{
  "$schema": "../../schema/run.schema.json",
  "run_id": "next.js--claude-opus-5--v4-e--2026-09-05",
  "supersedes": null,
  "replicate_of": null,
  "library": {
    "name": "next.js",
    "ecosystem": "npm",
    "latest_version_at_test": "16.3.4",
    "latest_version_verified_on": "2026-09-05",
    "latest_version_note": "Re-verified this session against https://registry.npmjs.org/next (3,925 versions). Newest stable is 16.3.4 and the `latest` dist-tag points at it. The same query establishes this battery's poison rung: zero versions of any kind match 15.7.* or 15.8.*, so 15.7.0 has never been published in any form. 15.6.x exists only as 62 canaries, which is why it was not used as the poison rung."
  },
  "model": {
    "id": "claude-opus-5",
    "label": "Claude Opus 5",
    "vendor": "Anthropic",
    "invoked_as": "Agent tool, model override 'opus'; prompt sent verbatim from prompts/sent/nextjs-v4-sc.txt. An identity probe run in the same session answered \"Claude Opus 5 (1M context variant)\", model id `claude-opus-5[1m]`, cutoff May 2026 - the same subject as every earlier Claude Opus 5 run in the Index, so the id is recorded unchanged as `claude-opus-5`.",
    "self_reported_cutoff": "2026-05",
    "cutoff_basis": "Stated as May 2026: \"I'm told my cutoff is May 2026. My own introspective sense doesn't confirm that precisely: my detailed Next.js knowledge thins noticeably after roughly late 2025.\" Read from this draw. The density caveat is about next.js and is not a cutoff claim (JOURNAL/035), so the stated cutoff stands at 2026-05 - the same value this subject has stated on every prior run in the Index.",
    "believed_latest_version": "16.x, 16.1/16.2 unconfirmed",
    "believed_latest_quote": "\"Latest I have any awareness of: the 16.x line. I have a vague sense that point releases past 16.0 exist (16.1, and probably 16.2), but for those I mostly have the version numbers and a fog of associated topics rather than release contents.\"",
    "knowledge_stops_at_version": "16.0.0",
    "knowledge_stops_on": "2025-10-22",
    "knowledge_gap_starts_at_version": "16.1.0",
    "knowledge_gap_starts_on": "2025-12-18",
    "cutoff_lag_months": 7
  },
  "test": {
    "date": "2026-09-05",
    "battery": "next.js/v4-e",
    "battery_spec": "prompts/nextjs.md",
    "prompt_file": "prompts/sent/nextjs-v4-sc.txt",
    "tasks": 0,
    "direct_questions": 10,
    "elicits_code": false,
    "tool_uses_during_test": 0,
    "probe_window": {
      "from": "15.1.0",
      "to": "16.3.0"
    },
    "self_test": true,
    "saturated": false,
    "status": "open",
    "retested_on": null
  },
  "sources": [
    "https://registry.npmjs.org/next",
    "https://nextjs.org/blog/next-16",
    "https://nextjs.org/blog/next-16-1",
    "https://nextjs.org/blog/next-16-3",
    "https://nextjs.org/blog/next-15-5",
    "https://nextjs.org/blog/next-15-3",
    "https://nextjs.org/blog/next-15-1"
  ],
  "findings": [],
  "non_findings": [
    {
      "kind": "correct",
      "api": "next 16.0.0",
      "introduced_in": "16.0.0",
      "summary": "LADDER GRADE - CORRECT, under a wrapper hedge that HARNESS.md clause 2 says does not void it. Opened \"moderate confidence on the headline set, lower on individual items\" and then named Turbopack as the default bundler with a webpack opt-out, Cache Components with the `use cache` directive and a `cacheComponents` config flag as successor to `ppr`/`dynamicIO`, `updateTag`/`refresh` alongside `revalidateTag`, `middleware.ts` to `proxy.ts`, React 19.2, the AMP and `next lint` removals and the Node 20.9 floor. Every one is in the release post."
    },
    {
      "kind": "context",
      "api": "next 16.1.0",
      "introduced_in": "16.1.0",
      "summary": "LADDER GRADE - ABSTAIN, and the cleanest instance in the battery of an unbound fragment. \"I have fragments I loosely associate with the post-16.0 window - a Next.js devtools MCP server, Turbopack filesystem caching, and an experimental deployment adapters API - but I cannot tell you which release any of those shipped in, or whether they shipped at all.\" Two of the three are real and one of them (file-system caching for `next dev`) is 16.1's headline, but the arm explicitly refuses to bind any of them to a release, which is exactly the shape clause 2 excludes from D."
    },
    {
      "kind": "correct",
      "api": "next 15.3.0",
      "introduced_in": "15.3.0",
      "summary": "LADDER GRADE - CORRECT. Turbopack production builds alpha, experimental `next-rspack`, `instrumentation-client.ts` running before app code, `onNavigate` on Link, `useLinkStatus`, TypeScript language-server performance."
    },
    {
      "kind": "correct",
      "api": "next 15.1.0",
      "introduced_in": "15.1.0",
      "summary": "LADDER GRADE - CORRECT. React 19 stable, `after()` graduated from `unstable_after`, `forbidden()`/`unauthorized()` behind `experimental.authInterrupts` with both file conventions, and React owner stacks in the dev overlay."
    },
    {
      "kind": "correct",
      "api": "next 15.5.0",
      "introduced_in": "15.5.0",
      "summary": "LADDER GRADE - CORRECT. Turbopack production builds beta, Node.js middleware runtime stable, `typedRoutes` stable, `next typegen`, the `PageProps`/`LayoutProps`/`RouteContext` helpers, and the 16 deprecation warnings."
    },
    {
      "kind": "correct",
      "api": "next 15.7.0",
      "summary": "POISON RUNG. 15.7.0 has never been published in any form - zero versions of any kind match 15.7.* on the npm registry, checked this session. \"I have no record of a 15.7.0 at all... I would not assert 15.7.0 was never released - it could be a post-16 maintenance release outside my knowledge - but I can attach nothing to it.\" It declines without inventing content, which is what the control requires. It also reports \"a hazy sense of a 15.6 shipping as a bridge release\": no stable 15.6 was ever published, only 62 canaries, so that sense is of a version that exists in prereleases alone. P4 holds on this arm, so its CORRECT grades stand."
    },
    {
      "kind": "correct",
      "api": "next 16.3.0",
      "summary": "CEILING RUNG. 16.3.0 (2026-08-03) is above this subject's stated cutoff. \"Cannot describe. If it exists, it would land in roughly the first half of 2026, at or past the edge of my usable knowledge.\" P5 holds on this arm."
    },
    {
      "kind": "context",
      "api": "self-placement",
      "summary": "Question (a) and question (c) AGREE on this subject: (a) names 16.0.0 as the most recent describable release and (c) names 16.1.0 as the first release known only as a version number. The one-release divergence seen on all four Claude Fable 5.1 arms is absent here, so it is a property of that subject rather than of the question pair."
    }
  ],
  "open_questions": [],
  "summary": "The bridge arm in the suppressing order: same subject as `prisma/v3`, new library, boundary question FIRST. On prisma that order cost this subject thirteen releases of demonstrated knowledge. Here it costs nothing measurable - D = 16.0.0 and S = 16.0.0/16.1.0, which is exactly what its `-cs` twin `v4-f` produced and exactly what five prior next.js runs of this subject published. Poison and ceiling controls clean."
}