CB-WP-0017: legible interaction, and the chaos window's verdict

Provenance (tier M, structural S, chaos d4=4 -> OVERRIDE drawn M):
the maintainer could drag after CB-WP-0016 but could not tell what was
pickable, held, or droppable. Underneath that, the page was WRONG about
which moves exist: 9 legal commands rendered as 5 cards each claiming
all three target kinds, from a const string in the emitter. Investigate
is legal on problems 2 and 3 but not 1; Solve on 1 but not 2 or 3. The
live page now says 'Solve onto problem 1'.

ADR-0010 restates control 5, which this work would otherwise have
outgrown in silence: every game fact the page acts on must arrive from
Rust as data; the script may read, match and render it, never compute,
infer, filter or default one. The survey's real finding is that the
permitted and forbidden designs are indistinguishable from outside, so
the vocabulary grep is demoted to a cheap first line and two behavioural
properties become the controls -- the highlighted set EQUALS the set
Rust emitted, and anything the page marks legal must resolve. Both
mutation-proven; the derive-legality mutation produces a plausible
highlight (seat-0,1,2 where only seat-1 is legal) and is caught.

Visible now: .pick resting shadow, .held on the grabbed element, .dropok
on every legal target including BOTH drawings of a seat, and a ghost
following the pointer. Nothing perceptual is verified and ADR-0010 D5
says so.

The DOM stub now models classList/querySelectorAll/createElement and
builds its node set from the real emitted page. Trap recorded: QuickJS
fixes its stack limit at Context creation relative to that frame, so a
helper returning a Context makes every later eval report
'SyntaxError: stack overflow'.

CHAOS WINDOW CLOSED, 12 declarations, 2 overrides, one each way. Both
changed the outcome, so the retirement condition is not met. Verdict:
keep, and recommend d4 -> d8 with a second window of 12 -- that is a
change to the loop's own constraints and is owed to the next declaration
as tier-M work, not made here.

CB-EV-0014 corrected: it quoted CB-WP-0015 at $15.14/136 and called it
the first settled figure quoted. Now $22.70/166. The number had been
read during CB-WP-0015 itself, so there are two defects -- the boundary,
and quoting from memory instead of re-running the instrument.

make all exits 0.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

workplans/CB-WP-0017-legible-interaction.md

@@ -2,7 +2,7 @@
 id: CB-WP-0017
 kind: product
 title: "Legible interaction: what can be picked up, what is being dragged, where it can go"
-status: todo
+status: done
 ---
 
 # Purpose
@@ -66,7 +66,7 @@ It is the first time the page will tell the truth about what is legal.
 
 ```task
 id: CB-WP-0017-T01
-status: todo
+status: done
 priority: high
 ```
 
@@ -91,11 +91,23 @@ Decide, explicitly:
 - **The cost.** Marginal AM-4a is zero either way, so the budget does not
   decide this. Say what does.
 
+**Done 2026-08-02.**
+[ADR-0010](../decisions/ADR-0010-what-the-script-may-do.md) — *the script
+may render state it was given; it may not derive any.*
+
+The survey's real output: the permitted design (Rust emits legality, the
+script matches it) and the forbidden one (the script derives legality from
+the DOM) are **indistinguishable from the outside** — both are "the page
+highlights some elements". So the vocabulary grep is demoted to a cheap
+first line and the load-bearing controls are stated over behaviour: the
+highlighted set must **equal** the set Rust emitted, and anything the page
+marks legal must **resolve**. Both are mutation-proven below.
+
 ## Task: tell the truth about which moves are legal
 
 ```task
 id: CB-WP-0017-T02
-status: todo
+status: done
 priority: high
 ```
 
@@ -114,11 +126,20 @@ wrong.
   advertise a target `resolve` then refuses, the two have drifted and the
   highlighting is worse than none.
 
