Decision: no agent-facing view-model endpoint; one shared presenter plus a CLI entrypoint instead

Elazar 2026-09-08 02:28 proposed a DEV-only read-only endpoint returning the resolved view model for a page as JSON, so lanes assert on values instead of pasting DOM. Blackboard bb-coder02-mba-l-cc-mts8dkh6 asked coder-mba-l-ca, db02-mba-l-cc, db03-mba-l-ca and proxy-mba-w-cc independently. VERDICT: do not build the endpoint. Four independent answers converged. (a) Token saving is unproven: only proxy could name real exchanges (PMI009/AA033TK innerText captures hitting truncation, 3-4 follow-up calls), and proxy also disclosed it never loaded the get_page_text tool already available to it, which may remove most of that cost with zero new surface. (b) A view model computed by any path other than the page's own is a SECOND IMPLEMENTATION: two implementations agreeing is not evidence about the screen, same failure shape as dev and prod agreeing while both diverge from the book. (c) It structurally cannot answer the class of bug it was pitched for: 337 (blank form before loads finished) and 339 (click delivering zero DOM events) are timing and event failures, and a JSON fetch has no timing, so it would report healthy values for a blank screen. That sentence must accompany any future revival. (d) No HTTP route is structurally excludable from prod: DEV runs production builds, so a NODE_ENV or hostname guard is one env var from live, and it would dump catalog-resolved business data. INSTEAD, three cheaper things, in order: (1) ONE shared pure presentation derivation that the page and any check both call, no re-derivation, owned by the coder lane in this repo (coder-mba-l-ca is already extracting it for MOVILBA-343); (2) diagnostic access to it as a CLI/test entrypoint under tools/, never a deployed route; (3) proxy tries get_page_text first, plus semantic data-history-field/data-history-surface markers so the browser can return a compact value table instead of raw DOM. Revisit only with a measured failure of all three, not on a hunch.