Build Log

Arc Intelligence — The Classifier, Built for Real

July 18, 2026

Corrected the product-vs-microscope confusion the prior session's own stall surfaced, ran the pivot through the Crucible, then built (not prototyped) the missing Arc Interpretation layer end-to-end — a 4-axis classifier, deterministic derivation, append-only Smith review, and a dual JSON+HTML surface — and proved it against the one real transcript in the repo.

ForgeKit OSArc IntelligenceProduct PivotClassifier

new tests written, all passing (88/88 total across npm run test:os after this session)

real session classified end-to-end against actual transcript evidence (arc-slice-transcript-adapter-2026-07-18 — the only session in the repo with a resolvable transcript_reference)

distinct classification axes (lifecycle phase, mechanism, event, condition) — replacing an original flat 6-value enum plan before any classifier code was written

Timeline

Start

Zeb delivers the corrected Charge

Evidence/audit infrastructure from the last several sessions is the microscope, not the product. Arc Intelligence — classifying sessions at the Arc-step level — is the actual product.

+10m

Scoping question asked and answered

Asked whether to build a narrow proof, a design-only pass, or something else; Zeb: 'no clumsy POC or thought exercise... we build at ForgeKit'

+20m

Crucible run — architect/qe/steward converge

All three flagged the same gap: classification accuracy is unproven and must be validated against real data with a manual review path built in from day one, not deferred

+25m

Charge synthesized, scoping question asked

Proposed terminal/JSON output vs. HTML ribbon as the first validation surface

+30m

Zeb delivers the ontology correction

Rejects the flat 6-value arc_step enum outright — specifies 4 independent axes (lifecycle phase, mechanism, event, condition) matching Alloy's real Forge Arc Rail vocabulary, plus a full JSON contract, review-event model, and Arc Trace ribbon design spec

+45m

taxonomy.mjs written

Single source of truth for all 4 axes — every other module imports vocabulary from here, no hardcoded string literals elsewhere

+70m

classify.mjs written

Turn-level batched LLM classifier reusing buildArcPreview's turns[] unchanged; structural sanitizeUnit() validation drops any out-of-taxonomy model output rather than accepting it

+90m

derive-arc-trace.mjs + review.mjs written

Pure deterministic derivation (proposal + append-only reviews -> phase segments/mechanism spans/condition spans/events); computeEffective never mutates the original proposal

+110m

render-arc-trace.mjs written

Multi-lane HTML ribbon with zero independent classification logic — every label traced back to derive-arc-trace.mjs's output

+120m

npm scripts wired, 35 tests written and passing

arc:classify / arc:render commands added; contract tests (4-axis separation, Strike-as-event-not-phase), derivation tests (segment merging, review application, backward transitions), renderer tests (determinism, no-raw-text, non-color-only encoding)

+130m

Searched the whole repo for a real transcript_reference to test against

Only arc-slice-transcript-adapter-2026-07-18 qualifies among all 159 sessions — a 4-turn sample, thin but real

+140m

Ran the classifier for real, rendered the HTML, published it as an artifact

Flagged honestly in the artifact itself that this is a thin sample and named the one result worth scrutinizing (no Forge phase detected despite that session's retro describing real build work)

+150m

Zeb validates: 'yes, this looks good. proceed'

Real sign-off on real output, closing the build-test-validate loop exactly as instructed

What shipped

forgekit-os/scripts/arc/taxonomy.mjs — the corrected 4-axis vocabulary (lifecycle phases, mechanisms, events, conditions), single source of truth for every other Arc Interpretation module

forgekit-os/scripts/arc/classify.mjs — turn-level classifier: batches a session's turns (from the already-proven buildArcPreview) into one structured OpenAI call, returns phase/mechanism/event/condition proposals with confidence, structurally sanitizes any out-of-taxonomy model output rather than trusting it

forgekit-os/scripts/arc/derive-arc-trace.mjs — pure, deterministic derivation from {classifier proposals, append-only review events} into phase_segments/mechanism_spans/condition_spans/events/transitions/session_summary. No I/O, no re-classification — same input always produces the same output

forgekit-os/scripts/arc/review.mjs — append-only Smith review event construction/storage; a review event can never overwrite a proposal, only add to the record computeEffective reads

forgekit-os/scripts/arc/render-arc-trace.mjs — HTML renderer with zero independent classification logic; every visual element carries machine-readable data-* attributes

forgekit-os/scripts/arc/build-classification.mjs — orchestration entry point: resolves a session's transcript_reference, classifies, writes the canonical forgekit.arc-interpretation.v1 JSON

npm run arc:classify / npm run arc:render — CLI commands

35 new tests across 4 files (contract, derivation, sanitization, renderer determinism) — all passing alongside the existing 53 (88/88 total)

forgekit-os/arc-interpretations/arc-slice-transcript-adapter-2026-07-18.json — the first real, committed Arc Interpretation output

A polished HTML Arc Trace artifact, reviewed and confirmed by Zeb against the real session

“we build, we test, I validate then we revisit”
— Zeb, setting the actual loop this session followed