Python arch-gate (import-linter)

REFERENCE MODE: This skill provides reference material for the Python domain's arch-gate binding. It is a thin pointer — the structural concept, the read-only contract, the execution model, and the findings → triage → lesson feedback loop are owned by the central standard and MUST NOT be duplicated here.

The single authoritative model for arch-gate lives in arch-gate-fitness-functions.md in plan-marshall:manage-architecture. Read that document for what an architectural fitness function is, the read-only structural-boundary-gate contract, the single per-deliverable execution model, resolution/execution path, and the lesson lifecycle. This skill carries only the Python-specific binding.

Enforcement

Execution mode: Reference library; load for context when running or interpreting the Python arch-gate. Never execute this document's content as a workflow.

Prohibited actions:

• Do not duplicate the central arch-gate-fitness-functions.md model here — this skill is a thin pointer
• Do not mutate source from the arch-gate run — it is read-only with respect to both source and the lessons corpus
• Do not conflate the whole-graph import contract with per-file ruff — import-linter asserts a property of the import graph, not per-file style

Constraints:

• The Python arch-gate tool is import-linter; the descriptor the extension declares is {'tool': 'import-linter'}
• arch-gate runs as a per-deliverable read-only verify-step resolved through architecture resolve --command arch-gate
• A structural-boundary violation is typed as an arch-constraint finding, never a generic lint-issue