msd-core/docs/features/spec-phase-edge-completeness-probe.md

id, title, group

id	title	group
144	Spec-Phase Edge-Completeness Probe	v1.42.1 Features

Command: /gsd-spec-phase

Purpose: Surface the omitted domain-boundary edges that silently invalidate a requirement — touching intervals, empty inputs, rounding ties, grapheme truncation — before they become production defects. Runs as Step 5.5 of spec-phase, after the ambiguity gate.

Behavior: For each SPEC requirement the probe classifies its data/behavior shape, then raises only the applicable categories from a closed 8-category taxonomy (boundary, adjacency, empty, encoding, ordering, precision, idempotency, concurrency) via a relevance filter. Each raised category proposes one concrete candidate edge, which the author resolves to exactly one of four states:

State	Meaning	Downstream effect
covered	An acceptance criterion handles the edge	Pass/fail line written into the SPEC Acceptance Criteria block; lifted into plan-phase must_haves.truths
dismissed	The edge cannot occur (requires a non-empty reason)	Recorded with its reason; empty dismissals are rejected
backstop	Intent recorded, needs a held-out/property-based test	Lifted into must_haves.truths as a non-inferable check
unresolved	Deferred	Soft-gates the spec; row stamped ⚠ Edge unresolved — planner must treat as assumption

When a requirement's prose matches no shape cue, the probe does not silently drop it (#1110): it emits a single unclassified — review manually candidate so the zero-cue requirement is surfaced for the author to resolve like any other (specify / dismiss-with-reason / defer) — a manual-review nudge, not a hard block.

Non-English projects: the probe reads English via text_en, the SPEC does not have to (#2773, durable fix #3717). The shape cues are English word-boundary patterns, so a project running with response_language set would otherwise have every requirement match nothing, classify to zero shapes, and land in unclassified — the taxonomy silently contributing nothing to exactly the kind of spec it exists to harden. spec-phase Step 5.5 therefore populates an optional text_en field alongside each requirement's text with a faithful English translation: text_en is engine input, never user-facing output, so it is translated while text keeps the requirement's own wording (the SPEC stays in the original language), requirement ids are left untouched, and any acceptance criteria written back from the resolved edges return to response_language. Translation makes the classifier applicable; it does not make it omniscient. A requirement carrying no shape cue in any language still classifies to zero — that is the classifier's recorded recall gap (ADR-857 §98), not a translation failure — and the remedy there is the same one an English project uses: author an explicit shapes array on the requirement instead of relying on prose classification.

The resolved edges populate a ## Edge Coverage section in SPEC.md. Unresolved applicable edges trigger a soft gate (Resolve / Write-anyway-flagged / Keep-probing) rather than a hard block. Under --auto, the probe never auto-dismisses — it auto-covers where a defensible criterion exists, otherwise auto-backstops, and logs [auto] edge coverage: C covered, B backstop, U unresolved. The one exception is an unclassified candidate: --auto leaves it unresolved (surfaced as a flagged assumption), never auto-backstop — a missing shape is not evidence an edge exists, so minting a held-out edge obligation would be a false claim.

The load-bearing wire is the plan-phase lift: covered and backstop edges become must_haves.truths the verifier can check, so the section is not merely documentation. A backstop edge is lifted as a structured non-inferable marker ({ statement, verification: backstop }, a flat scalar — not a prose note), which the honest verifier then consumes (see below) — closing the loop the edge-probe opened.

Honest verifier — abstention on non-inferable checks (#1154). A non-inferable (backstop) truth is one whose correct behavior is not derivable from the spec alone, so the verifier cannot self-detect the gap and would confidently false-pass it (~100% of the time). At verify time, a backstop truth the verifier cannot confirm with explicit evidence (a passing wired held-out/property-based test, or a directly-observed behavior) abstains → human_needed with reason insufficient_spec (reported as unverified — held-out test recommended), never a silent passed. This is the verify-time, truth-axis mirror of the prohibition judgment-tier disposition (ADR-550 D4): exogenous (driven by the backstop tag, never a self-judged "abstain if unsure"), routing-not-diagnosis (the held-out test carries the omitted rule), and capable-tier dependent (reliable on sonnet+; the budget haiku tier degrades toward current behavior). An inferable truth is never abstained (the over-abstention guard). Reference: Honest Verifier.

Requirements:

• REQ-EDGE-01: The edge pass MUST run after the ambiguity gate and emit a ## Edge Coverage SPEC section.
• REQ-EDGE-02: The relevance filter MUST raise only applicable categories; each raised edge resolves to exactly one of covered/dismissed/backstop/unresolved.
• REQ-EDGE-03: A dismissed resolution MUST require a non-empty reason.
• REQ-EDGE-04: An unresolved applicable edge MUST trigger the soft gate; write-anyway stamps the row as a planner assumption.
• REQ-EDGE-05: --auto MUST never auto-dismiss — auto-cover or auto-backstop only.
• REQ-EDGE-06: plan-phase MUST lift covered criteria and backstop notes into must_haves.truths.
• REQ-EDGE-07: A requirement whose prose matches no shape cue MUST surface an unclassified — review manually candidate (never silently dropped); --auto MUST leave it unresolved, never auto-backstop.
• REQ-EDGE-08: plan-phase MUST lift a backstop edge into must_haves.truths as a structured flat-scalar marker ({ statement, verification: backstop }), never a prose parenthetical.
• REQ-HONEST-01: At verify time a backstop truth that cannot be confirmed with explicit evidence MUST abstain → human_needed (reason insufficient_spec), never passed; an inferable truth MUST never be abstained (over-abstention guard); abstention MUST be exogenous (driven by the backstop tag, not self-judgment).

Reference: Edge Probe