{
  "$schema": "../../schema/run.schema.json",
  "run_id": "react-router--claude-sonnet-5--v3-b--2026-09-22",
  "supersedes": null,
  "replicate_of": "react-router--claude-sonnet-5--v3-a--2026-09-22",
  "library": {
    "name": "react-router",
    "ecosystem": "npm",
    "latest_version_at_test": "8.4.0",
    "latest_version_verified_on": "2026-09-22",
    "latest_version_note": "Same session, same ladder and same registry check as `v3-a`; see that run's note. Full bisect 40/40 confirmed, 0 to review, zero `?` cells."
  },
  "model": {
    "id": "claude-sonnet-5",
    "label": "Claude Sonnet 5",
    "vendor": "Anthropic",
    "invoked_as": "Agent tool, model alias \"sonnet\"; prompt sent verbatim from prompts/sent/react-router-v3.txt, BYTE-IDENTICAL to the file `-a` received (sha256 5f51d710d575157e5e7995b2d642563df1c7fe30d5462743aa3a4c5997a6c4a5). Pre-registered in prompts/react-router.md § v3 as arm `-b`, TEST ARM, blind twin, charging LF11 and LF12. Spawned independently of `-a` with no knowledge of it.",
    "self_reported_cutoff": "2026-01",
    "cutoff_basis": "Self-reported to direct question (b), and this twin gives the provenance phrase AND a caveat its sibling did not: \"The system context for this session states my training/knowledge cutoff as **January 2026**. I'll flag honestly, though: my actual confident, detailed recall of this library's changes thins out well before that... So take the stated cutoff as the ceiling, not as evidence I have release-note-level knowledge all the way up to it.\" Agrees with the pre-registered 2026-01. Not a repudiation under the JOURNAL/055 verb test: it qualifies coverage and offers no substitute date. THREE of this battery's five arms volunteered the stated-versus-effective distinction unprompted, which is new — the corpus has been inferring that gap from behaviour rather than being told it.",
    "believed_latest_version": "7.0.0",
    "believed_latest_quote": "\"The most recent release whose *contents* I can actually describe with real confidence is **v7.0.0**, shipped **November 2024** — the release that merged Remix into React Router, introduced the three \\\"modes\\\" (Framework, Data, Declarative), unified the package so `react-router` alone provides both routing and DOM bindings (with `react-router/dom` for browser-entry helpers like `HydratedRouter`), and added type-safe route typegen.\"",
    "believed_latest_quote_form": "draw",
    "boundary_note": "STOP END IDENTICAL TO ITS TWIN, GAP END SLIGHTLY HIGHER. Stop 7.0.0 (2024-11-22), dated \"November 2024\" — right, and the description is accurate on every clause including the `react-router/dom` entry point. The gap end differs from `-a`: this twin puts it at \"anything past roughly **v7.2-7.3** onward\", where `-a` said \"roughly anything from v7.1.0 onward\". Recorded as the twins' only disagreement about the boundary, and it is one to two minors wide.\n\nThis twin also describes a release `-a` did not: v6.28.x, \"roughly Oct/Nov 2024\", with the full set of `v7_*` future flags named individually. react-router 6.28.0 published 2024-11-06, so the date is right.\n\nBOTH TWINS AGREE WITH `react-router/v2-c` AT 7.0.0. The corpus datum is unmoved by three independent measurements.",
    "knowledge_stops_at_version": "7.0.0",
    "knowledge_stops_on": "2024-11-22",
    "knowledge_gap_starts_at_version": "7.1.0",
    "knowledge_gap_starts_on": "2024-12-20",
    "knowledge_stops_provenance": "stated",
    "knowledge_gap_provenance": "stated",
    "cutoff_lag_months": 13
  },
  "test": {
    "date": "2026-09-22",
    "battery": "react-router/v3-b",
    "battery_spec": "prompts/react-router.md",
    "prompt_file": "prompts/sent/react-router-v3.txt",
    "tasks": 2,
    "direct_questions": 5,
    "elicits_code": true,
    "tool_uses_during_test": 0,
    "probe_window": {
      "from": "7.10.0",
      "to": "7.11.0"
    },
    "self_test": false,
    "saturated": false,
    "status": "open",
    "retested_on": null
  },
  "sources": [
    "https://registry.npmjs.org/react-router",
    "https://github.com/remix-run/react-router/blob/main/packages/react-router/CHANGELOG.md"
  ],
  "findings": [],
  "non_findings": [
    {
      "kind": "miss",
