Spec Fidelity Gate

A triage gate between requirement formalization and agentic synthesis that halts execution if specification completeness or consistency falls below safety thresholds.

In the SDAD-V lifecycle (a phase-latency-compressed descendant of the classic V-model), development descends from stakeholder intent through formalization until reaching the vertex: the spec fidelity gate. This gate serves as the formal boundary between human architectural intent and autonomous code synthesis. When implementation is generated rather than hand-written, the specification's quality is the ceiling on the product's quality: every gap is executed literally.

Before invoking zero-shot repository synthesis under agentic linearism, the gate audits the formal specification against four named spec fidelity checks:

  1. Completeness — edge cases and failure modes are explicitly documented.
  2. Consistency — the requirements contain no internal contradictions.
  3. Unambiguity — each requirement admits exactly one stable interpretation.
  4. Verifiability — each requirement maps to an automated test with an objective pass/fail criterion.

The audit ends in an explicit triage decision:

  • Pass to synthesis: If the specification meets completeness, consistency, and verifiability thresholds (e.g., above the 70% clarity threshold under the ambiguity tax), execution proceeds directly to autonomous multi-file generation.
  • Refine specification: If syntax or internal contradictions are detected, the orchestrator routes the specification back to formalization agents for automated schema repair and alignment.
  • Request stakeholder clarification: If domain rules or business intentions are missing or fundamentally ambiguous, synthesis is halted to solicit human intervention via iterative refinement feedback channels. This branch matters most: it routes ambiguity back to the only party able to resolve it, instead of letting the generator silently pick an interpretation.

By strictly gating entry into the autonomous build phase, the spec fidelity gate prevents costly generation passes on flawed blueprints and bounds downstream verification failures. Because the pipeline executes intent strictly as written, ambiguous requirements otherwise produce strategically wrong artifacts that survive until a downstream gate catches them, if any does. Checkable requirements are what make that downstream verification possible; keep the verifier independent of the generator per the model-family independence rule.

Sources

  • Nguyen & Nguyen (2026), ch. 8 (§7.3)