[maxmad64bis]

Summary

• The Auto-Combo engine was described as 6-, 9-, 13- and 14-factor in seventeen places while DEFAULT_WEIGHTS declares fifteen factors. Two of the fifteen sit at weight 0 by default, which is where some lower counts came from, but they are computed for every candidate, and cacheAffinity gates prompt-cache deduplication outside the score — they are declared factors that do not vote by default, and AUTO-COMBO.md now says exactly that.
• Instead of hand-fixing seventeen numbers, check:docs-counts grows a strict check that reads the count from scoring.ts and validates every N-factor claim across README, AGENTS.md, guides, diagrams and code comments. Adding a factor without updating the prose now fails CI. CHANGELOG.md is deliberately out of scope: old entries record what was true when they were written.
• The strategy description string in routerStrategy.ts stops hard-coding an enumerable count ("15-factor weighted scoring (see DEFAULT_WEIGHTS)") so there is one fewer derived number to keep in sync.

Related Issues

• None. Nothing open upstream on this topic at the time of writing (checked via issue search).

Validation

• Change type: routing / docs
• Focused tests and category gates from the golden path: check:docs-counts fails on the pre-change tree and passes after (verified in that order, otherwise the gate proves nothing); counting-helper unit tests pass
• npm run lint

Local caveat: my machine's node_modules is broken (es-abstract incomplete) and a borrowed install carries a newer eslint-plugin-react-hooks than this branch's lockfile pins, which produces results that do not match CI. The only file my scoped run flagged is free-provider-rankings/page.tsx, untouched by this PR. CI is authoritative.

• Reconciled with the current active release base; focused checks rerun afterward
• Production-code changes include a new or updated automated test in this PR (the new gate check and its counting helper are covered in tests/unit/check-docs-counts-sync.test.ts; code-comment strings are covered by the same gate)

Tests Added Or Updated

• tests/unit/check-docs-counts-sync.test.ts — counting helper handles zero-weight factors, comment noise and unreadable sources; drift detection proven.
• Existing lkgp-enabled-context-11181.test.ts and combo-matrix/auto.test.ts updated only where they quoted a stale factor count in a string.

Coverage Notes

• Logic added lives in scripts/check/check-docs-counts-sync.mjs (build tooling) and is covered by the unit test above; runtime routing code changed only in doc-facing strings.

Reviewer Notes

• The gate is strict on purpose: it reads the canonical count from source, so prose cannot drift silently again.
• Unit suite on this exact base is currently red for an unrelated reason (159 vs 160 migrations). Fixed by the sibling PR docs/migrations-count-160 — merging that one first keeps this PR's CI green.