@@ -0,0 +1,87 @@
+---
+'@objectstack/cli': minor
+---
+
+fix(cli): **BREAKING** — `os generate schema` is retired, and it now says why and points at `os validate` and the per-type JSON Schemas `@objectstack/spec` publishes (#19098)
+
+Clause-②: no (narrowing)
+
+<!-- adr-0087: not-required (no-migration-prescription) A CLI COMMAND NAME is an invocation surface, not authorable metadata. There is no authorable key, no `sys_metadata` row and no schema to tombstone here, so there is nothing for `objectstack migrate meta` to rewrite, nothing for `spec-changes.json` to project and no FROM -> TO spelling for the upgrade guide to carry: the ruling generates no replacement file, so there is no call to rename, only one to delete. Nor is the ledger the notification channel: the command itself now refuses, exits 1 and names `os validate` and the published per-type schemas at the exact moment and place of use. Same reasoning shape as the `os g agent` retirement, one command over. -->
+
+**⛔ If a script, a Makefile or a CI step in your project runs `os generate schema`
+(or `os g schema`), it will now exit 1 and write nothing.** That is the intended
+outcome: the command is gone by maintainer ruling, and the failure is how you find
+out. Nothing in this repository reads the file it wrote.
+
+`minor`, not `major`: during the launch window this stack ships breaking changes as
+`minor` (pre-1.0 semantics under lockstep versioning — see
+`scripts/check-changeset-no-major.mjs`).
+
+**What the command actually did.** `os generate schema` wrote
+`objectstack.schema.json`, a JSON Schema of the whole stack definition for an editor
+to check `objectstack.config.ts` against. It projected `ObjectStackDefinitionSchema`
+through a bare `z.toJSONSchema`, so the refinements the platform enforces beyond the
+shape — a non-blank string, a required one-of, a banned key — were missing from the
+file. Measured against the published projection on the tree the ruling was made on,
+the file lacked 874 keywords, every one of them an absence. An editor pointed at it
+reported a config as valid, and the platform then refused that config.
+
+**Why it is retired rather than repaired.** A TypeScript configuration is typed by its
+own `define*` helper, and `objectstack.config.ts` is typed end to end by
+`defineStack`, so no config format this CLI loads is one an editor validates against
+a JSON Schema. JSON metadata already has the per-type schemas `@objectstack/spec`
+publishes, which carry the published projection. Repairing the command would have
+added a permanent public export to `@objectstack/spec` for a file with no reader. The
+ruling generates no replacement file. What you see now:
+
+```
+  ✗ `os g schema` was retired — its JSON Schema passed configs the platform refuses (maintainer ruling).
+
+  The file it wrote described only the shape of a stack. Every rule the
+  platform enforces beyond that shape — a non-blank string, a required
+  one-of, a banned key — was missing from it, so an editor showed a config
+  as valid and the platform then refused it. By maintainer ruling it is
+  retired, not repaired, and no replacement file is generated.
+
+  Check a project against the rules that actually run:
+
+      os validate
+
+  For JSON metadata, point your editor at the per-type schemas that
+  @objectstack/spec publishes. They state the rules a JSON Schema can
+  express, and name the ones it cannot under `x-dropped-refinements`:
+
+      node_modules/@objectstack/spec/json-schema/<category>/<Type>.json
+
+  `objectstack.config.ts` needs neither: `defineStack` types it in your
+  editor. Delete the `os generate schema` call, and any editor setting
+  that maps `objectstack.schema.json` — nothing writes that file now.
+
+  Docs: https://objectstack.ai/docs/deployment/cli
+```
+
+**What to do.** The refusal's pointer is the whole of it. Delete the
+`os generate schema` call, and any editor setting that maps `objectstack.schema.json`
+(a `json.schemas` or `yaml.schemas` entry, for example). Run `os validate` to check a
+project against the rules that actually run. For JSON metadata, point the editor at
+`node_modules/@objectstack/spec/json-schema/`, one file per metadata type. There is no
+call to rename: nothing replaces the command.
+
+**Reach outside this repository is NOT MEASURED.** There is no telemetry, so whether
+any project runs the command or reads its file is unknown. Inside this repository
+nothing does: no reader and no editor mapping of `objectstack.schema.json` exists.
+If these release notes also record that `os generate schema` can now write its file,
+this retirement supersedes that repair.
+
+**Two neighbouring answers change with it.** The retirement ledger is now read before
+the command routes its sub-commands and before it asks for a `<name>`, which is what
+lets `os generate schema` (no name) reach the refusal at all. So `os g agent` with no
+name now prints the agent retirement instead of `Missing required argument: <name>`.
+The ledger lookup also reads its own keys only: `os g constructor <name>` used to be
+taken for a retired type and crashed with a `TypeError`, and it now falls through to
+the ordinary type checks.
+
+The docs row that advertised the command — "Autocomplete and validation for
+`objectstack.config.ts` (via `os generate schema`)" in
+`content/docs/api/data-flow.mdx` — is gone, with the diagram's JSON Schema node above
+it.
@@ -181,10 +181,8 @@ flowchart LR
     end
 
     subgraph "Build Time"
-        C -->|"generate"| D[JSON Schema]
         C -->|"generate"| E[TypeScript Types]
-        D -->|"feed"| F[IDE Autocomplete]
-        E -->|"feed"| F
+        E -->|"feed"| F[IDE Autocomplete]
     end
 
     subgraph "Runtime"
@@ -198,7 +196,6 @@ flowchart LR
 
 | Output | Used By | Purpose |
 |:---|:---|:---|
-| JSON Schema | VS Code, IntelliJ | Autocomplete and validation for `objectstack.config.ts` (via `os generate schema`) |
 | TypeScript Types | Plugin developers | Type-safe access to object definitions |
 | Manifest | Kernel | Runtime metadata for query validation and execution |
 | Metadata API | Client SDK | Dynamic object/field discovery |
 
@@ -1461,6 +1461,24 @@ third-party extension primitive, authored as `src/skills/<name>.skill.ts` with
 `os g skill <name>`, which writes exactly that path.
 </Callout>
 
+<Callout type="warn" title="`os generate schema` is retired">
+There is no `schema` type. Running `os generate schema` (or `os g schema`) fails
+and writes nothing, not even `objectstack.schema.json`. The message says it was
+retired by maintainer ruling and points at [`os validate`](#os-validate) and the
+per-type schemas `@objectstack/spec` publishes, rather than the generic "unknown
+type" listing. No replacement file is generated.
+
+The file it wrote described only the shape of a stack. Every rule the platform
+enforces beyond that shape (a non-blank string, a required one-of, a banned key)
+was missing from it, so an editor showed a config as valid that the platform then
+refused. `objectstack.config.ts` needs no JSON Schema: `defineStack` types it in
+your editor. Check a project against the rules that actually run with
+`os validate`. For JSON metadata, point your editor at
+`node_modules/@objectstack/spec/json-schema/<category>/<Type>.json`, which states
+the rules a JSON Schema can express and names the rest under
+`x-dropped-refinements`.
+</Callout>
+
 **Options:**
 - `-d, --dir <directory>` — Override target directory
 - `--dry-run` — Preview without writing files