SDPF Language Specification v1.3.1

SDPF is a formal specification language designed to produce complete, unambiguous specifications (called Technical Specification Prompts, or TSPs) for AI model consumption, eliminating the specification gaps that cause AI speculation. The language defines a mandatory Phase 0 — Problem Identification and Definition — before any specification work begins, ensuring problems are correctly identified, quantified, and validated against four tests before solutions are attempted. SDPF operates through three core principles: Specification First (no implementation begins until the contract is complete and locked), Facts Before Execution (all technical facts verified via the Technical Verification Gate before any work proceeds), and Verification Always (no release without a signed evidence package). The language encompasses a complete grammar defining a valid specification structure, a normative vocabulary of precisely defined terms, seventeen formally defined style dialects for different system types, a Conflict Resolution Protocol enforcing strictness-based precedence, and an eleven-check verification model testing structural invariants rather than surface form. By specifying what needs to be built from a validated problem statement — not what the AI should infer — SDPF shifts accountability entirely to the spec writer, making specification writing a mandatory professional skill rather than a creative afterthought, and proving that reliable AI output is achievable when specifications are complete, verifiable, and bounded by formal structural invariants.