feat(kyberforge): improve agent-audit skill with platform-accurate checks and description quality reference

- Fix validate.sh: remove incorrect name==stem check for CC files (CC docs say filename need not match name field); keep check for Copilot CLI only
- Fix validate.sh: plugin scope detection now checks both plugin.json and .claude-plugin/plugin.json
- Fix validate.sh: Copilot cloud/IDE agents (.github/copilot/agents/) have name as optional; path-based guard added
- Add validate.sh checks: Copilot body length >30,000 chars (SUGGESTION), Copilot-only fields in CC files (FAIL), subagent-unavailable tools in tools field (SUGGESTION)
- Add references/description-quality.md as conditional escape hatch for borderline description findings
- SKILL.md: name five audit dimensions in description; sharpen indirect-trigger phrasing
- SKILL.md: label pair-mandate as kyberforge project convention, not platform requirement
- SKILL.md: scope redundant name-match/body-empty checks to manual fallback only
- SKILL.md: add conditional reference to description-quality.md; update provider-safety description for new check categories; fix plugin scope gotcha to mention .claude-plugin/plugin.json
- SKILL.md: add INFO tier to result block template
- Add source_keys frontmatter to references/README.md; update sources.md to add description-quality.md to contributing files

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0147vXtL5sP6vorDdqXGJJU9

plugins/kyberforge/skills/agent-audit/references/description-quality.md

@@ -0,0 +1,49 @@
+---
+source_keys:
+  - context7-websites-code-claude
+  - claude-code-plugins-docs
+  - claude-code-subagents-docs
+  - context7-github-en-copilot
+  - github-custom-agents-configuration
+---
+
+# Agent Description Quality Reference
+
+Load this file when a description finding is borderline and you need to make a precise call.
+
+## Action-verb opening
+
+The description must open with an imperative or present-tense verb that describes what the agent does ("Reviews...", "Audits...", "Generates...", "Analyzes..."). Avoid:
+- Noun phrases: "An agent that..." — no verb
+- "This agent..." or "Use this when..." — passive framing
+- "Helps with..." — too vague to be a clear verb
+
+**Borderline call:** "Validates and reviews..." is acceptable — two verbs is fine if both are specific. "Assists in reviewing..." is not — "assists" is vague filler.
+
+## Specificity of trigger condition
+
+The description must state what specifically triggers the agent. Generic phrasing fails:
+- Too vague: "when the user needs help with agents"
+- Acceptable: "when the user says 'audit this agent', 'check if my agent follows best practices', or wants to know if an agent pair is ready to ship"
+
+Include indirect triggers: "even if they don't use the word 'audit'" or "even if the user doesn't phrase it as a review request". If the agent should activate on a recognisable user goal (not just literal keyword matches), name that goal.
+
+**Borderline call:** If the description covers direct triggers but omits common indirect phrasings that a user would plausibly use, mark as SUGGESTION (not FAIL) — the agent still activates, just less reliably.
+
+## `Use proactively`
+
+For CC files: including "Use proactively" signals the CC runtime to offer the agent unprompted when conditions are met. This is CC-specific — use it when the agent should activate without an explicit user request.
+
+For Copilot files: this phrase has no effect. Use `user-invocable: false` / `disable-model-invocation: true` for equivalent Copilot behavior. Flag `Use proactively` in a Copilot description as a SUGGESTION (not FAIL) — it causes no harm, just has no effect.
+
+## Length and hard limits
+
+- CC agent descriptions: no documented character limit, but keep under 500 characters to avoid truncation in UI contexts.
+- Copilot agent descriptions: no separate documented limit, but the overall 30,000-character body limit applies to the full file.
+- Skill descriptions (SKILL.md): hard 1024-character limit enforced by the platform.
+
+## Do not use when
+
+Include a "Do not use when..." clause only if a near-miss agent or skill exists that could steal activations. Omitting it is not a finding. Including it is correct when there is a real confusion risk (e.g., `/agent-audit` vs `/skill-audit`).
+
+**Borderline call:** If the "Do not use when" clause is present but the exclusion described is already obvious from context, mark as SUGGESTION to tighten or remove — not FAIL.