chore: suppress ARC-004 (API Contracts) — N/A for markdown plugin

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Quality Gate Reference

• Checklist Item: ARC-004 (API Contract Design)
• Current Score: 0.35/1.0
• Impact: High — blocks Tier 1 floor (0.5 minimum)
• Effort: Low

Description

ARC-004 checks for formal API contracts (OpenAPI, JSON Schema, Protocol Buffers). This Claude Code plugin's interface is markdown files (agents/.md, skills//SKILL.md) consumed by Claude Code's runtime — not HTTP endpoints or programmatic interfaces.

The correct action is a documented suppression: "Plugin interface is defined by markdown file conventions per Claude Code plugin spec; no programmatic API surface exists that would benefit from OpenAPI/JSON Schema contracts."

Optionally, add a PLUGIN-SPEC.md documenting the expected markdown structure as a lightweight contract.

Acceptance Criteria

• ARC-004 suppressed in .cogitations/config.yaml with justification
• Tier 1 floor no longer blocked by ARC-004
• Optional: PLUGIN-SPEC.md documenting markdown file conventions

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ARC-004 is already suppressed in .cogitations/config.yaml (line 86-88) with justification: "Plugin interface is markdown files per Claude Code plugin spec — no programmatic API surface requiring OpenAPI/JSON Schema contracts"

This was added as part of the initial cogitations configuration. The Tier 1 floor is no longer blocked by ARC-004.

Closing as already resolved.