+**Done 2026-08-02.** From the live server: *"Solve onto problem 1"*,
+*"Investigate onto problem 2, problem 3"*, *"Attack onto P2, P3"*,
+*"Ground onto the table"*. The constant sentence is gone.
+
+`everything_the_page_advertises_actually_resolves` drives four real bot
+games and checks every emitted target against `resolve` itself. Mutation —
+adding `table` to Investigate's targets — goes red with *"the page
+advertises action-investigate -> table but resolve refuses it"*.
+
 ## Task: make picking up, dragging, and dropping visible
 
 ```task
 id: CB-WP-0017-T03
-status: todo
+status: done
 priority: high
 ```
 
@@ -149,11 +170,39 @@ The JS DOM stub cannot express any of this today. It will have to model
 and CB-WP-0016 showed that a stub too thin to express a failure is how the
 failure survives.
 
+**Done 2026-08-02.** `.pick` (resting shadow, lift on hover), `.held`
+(dimmed and scaled), `.dropok` (dashed outline on every legal target), and
+a ghost following the pointer.
+
+The stub now models `classList`, `querySelectorAll`, `createElement` and a
+body, **and its node set is built from the real emitted page** via
+`droppables(html)` rather than from a list the harness invented.
+
+Three mutations, each red:
+
+| mutation | result |
+|---|---|
+| the script *derives* targets from the DOM instead of reading `data-targets` | red — marks `seat-0, seat-1, seat-2` where only `seat-1` is legal. **A plausible-looking highlight, caught.** This is ADR-0010 D1 enforced |
+| the page advertises a target `resolve` refuses | red |
+| `pointercancel` and the `clear()` on pointerup are dropped | red — *"marks survived `__up('seat-1')`"* |
+
+**A seat highlights on both of its drawings** — card and graph node — and
+that is asserted rather than tolerated. The first draft of the assertion
+was wrong about it: it expected `seat-1` and read `seat-1,seat-1`.
+
+**A real trap, recorded:** QuickJS fixes its stack limit at `Context`
+creation relative to the frame it was created in, so a helper that creates
+a context and *returns* it makes every later `eval` report `SyntaxError:
+stack overflow` — for `__all.length`. The caller must own the `Context`.
+
+**Nothing perceptual is verified.** Whether a shadow reads as "pick me up"
+is not reachable from here (ADR-0010 D5).
+
 ## Task: evidence, and close the chaos calibration window
 
 ```task
 id: CB-WP-0017-T04
-status: todo
+status: done
 priority: high
 ```
 
@@ -184,3 +233,25 @@ Also due:
 - **Whether stage 1 closes.** It needs a human to drag again. Say so.
 - **Quote CB-WP-0016's cost**, and apply CB-EV-0013 §5's correction —
   quote a boundary that has actually settled, or say it has not.
+
+**Done 2026-08-02.**
+[CB-EV-0015](../evidence/CB-EV-0015-legible-interaction.md). `make all`
+exits 0.
+
+- **The chaos window's verdict: keep, at a lower rate.** Both overrides
+  changed the outcome, so the retirement condition is not met. CB-WP-0011
+  (L→S) bought a defect in the existing renderer that a toolkit survey
+  would have walked past, at 0.099 $/response against 0.123. CB-WP-0017
+  (S→M) bought the restatement of control 5 — at tier S the script would
+  have outgrown ADR-0007 D5 under a one-paragraph commit note.
+  **Recommendation: d4 → d8, second window of 12, retire if an override
+  changes nothing twice running.** That is a change to how the loop
+  constrains its own operation, so it is tier-M work this pass does not
+  do — it is owed to the next declaration.
+- **CB-EV-0014 is corrected.** It quoted CB-WP-0015 at $15.14/136 and
+  claimed that was the first settled figure this project had quoted. Both
+  wrong: it now reads **$22.70/166**. The number had been read during
+  CB-WP-0015 itself and carried forward, so there are two defects — the
+  boundary, and quoting a figure from memory rather than re-running the
+  instrument. Five for five, always low.
+- **Stage 1 stays open**, and now on a purely perceptual question.