE.md

@@ -26,7 +26,7 @@ regenerate with `ls -d fixtures/<corpus>/*/ | wc -l` for directory-shaped corpor
 
 | Corpus | Fixtures | TS | Java | Kotlin | C# | Python |
 |---|---|---|---|---|---|---|
-| [`fixtures/conformance/`](../fixtures/conformance/) (metamodel) | 458 | ✓ | ✓ | inherits via `metadata-ktx` | ✓ | ✓ |
+| [`fixtures/conformance/`](../fixtures/conformance/) (metamodel) | 459 | ✓ | ✓ | inherits via `metadata-ktx` | ✓ | ✓ |
 | [`fixtures/yaml-conformance/`](../fixtures/yaml-conformance/) | 16 | 16 / 16 | 15 / 16 (1 ledgered: `yaml-quoted-leading-zero` — Java pipeline strips quotes off `"007"`) | inherits via Java | 15 / 16 (1 ledgered: `error-yaml-coerced-hex-in-string` — YamlDotNet doesn't coerce `0xFF`) | 16 / 16 |
 | [`fixtures/verify-conformance/`](../fixtures/verify-conformance/) | 45 | ✓ | ✓ | inherits via Java | ✓ | ✓ |
 | [`fixtures/verify-strict-conformance/`](../fixtures/verify-strict-conformance/) | 1 | ✓ | — | — | — | ✓ |
@@ -354,7 +354,7 @@ unit-test runners (`bun test`, `dotnet test`, `pytest`, `mvn test`) pull Docker.
 
 ## Fixture-to-doc mapping
 
-### `fixtures/conformance/` — metamodel loader + canonical serializer (458)
+### `fixtures/conformance/` — metamodel loader + canonical serializer (459)
 
 | Fixture prefix | Feature doc |
 |---|---|
@@ -716,7 +716,7 @@ JSON and verify payload feeds it unchanged.
 
 ## Orphaned fixtures (tested but not yet documented)
 
-The fixtures in the nine corpora mapped above (metamodel 458 + yaml 16 + verify 45
+The fixtures in the nine corpora mapped above (metamodel 459 + yaml 16 + verify 45
 + render 18 + persistence 62 + api-contract 123 + source-resolution 25 + scope 10 +
 dependency 47) each map to a feature doc, and so do the two requirement corpora, `shared-model-conformance`, the
 `cube-model` corpus and `explorer-conformance`, whose case lists live in their own READMEs. None are orphaned today. The remaining

