docs(knowledge): the judgment axis is knowledge, not a detector (B2)

Article rule 1 ("give Claude judgement instead of rules") gets its register
entry, and deliberately no detector. `BP-JUDG-001` carries `lensCheck: null`.

The cut between deterministic prefilter and prose judge was the open design
decision. It was settled by measurement, and the measurement declined both
halves:

- 409 real CLAUDE.md files (38488 lines, 8689 prose blocks): the caging class
  fires 7 times, and all 7 are false positives ("rendered prose-side",
  "naming is a flag on the class"). Verified along an independent grep path
  that bypasses block-splitting and sentence-splitting entirely, in both word
  orders: 5 lines and 1 line, none an instruction.
- The narrow variant (absolute + form noun + numeric cap) fired 8 times —
  one duplicated block seen seven times across plugin caches, precision 0 %.
  The pre-committed rule required 90 % over 20 distinct fires.
- Where the shape does occur — 45 lines across 4755 skill/agent/command files
  — it is the author's editorial policy (emoji, sentence length, slide
  titles). Nothing in the text separates that from a vendor's over-tight
  guardrail, and the article's reasoning does not transfer: the model is not
  the author of a user's config.

So no CA-OPT-002; finding-codes keeps OPT next-free = 2. The numbers live in
the entry's own `note`, so the next session does not re-derive the question.

Two premises the chunk falsified. The brief justified a separate axis by
saying these blocks sit inside `floor-exclusion`'s floor — but the article's
own canonical line carries no floor marker at all, so "inside the floor"
cannot define the axis (the corpus tendency is 76 %, which is a tendency, not
a mechanism). And the fasit's own form-noun vocabulary was wrong: `name` and
`format` alone drove 97 % of fires.

Not folded into `--subtract`: a third "loosen instead of delete" verdict in
the subtraction judge is the AS#5 mixing STATE forbids, and with the corrected
vocabulary there are 0 collisions to arbitrate anyway.

Guards, both seen red against their own defect first: the entry must exist,
be confirmed, date its source and name NO lensCheck; and every lensCheck in
the register must be backed by a real detector.

No behaviour changed — no new finding, no output change, nothing consumes the
entry yet — hence `docs`, not `feat`. Suite 1701 -> 1703/0; frozen v5.0.0 and
default-output baselines 0 changed files. Fasit:
docs/b2-judgment-lens-fasit.local.md

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_017mCkx9wGywqNQzsXkBMzJ1

knowledge/best-practices.json

@@ -263,6 +263,22 @@
           "note": "Verbatim: 'Claude will be more predisposed to double-checking additional hypotheses or verifying correctness at higher effort levels, but it generally won't artificially inflate usage for simple tasks at higher effort levels.'; 'In fact, our team pays close attention to \"overthinking\" during model training as it degrades effectiveness.'"
         }
       ]
+    },
+    {
+      "id": "BP-JUDG-001",
+      "claim": "An instruction that fixes a form decision — how code or prose should look (comment density, docstring length, naming shape, sentence or paragraph count) — as an absolute rule buys a guardrail current models no longer need, and is wrong for the cases the rule did not anticipate. Anthropic removed its own example from the Claude Code system prompt: \"Never write multi-paragraph docstrings or multi-line comment blocks — one short line max\" was replaced by \"Write code that reads like the surrounding code: match its comment density, naming, and idiom.\"",
+      "appliesTo": "claude-md",
+      "recommendation": "Where an absolute governs a form decision rather than a local fact, state the outcome you want and let the model judge the instance. This does not apply to safety rules, tool or version facts, or a house style you hold deliberately — those are the reason the claim is not machine-checkable.",
+      "confidence": "confirmed",
+      "category": "judgment-fit",
+      "lensCheck": null,
+      "note": "KNOWLEDGE ONLY — no detector, by measurement (docs/b2-judgment-lens-fasit.local.md §9). Across 409 real CLAUDE.md files (38488 lines, 8689 prose blocks) the class fired 7 times and all 7 were false positives; an independent grep in both word orders found 5 lines and 1 line respectively, none an instruction. Where the shape does occur — 45 matching lines across 4755 skill/agent/command files — it is the author's editorial policy (emoji, sentence length, slide titles), which nothing in the text separates from a vendor's over-tight guardrail. Precision-first: no CA-OPT code was allocated and OPT next-free stays 2.",
+      "source": {
+        "url": "https://claude.com/blog/the-new-rules-of-context-engineering-for-claude-5-generation-models",
+        "title": "The new rules of context engineering for Claude 5 generation models",
+        "published": "2026-07-24",
+        "verified": "2026-08-12"
+      }
     }
   ]
 }