What problem does it solve? Python/ML sidecars often gain direct access to databases, caches, and queues through drivers and connection URLs, creating a large security blast radius when fast-churning ML dependencies are compromised. This Skill enforces an architectural invariant where the Python tier is compute-only and reaches persistent data exclusively through a strongly-typed service tier over a typed contract wire. ## Core Features & Use Cases - Invariant Definition: Defines the non-negotiable rule that Python/ML sidecars must not hold credentials, import data-store drivers (psycopg, asyncpg, sqlalchemy, redis, kafka, pymongo), or read infra connection URLs (DATABASE_URL, REDIS_URL, RABBITMQ_URL). - Two Sanctioned Transports: Supports both service-gated (HTTP with protobuf-only bodies) and bus-gated (message-bus typed payloads) realizations without mandating one. - Guard Enforcement: Specifies a python-compute-only-guard with three static scans (forbidden drivers, infra URL reads, REMOVED-marker persistence) wired into pre-push and CI with no bypass flags. - Audit Checklist: Provides a 7-step agent-runnable audit covering driver scans, env-delivery checks, transport posture, and conformant-by-architecture N/A decisions. - Use Case: When reviewing a new embedding service, run the audit checklist to confirm it imports no database drivers, receives no infra URLs in its environment, and communicates with the Rust/Go service tier only via protobuf messages. ## Quick Start Audit my Python ML service to verify it holds no database credentials or drivers and reaches data only through the typed service tier.