docs/features/source-kinds.md

@@ -182,6 +182,12 @@ max over only the active rows — the filtered-scalar shape a plain aggregate ca
 ]}}
 ```
 
+**`sum` / `avg` / `min` / `max` need a scalar `@of`.** A value-object field (`field.object`,
+flattened or jsonb) is several columns or a document, so there is no one column to reduce, and a
+Money-shaped sum would add amounts in different currencies. The loader refuses it in every port
+(`ERR_INVALID_ORIGIN`); model the amount as its own scalar field and group by its currency.
+`count` still counts rows.
+
 **More `origin.aggregate` reductions (#195).** Beyond the scalar reduces, `@agg` also takes
 `any` / `all` (predicate quantifiers over a `@filter` — `@of` forbidden; empty set →
 `any=false`, `all=true`) and `collect` (an array rollup of `@of` into an `isArray` field,

examples/showcase/site-payload.json

@@ -7,7 +7,7 @@
     "metamodel": "1.3"
   },
   "counts": {
-    "fixtures": 458,
+    "fixtures": 459,
     "corpora": 38,
     "baseTypes": 17
   },

fixtures/agent-context-conformance/csharp/expected/.claude/skills/metaobjects-authoring/SKILL.md

@@ -31,10 +31,10 @@ This file covers what almost every model needs. The topics below live in
 | `references/identities-and-indexes.md` | declaring a primary, secondary or reference identity, an FK, or a non-unique `index.lookup` |
 | `references/sources.md` | the `source.rdb` shape and `@kind`; a store MetaObjects does not manage; a derived or computed column (reach for an entity read-view first) |
 | `references/abstracts-and-overlay.md` | a shared `abstract` base, `extends`, or a layered `overlay` file |
-| `references/declaring-reports.md` | declaring `dimension.*`, `measure.*`, `segment.filter` or an `object.report` |
+| `references/declaring-reports.md` | **open first** for a report, dashboard, totals, `GROUP BY`, "per client / per month" or a read-only summary view: declaring `dimension.*`, `measure.*`, `segment.filter` or an `object.report` |
 | `references/model-first-rationale.md` | someone argues that hand-writing a layer is cheaper this once |
 | `references/relationships.md` | a many-to-many link or self-join, or a "rows that reference this one" query |
-| `references/read-views-and-projections.md` | an `object.projection`, `origin.*` vocabulary, `@filter` / `@expr`, or an `@sql` / `@unmanaged` view |
+| `references/read-views-and-projections.md` | an `object.projection`, `origin.*` vocabulary, `@filter` / `@expr`, or an `@sql` / `@unmanaged` view (a grouped or aggregate view is `declaring-reports.md` first) |
 | `references/inheritance-tph.md` | several entities are variants of one thing sharing a single table (`@discriminator`) |
 | `references/metadata-dependencies.md` | the project builds on another package's metadata (`dependencies`, cross-package `overlay`) |
 | `references/reporting.md` | what a declared report gives you: what columns a report gets, time grains, null rules, rows with no facts (`@spine`), defaults (`@default`), engine differences |

fixtures/agent-context-conformance/csharp/expected/.claude/skills/metaobjects-authoring/references/read-views-and-projections.md

@@ -1,6 +1,6 @@
 # Projections, `origin.*`, and managed views
 
-> Part of the `metaobjects-authoring` skill. The skill covers the entity read-view, which is the right answer for most grids. Read this when you need an independent exposure (`object.projection`), the `origin.*` vocabulary, `@filter` / `@expr` shapes, or an `@sql` / `@unmanaged` view.
+> Part of the `metaobjects-authoring` skill. The skill covers the entity read-view, which is the right answer for most grids. Read this when you need an independent exposure (`object.projection`), the `origin.*` vocabulary, `@filter` / `@expr` shapes, or an `@sql` / `@unmanaged` view. A grouped total or report (per client, per month) is an `object.report`: `declaring-reports.md`.
 
 ## Contents
 - Read-view or projection?
@@ -125,8 +125,9 @@ non-aggregate-derived** projection fields: naming an undeclared field fails the
 
 **The `CREATE VIEW` body is generated from those `origin.*` children by the Node
 `meta migrate` — never hand-author view SQL for a shape origins can express** (an unmodeled
-view is *unmanaged*, so `meta verify --db` can't even catch the drift). For a genuinely
-irreducible body (recursive CTE, window function, set operation) that origins can't express,
+view is *unmanaged*, so `meta verify --db` can't even catch the drift). **An `@sql` body that
+`GROUP BY`s: check `declaring-reports.md` first** (`object.report`, `@spine`, `@default`).
+For a genuinely irreducible body (recursive CTE, window function, set operation) that origins can't express,
 carry it in the `source.rdb` **`@sql`** escape (#208, ADR-0043) — a hand-written body the
 tool registers, fingerprints, and drift-checks (adopt a pre-existing view with
 `meta migrate --allow adopt-view`) — rather than a hand-edited migration file where it goes

fixtures/agent-context-conformance/csharp/expected/.claude/skills/metaobjects-authoring/references/sources.md

@@ -94,4 +94,6 @@ column because the filter tier runs against the view.
 **When you need an independent exposure** — a subset, renamed columns, a row-filtered
 view, a versioned or external shape — that is an `object.projection`. It, the `origin.*`
 vocabulary, the structured `@filter` / `@expr` shapes and the `@sql` / `@unmanaged` escapes
-are in `references/read-views-and-projections.md`.
+are in `references/read-views-and-projections.md`. A grouped or aggregate view (totals per client
+or per month) is an `object.report` (`references/declaring-reports.md`); `@sql` is for what neither
+can express (a recursive CTE, a window function, a set operation).

fixtures/agent-context-conformance/csharp/expected/.metaobjects/AGENTS.md

@@ -68,6 +68,9 @@ Commit the metadata, the generated code, `.metaobjects/migrations/` and
 - Once the project declares a `template.prompt`, every LLM prompt is one: the text in a
   template, the data in a payload, a structured reply read through its generated extractor
   (`metaobjects-prompts`).
+- A grouped total, dashboard number or read-only report view (per client, per month) is an
+  `object.report` over `dimension.*` / `measure.*` (`metaobjects-authoring`,
+  `references/declaring-reports.md`). A hand-written `@sql` view body is the last resort.
 - Never invent metadata vocabulary. Search it: `npx meta types <term>`, and
   `npx meta types <type>.<subType> --detail` for one construct's valid attributes.
 - Metadata nodes are fused-key maps, `{"field.string": {"name": "email"}}`. Attribute names are

fixtures/agent-context-conformance/csharp/expected/.metaobjects/CLAUDE.md

@@ -68,6 +68,9 @@ Commit the metadata, the generated code, `.metaobjects/migrations/` and
 - Once the project declares a `template.prompt`, every LLM prompt is one: the text in a
   template, the data in a payload, a structured reply read through its generated extractor
   (`metaobjects-prompts`).
+- A grouped total, dashboard number or read-only report view (per client, per month) is an
+  `object.report` over `dimension.*` / `measure.*` (`metaobjects-authoring`,
+  `references/declaring-reports.md`). A hand-written `@sql` view body is the last resort.
 - Never invent metadata vocabulary. Search it: `npx meta types <term>`, and
   `npx meta types <type>.<subType> --detail` for one construct's valid attributes.
 - Metadata nodes are fused-key maps, `{"field.string": {"name": "email"}}`. Attribute names are