- Route every Makefile python target through uv run --python 3.13 so
  make verify works regardless of system python; fix make dev/deploy to
  use the workers dependency group.
- Wire audit_example_graph and three forthcoming content gates into
  quality-checks.
- Git hooks now regenerate embedded example data as well as the asset
  manifest; merge=ours covers src/example_sources_data.py too.
- verify.yml: drop duplicate PR runs, add permissions and concurrency.
- preview.yml: pass workflow inputs via env (no shell interpolation next
  to the Cloudflare token), pin wrangler, pass PBE_SMOKE_BYPASS_SECRET.
- regenerate-generated-files.yml: pull before building and retry with
  rebuild on push races, so stale generated output cannot land on main.

https://claude.ai/code/session_018EpcfENTg7herPR712vZeE

New tools:
- scripts/_common.py shares the root/loader/registry plumbing.
- check_program_covers_cells: an executable cell wholly disjoint from
  the :::program block fails; standalone_cells frontmatter opts out
  visibly.
- check_prose_duplication: verbatim repeated paragraphs, cell prose
  copying the intro, and duplicate note bullets fail.
- check_inline_links: prose links must be real /examples or /journeys
  targets; render_inline (now in src/textfmt.py) renders them as
  anchors, shared with figure captions so backticks render as code.

Gate integrity:
- score_example_criteria fails when a curated score exceeds the
  heuristic by more than --max-delta (default 1.5).
- check_quality_scores: waiver expiry must be a future ISO date, stale
  waivers flagged, score ranges validated, journey_average_min enforced.
- check_confusable_pairs defends against substring shadowing and
  accepts regex patterns.
- check_registry_integrity enforces the paired_pages relationship via
  see_also; check_no_figure_rationales enforces review_after dates;
  check_notes_supported reads every :::note block.
- audit_rubric_snapshot computes its scoreboard, waiver lines, and
  findings from live registries and labels curated judgements instead
  of hardcoding PASS verdicts; --date defaults to today.
- lint_seo_cache covers editor.js; verify_examples reports slug/filename
  mismatches cleanly; audit_example_graph --check help is accurate.

Figures:
- New while-backedge figure so the while-loops banner actually draws
  the back-edge its caption describes; loop-shape caption rewritten to
  describe the three stopping rules.
- Canvas text is XML-escaped; new well-formedness and escaping
  contracts; anchor contract validates against rendered cells (the
  walkthrough list diverges on 10 examples); reverse section-figure
  containment; rendered-page figure-presence contract; mechanical
  caption contract (5c); args-kwargs dividers computed via mono_divider.
- The marginalia gestalt now renders one card per attachment with the
  production figcaption, so caption/figure disagreements are visible in
  review; prototypes regenerate in make build and check-generated
  covers public/prototyping plus untracked fingerprint copies.

https://claude.ai/code/session_018EpcfENTg7herPR712vZeE

Factual and code corrections:
- dicts: scope the RuntimeError claim to adding/removing keys (value
  reassignment is legal).
- type-hints: teach the PEP 695 type statement; keep TypeAlias as the
  labelled-deprecated legacy spelling.
- regular-expressions: stop promising compile-time speedups the re
  module's internal cache already provides.
- string-formatting: describe 05.1f as zero-padding to width five.
- constants: doc link points at typing.Final, matching the page.
- special-methods: __lt__ alone suffices for sorted(); warn that
  hashing mutable Bags makes them unfindable after mutation; fix the
  three /data-model/* links (plus async-await's /iteration/* one) to
  real /examples/* routes.
- operator-overloading: __add__/__eq__ return NotImplemented for
  foreign types as the note instructs, demonstrated with Vector == 5.

Demonstration gaps:
- async-await shows a plain sync def (the contrast the registry pair
  demands; caught by the hardened confusable-pairs gate).
- positional-only-parameters: clamp now visibly caps 12 to 10, and a
  new cell shows scale(value=4) raising TypeError; keyword-only gets
  the same enforcement demo.
- exceptions: broken/fixed parsers now diverge visibly on a buggy call.
- operators/numbers/decorators/casts-and-any: programs now contain the
  cell code they were missing (short-circuit demo, ratio use, __doc__,
  isinstance narrowing).

Honesty and structure:
- subprocesses/threads/networking unsupported-fragments say plainly
  that Run fails in the sandbox and outputs come from real CPython
  execution at build time.
- hello-world/truthiness/unpacking cells get cell-specific prose
  instead of copied intro paragraphs; sets drops a duplicate bullet.
- match-statements notes cover mapping extra-keys; bound-and-unbound
  notes name the Py2 history; generics/paramspec notes show PEP 695
  inline syntax; bytes-and-bytearray moves to the Text section;
  comprehensions prints the set through sorted().
- async-await figure anchor follows its cell to cell-1.

Golden fixture redesigned as an explicit structural snapshot:
refresh_golden_fixture.py regenerates it and prints a reviewable
structural summary (29 changed examples this refresh); the parity gate
now compares full cell structure including kinds through the loader
with no legacy walkthrough dependence.

