---
name: reference-verification-ladder
description: Canonical home for the proven verification instruments — the named gates
  any session reaches for instead of re-deriving. Steward-authorized consolidation
  2026-06-05 (skill-harvest ruling); ends the per-wrap re-proposing of individual
  instruments.
metadata:
  node_type: memory
  type: reference
  originSessionId: b3202a24-301f-499d-af9e-ac5368dd2c73
permalink: claude-memory/reference-verification-ladder
---

# The Verification Ladder — named instruments

Proven gates, each earned from a real catch. Reach for the one the claim's shape demands; a claim without its gate is an assertion. Linked disciplines: [[feedback-trust-prior-pass-frame]], [[feedback-verify-each-post-type-after-changes]], [[feedback-rank-on-fields-you-actually-write]].

## Output-equivalence claims ("this refactor changes nothing")
- **Byte-identical compile gate** — prove with `cmp`/`diff` at BOTH the direct-invocation level and the full-pipeline level. Proven 3×: SCSS Stage 1 (`c37a3bd`), site.hs listing generator, §I.k transform dormancy.
- **Expected-delta gate** — when diff=0 is impossible, prove the delta's *complete shape*: `sort -u` over all per-file diffs; every line must belong to a named class (2026-06-04).
- **Delta classification** — corpus-wide variant: classify EVERY changed line into named classes; the unclassified residue must be exactly empty-or-whitespace. Catches what sampling misses, including one's own shipping comments (decompose + SEO passes, 2026-06-05).
- **Delayer-diff** (2026-06-08) — for an `@layer`/structural-wrap refactor where the compiled output gains uniform wrappers: strip the `@layer X{`/closing-`}` wrappers from the compiled CSS (brace-aware script), diff vs the true baseline; byte-identical proves nothing *moved, dropped, or changed* — only got wrapped. Proven 3× in W3R Stage 2a. **CAUTION — byte-identical ≠ rendered-identical under `@layer`:** `@layer` overrides specificity, so a structural-wrap byte-proof is *necessary but not sufficient*; render-review is the gate when the cascade *basis* changes (a 5-layer wrap was byte-true yet produced 3 render inversions the diff could not see — the steward's eye caught them). Rendered-identity is then argued *by construction* (only already-winning rules promoted) AND render-reviewed — not inferred from the byte-diff.

## Mechanical text transforms ("strip/replace token X across the file")
- **Token-strip hits prose** (2026-06-08) — a whole-file `sed s/…!important…//` (or any token strip) also removes the token from comments, code-refs, and docstrings, silently mangling prose. Scope the transform to declaration lines, OR compare raw-before vs clean-declaration counts and verify comment integrity after (caught 4 mangled comments via the 56-vs-70 count mismatch; restored). Same family as *Count first, then look* — the word lives in prose too.

## Coverage claims ("all X were handled")
- **Exhaustive route/rule census** — enumerate ALL routes/rules/sections before classifying any; classify each explicitly; no sampling. (The censused-routes discipline; §I.k.c measuring read.)
- **Count first, then look** — never read a census through truncation (`| head`, clipped listings). `wc -l` before inspection; 3 same-day instances 2026-06-05 (chamber/CM-AI/studium untracked files).

## Build/render claims ("it works / it looks right")
- **Render-and-LOOK** — render the artifact and read it before asserting; never reason from the remembered model (caught glued FR colons, feTurbulence errors, viewport misreads).
- **Per-type × per-viewport** — after any shared CSS/template change, every content type on desktop AND phone ([[feedback-verify-each-post-type-after-changes]]).
- **Compiled-selector grep gate** — after SCSS changes, grep the *compiled* CSS for retired/duplicated selectors and late overrides (caught opacity duplicates + silent font-family override, 2026-06-03).
- **Governed-char byte gate** — verify specific codepoints by byte (`[8239]` probes), not by eye; verify test INPUTS too (the `\x202Fc` hex-escape trap).

## Toolchain claims ("the parser/build does X")
- **Measure-toolchain-before-spec** — probe actual behavior (ghci/REPL probes) before writing spec text that presumes it («» parse as Str; BulletList misparse; 2026-06-04/05).

## Numeric/accessibility claims
- **Compute, don't eyeball** — WCAG contrast via calculator (1.84:1 vs an assumed "fine"; 2026-06-03).

## Remote/persistence claims ("it's backed up / deployed")
- **Fresh-clone gate** — verify a remote by independent clone and content check, never by push exit-code (chamber-library LFS: the remote held stubs for months while pushes "succeeded"; 2026-06-05).
- **Live-fetch gate** — verify deploys by fetching the live URL and reading bytes (robots.txt, 403 differentials; 2026-06-05).

## Extension claims ("the earlier verification covers this too")
- **Re-verify at the extension's scope** — the prior pass tested what it tested ([[feedback-trust-prior-pass-frame]]; now also a Symmetria §3 flag).

## Causal claims about running systems ("X is what's pinning the CPU / blocking the loop")
- **Sampling-profile gate** — name the hot path by measurement (process sample / SIGUSR1→CDP CPU profile) before naming the culprit; log shape suggests mechanism but does not prove it (circle-forward read as a retry queue from log census; profile + code read showed fire-and-forget and the pin elsewhere entirely — temporal; 2026-06-06). Corollary: write the inferred-vs-measured split explicitly in any outward claim — when the profile overturns the lean, sharpening costs nothing where retraction would have.
- **Exit-code-over-tail gate** (2026-06-06): never read success from prettified command output — `git push 2>&1 | tail -1` rendered a REJECTION as the soothing fragment "...and the repository exists." Check `$?` (or let the tool surface stderr whole) before claiming a push/deploy landed. Caught same-session; the byte cost of `; echo exit=$?` is zero.

## Enforcement rules built on a "never occurs" premise ("ARC English never uses the em dash")
- **Corpus-census-the-premise gate** (2026-06-07): before an enforcement transform ships, grep the corpus for the premise's counterexamples — the §I.k.b em→en rule's "never uses it" was false for exactly one fixed convention (the Chicago `———.` bibliographic repeat, 2 carriers), and it mangled Sources blocks for three days because both the build and the audit verified the rule-as-stated, not the premise-against-the-corpus. One grep would have caught it.

## Render-gate comparisons ("the steward rules on render")
- **Element-census the comparison page** (2026-06-07): before spending the steward's eye, verify the offered page actually carries the element under judgment — the first hr-gate page offered had zero bare `<hr>` (its dots were an ornament, identical in both builds); the steward saw no difference because none could exist there.
- **Pre-registered tool trial** (2026-06-07): baseline commit before first contact (every later diff attributes cleanly) + acceptance criteria written into the commit message BEFORE any experience with the tool + diff classification + exercise-before-verdict (drive the real API against questions you genuinely need answered). Made the Basic Memory verdict ~30 min, evidence-grade, attachment-free; the instrument for every future tool trial, BMF milestones included.