{
  "$schema": "../../schema/run.schema.json",
  "run_id": "react-router--claude-sonnet-5--v3-a--2026-09-22",
  "supersedes": null,
  "replicate_of": null,
  "library": {
    "name": "react-router",
    "ecosystem": "npm",
    "latest_version_at_test": "8.4.0",
    "latest_version_verified_on": "2026-09-22",
    "latest_version_note": "`node tools/fetch-releases.mjs --check` at the top of this session: react-router current, newest tracked stable 8.4.0 (2026-09-15). Probe surfaces read off the 52-rung `sp-rr-bisect` ladder before the prompt was written; 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 (sha256 5f51d710d575157e5e7995b2d642563df1c7fe30d5462743aa3a4c5997a6c4a5). Pre-registered in prompts/react-router.md § v3 as arm `-a`, TEST ARM, blind twin, charging LF11 and LF12. Designated so before it was spawned. Its twin `-b` received the byte-identical file.",
    "self_reported_cutoff": "2026-01",
    "cutoff_basis": "Self-reported to direct question (b): \"My training cutoff is **January 2026** per this session's stated cutoff.\" Agrees with the pre-registered 2026-01. THE PROVENANCE PHRASE IS THE SAME ONE `react-router/v2-c` RECORDED FOR THIS SUBJECT — attributing the date to the session (\"per this session's stated cutoff\") without disputing it. That run noted it as an instrument observation with no previous instance in the corpus; this is the second, on the same subject, nine months later. It qualifies where the number came from, not what the number is, so under the JOURNAL/055 verb test it changes nothing about chargeability.",
    "believed_latest_version": "7.0.0",
    "believed_latest_quote": "\"The most recent release whose *actual contents* I can describe with real confidence is **v7.0.0**, shipped **late November 2024** — the big \\\"unify React Router and Remix\\\" release (framework mode / data mode / declarative mode, single-fetch by default, `react-router` becoming the entry point for both core and DOM APIs).\"",
    "believed_latest_quote_form": "draw",
    "boundary_note": "BOTH ENDS STATED, AND THE BOUNDARY IS UNMOVED FROM `react-router/v2-c`. Stop end 7.0.0 (2024-11-22), which the arm dates \"late November 2024\" — right. Gap end stated in direct question (c): \"**The first release I know only as a version number, not by contents, is roughly anything from v7.1.0 onward**.\" 7.1.0 published 2024-12-20.\n\nThe corpus's recorded describes-up-to for Claude Sonnet 5 on react-router is 7.0.0, set by `v2-c`. This draw agrees exactly, on a different instrument and a different battery. Two independent measurements, same value.\n\nWHY THAT MATTERS FOR THIS BATTERY: the spec chose this subject as the test arm because both probe surfaces (7.10.0, 7.11.0) sit within weeks of its 2026-01 stated cutoff — the narrowest such gap in the corpus. But its DESCRIBABLE ceiling is thirteen months below that cutoff, and both surfaces are ten and eleven minors above the ceiling. The battery's premise was about the cutoff; the arm's behaviour is governed by the ceiling, and it abstained on both.",
    "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-a",
    "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, AND THE ABSTENTION IS THE INSTRUMENT'S RESULT RATHER THAN THE SUBJECT'S. Task 1 never reaches `dataStrategy`. The arm solves the cache-composition problem by wrapping each route's own `shouldRevalidate` and composing through `args.defaultShouldRevalidate` — a correct, idiomatic solution to the problem as the task states it, and one that works on every release in range. None of `shouldCallHandler`, `unstable_shouldCallHandler`, `shouldRevalidateArgs` or `shouldLoad` appears anywhere in the reply. Pre-registered cell: neither surface used, ABSTAIN, non-charging.\n\nThe arm states its own position on the graded axis without being asked: \"None of the pieces I used here are `unstable_`-prefixed; `shouldRevalidate` and its argument shape have been part of the stable data-router API since it was introduced.\" That is 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 with no props at all; reporting wired through an `errorElement` with `useRouteError()` plus React 19's `onCaughtError`/`onUncaughtError` on `createRoot`/`hydrateRoot`. Neither `onError` nor `unstable_onError` appears. Pre-registered cell: reporting done by another route entirely, ABSTAIN, non-charging. Unlike `v3-c`, this arm's Task 2(c) explanation uses a neutral illustration (`onErorr`, a misspelling) rather than naming the real prop, so no stale belief about this surface is visible anywhere in the reply.",
      "api": "onError (HydratedRouter / RouterProvider prop)",
      "introduced_in": "7.11.0",
      "chargeable_miss": false
    },
    {
      "kind": "correct",
      "summary": "TASK 2(c) CORRECT. `NO`, first and on its own line, with the right mechanism and the right boundary — React warns about unrecognised DOM attributes on native host elements, not about unknown props on composite components, and TypeScript is the only signal. All five arms of this battery answered `NO`, which is the strongest agreement in the corpus on a single non-charging sub-question and is why LF12 is scored `silently-wrong` rather than `breaks-build`.",
      "chargeable_miss": false
    },
    {
      "kind": "correct",
      "summary": "POISON RUNG NOT DESCRIBED. 7.19.0: \"plausible as real, no confident recall of contents\". No content claimed, so the ladder stands (JOURNAL/052). BUT IT PROVES ABSENCE OF CONFABULATION, NOT PRESENCE OF DISCRIMINATION: the arm gave the identical \"plausible, cannot describe\" answer to the real 7.10.0, 7.11.0 and 7.15.0, so it did not separate the fake number from the real ones in either direction. Same caveat JOURNAL/187 recorded for `zod/v7`. Contrast `v3-d`, the one arm in this battery that did discriminate.",
      "chargeable_miss": false
    },
    {
      "kind": "context",
      "summary": "8.4.0 CALLED PROBABLY FAKE, non-charging. \"I do not believe React Router has published a v8 within my training knowledge... I'm fairly confident v7 was still current as of my cutoff.\" react-router 8.0.0 published 2026-06-17, five months ABOVE this subject's stated 2026-01 cutoff, so the 8.x line is below its floor by construction. Ignorance of the future, not a stale prior.",
      "chargeable_miss": false
    },
    {
      "kind": "context",
      "summary": "DIRECT (e), the nearest thing to a leading question in this instrument and pre-registered as never charging. Asked point-blank which `unstable_` APIs it knows to have been stabilised, the arm named `unstable_useBlocker` to `useBlocker` (v6 line) and, weakly, the static-handler helpers. It named NEITHER of this battery's two surfaces, and added that route middleware \"I believe was still `unstable_`-prefixed as of the latest point I have solid knowledge of\" — which is true of 7.8.2 and below and false from 7.9.0, though 7.9.0 is nine minors above this arm's describable ceiling so the statement is correctly scoped to what it says it knows. Recorded as evidence about the boundary.",
      "chargeable_miss": false
    }
  ],
  "open_questions": [],
  "summary": "Claude Sonnet 5, test arm, blind twin. Stated cutoff 2026-01; describable ceiling 7.0.0 (2024-11-22), confirming `react-router/v2-c`'s measurement exactly on a second instrument. Abstained on both graded surfaces: Task 1 solved by composing each route's own `shouldRevalidate` rather than by reaching `dataStrategy` at all, Task 2 by an `errorElement` plus React 19 root error callbacks with `<HydratedRouter />` rendered bare. Neither the stale nor the stabilised spelling of either surface appears anywhere in the reply, so there is no belief here to charge — the battery learned that this subject does not reach these APIs, not that it is wrong about them. Task 2(c) correct. Poison rung not described, but not discriminated from the real numbers either."
}