Worker runtime and front-end hardening:
- worker_asgi_bridge: fix the onclose handler being assigned to onopen;
  encode/decode ASGI headers as latin-1 per spec; run one lifespan per
  app instead of startup/shutdown around every request.
- main.py: constant-time smoke-bypass comparison; unknown Turnstile
  modes fail closed to requiring a challenge; POST bodies over 100 kB
  rejected with a friendly 413 page; security headers (nosniff,
  referrer-policy, frame protections) on all Worker HTML; error
  responses on cacheable paths marked no-store.
- app.py: single-pass template substitution so user code containing
  __TOKEN__ text cannot corrupt the page; escape < in embedded JSON so
  </script> in example code cannot break out of the inline script;
  honest build_dynamic_worker_code docstring.
- example.html textarea gains an accessible label; site.css adds
  --accent-text (#C83800, 4.6:1) for small accent-colored text;
  screenshot script picks the Chrome path per platform.
- New behavioral test suite for clearance signing, challenge modes,
  cookie attributes, and cache keys (15 tests); execution test now
  asserts real expected output; quality-check tests cover the new gates
  plus negative cases proving each gate can fail.

https://claude.ai/code/session_018EpcfENTg7herPR712vZeE

- example-source-format-spec: implemented status header, checklists
  ticked as the historical record, :::unsupported and the
  expected_output/standalone_cells frontmatter documented, golden
  fixture policy rewritten for the structural-snapshot design, parity
  behavior matches the rewritten gate.
- example-figure-rubric: banner ceiling corrected to the rendered-width
  formula against 640px, grammar contracts relabelled to match the test
  suite (5/5b), new 5c caption contract and Contract 11 XML
  well-formedness documented.
- visual-explainer-spec and journey-visualisation-rubric: journey
  figures documented as the centered block between heading and list
  that production ships, not the 2-column layout that never did.
- example-quality-rubric: gate wording names the enforced 9.0 target /
  8.5 hard-minimum machinery; lessons-learned notes the fixture's
  post-migration role.
- turnstile spec: unknown challenge modes documented as fail-closed.
- example-graph doc: audit script moved from future work to its
  shipped, gated reality.
- README: features cover journeys, figures, Turnstile, and the quality
  gates; architecture lists the marginalia and textfmt modules; example
  workflow includes quality-checks and the fixture refresh.
- CONTRIBUTING: full 13-script gate table, an end-to-end new-example
  workflow, and a secrets/deploy-configuration section.
- CHANGELOG: Unreleased entry covering the toolchain, gates, runtime
  hardening, and content corrections.

https://claude.ai/code/session_018EpcfENTg7herPR712vZeE

Layers the non-overlapping parts of a parallel audit-remediation pass
onto the editorial-registry/security/CSP work already in HEAD. Only the
items the follow-up commit did not cover are included here; redundant
work (confusable code-scoping, broad-tour focused_neighbors, security
headers, the score-registry move) is intentionally omitted in favour of
the existing implementation.

Content correctness:
- special-methods: __lt__ now orders by contents (consistent with __eq__,
  which the old length-based __lt__ contradicted) and the __hash__ cell
  demonstrates the mutable-hash hazard it warns about — a Bag found in a
  set becomes unfindable after its items change.
- subprocesses / threads-and-processes / networking: drop the duplicated
  :::unsupported block that restated the executable cell's code; each page
  keeps one verified cell whose prose carries the mechanism plus one
  honest sentence about the sandbox boundary.

Figures:
- Remove dead grammar vocabulary (open_arrow, dispatch, register(between=),
  the orphaned ARROW_OPEN constant) — no callers.
- FigureSizeContract gains a banner-height check (<=440px displayed at
  banner width); new FigureLineTextCollisionContract (Contract 12) rejects
  a solid line striking a label. The latter caught a real collision in
  control-stop-boundary (the first-true arrow clipped the 'd' label),
  fixed by starting the arrow below the cell row.

Docs:
- rubric-saturation: 124 figures / 7 reused (was 109 / 12).
- observability-spec: cleanup snippet gains the not-used guard.
- rubric-audit-2026-05-12: marked superseded; journey count 24 -> 21.
- figure-rubric documents Contract 12 and the height check.

https://claude.ai/code/session_018EpcfENTg7herPR712vZeE

Test-only additions covering paths the follow-up commit left at the
source-substring level:

- RunExampleFlowTests drives the real run_example POST handler through
  the verification-required (asserts the data-turnstile-required
  attribute and that code does NOT run), missing-site-key, oversize-413,
  off-mode, and verify-then-set-clearance branches. The Dynamic Worker
  run and Turnstile siteverify call are stubbed so only handler control
  flow is exercised.
- DynamicWorkerCodeTests asserts build_dynamic_worker_code embeds code via
  repr (no closing-quote breakout) and defines the entrypoint.
- Bridge process_request: stub js/pyodide.ffi/workers and drive a trivial
  ASGI app through the non-streaming path (echoes body, status, latin-1
  headers), app-exception propagation, and the new max_body_bytes 413 cap
  (asserts the app never runs on an oversize body).

https://claude.ai/code/session_018EpcfENTg7herPR712vZeE