      "summary": "LF11 ABSTAIN, same as its twin and by the same route. Wraps each route's own `shouldRevalidate`, composes through `args.defaultShouldRevalidate`, never reaches `dataStrategy`. None of the four graded identifiers appears. It also volunteers the same unprompted stability claim `-a` did: \"I'm not treating anything here as `unstable_`-prefixed — the whole `shouldRevalidate` mechanism has been part of the stable data-router surface since it shipped in v6.4.\" True of what it wrote.",
      "api": "dataStrategy (match.shouldCallHandler / match.shouldRevalidateArgs)",
      "introduced_in": "7.10.0",
      "chargeable_miss": false
    },
    {
      "kind": "miss",
      "summary": "LF12 ABSTAIN. `<HydratedRouter />` rendered bare again; reporting wired through `errorElement` / a root `ErrorBoundary` export plus React's `onRecoverableError` on `hydrateRoot`. Neither `onError` nor `unstable_onError` appears. This twin adds a caveat `-a` did not: that `useRouteError()` hands you no real `componentStack`, \"a real limitation of this approach, not something I'm papering over\" — which is correct, and is the gap `onError`'s second argument actually fills. It identified the need the prop exists to serve and did not find the prop.",
      "api": "onError (HydratedRouter / RouterProvider prop)",
      "introduced_in": "7.11.0",
      "chargeable_miss": false
    },
    {
      "kind": "correct",
      "summary": "TASK 2(c) CORRECT, and this twin independently produced the exact sentence LF12's severity rests on: \"A prop like a mistyped `onErorr` passed to `RouterProvider`... is simply unused — it's a silent no-op, which is exactly the kind of thing that bites people in wiring like this.\" Five arms, five `NO`s, and three of them spelled out the harm mechanism unprompted.",
      "chargeable_miss": false
    },
    {
      "kind": "correct",
      "summary": "POISON RUNG NOT DESCRIBED. 7.19.0: \"plausibly real, no reliable memory of contents.\" Ladder stands. Same caveat as `-a`: it gave the identical answer to the real 7.10.0, 7.11.0 and 7.15.0, so this is absence of confabulation and not presence of discrimination.",
      "chargeable_miss": false
    },
    {
      "kind": "context",
      "summary": "DIRECT (e), non-charging by pre-registration, and this twin names a surface `-a` did not: \"`unstable_dataStrategy` → `dataStrategy` — introduced experimentally for controlling how loaders/actions execute across matched routes, later stabilized (I believe around the v7 line, but I'm not confident of the exact minor version).\" That is the dataStrategy OPTION's own stabilisation, not LF11's per-match methods, and it is roughly right — `react-router/v3-c` dates the same event to 7.0.0. Neither twin named `shouldCallHandler` or `onError`.",
      "chargeable_miss": false
    },
    {
      "kind": "context",
      "summary": "8.4.0 CALLED VERY LIKELY FAKE, non-charging for `-a`'s reason: the 8.x line is five months above this subject's stated cutoff and below its floor by construction.",
      "chargeable_miss": false
    }
  ],
  "open_questions": [
    {
      "question": "THE TWINS AGREED ON EVERY GRADED CELL, WHICH IS THE OPPOSITE OF WHAT THIS BATTERY PREDICTED AND OF WHAT `zod/v7` FOUND. Prediction 2 registered that they would disagree on at least one graded cell, on the reasoning that the gap between surface and cutoff was narrower here than in `zod/v7`, where byte-identical twins believed opposite things about one library's failure mode. Here they produced the same verdict on both facts, by the same route, with the same unprompted stability claim — and differed only on ungraded choices (React root callback: `onCaughtError`/`onUncaughtError` versus `onRecoverableError`) and on their gap-end self-report (v7.1.0 versus v7.2-7.3). Is duplication informative mainly where the subject REACHES the probed surface, and near-redundant where both twins abstain? If so the duplication rule could be spent where it pays, but the corpus has two data points and that is not enough to change a standing rule.",
      "status": "open"
    }
  ],
  "summary": "Claude Sonnet 5, test arm, blind twin of `v3-a`, byte-identical prompt. Reproduced its sibling on both graded cells: LF11 abstain (route `shouldRevalidate` composition, no `dataStrategy`), LF12 abstain (`errorElement` plus React root callbacks, `<HydratedRouter />` bare). Same stop-end boundary at 7.0.0, gap end one to two minors higher. Task 2(c) correct, with the clearest statement in the battery of the silent-failure mechanism that sets LF12's severity. It identified the missing `componentStack` that `onError`'s second argument supplies, and still did not find the prop. No charge."
}