[kyle-sexton]

Closes #8332

Summary

Adds plugins/planning/reference/design-principles.md, a bundled reference of foundational design principles that planning and implementation skills can read at design time. Each principle is one directive line cited to its defining canonical source, with an as-of date and a recheck trigger. Review-time checking of the same concerns stays with /review:quality-gate code-design, which the reference points at.

Fix

• New plugins/planning/reference/design-principles.md: SOLID, composition over inheritance, DRY of knowledge, coupling and cohesion, information hiding, deep modules, YAGNI's cheap-now test and reuse first. It applies to code, Markdown, skills and agent instructions, and a consumer's own standards override it.
• Sources are universal canonical primaries only; no org's own standards files are cited. Three secondaries appear, each labeled, where a book primary cannot be fetched.
• Changelog fragment under .changes/planning/ (minor bump).

Verification

• Phase verifier: 8/8 acceptance criteria passed.
• /review:quality-gate code-design resolves on main (landed in feat(review): add /review:quality-gate code-design mode #8388) after merging origin/main into the branch.
• bash scripts/check-affected.sh --tests --base origin/main: 7 passed, 2 skipped (no shell or Python changed).
• typos on the changed files: clean.
• No paid eval: this PR adds a reference file only. It is judged when its consumers (feat(planning): interview asks intent and quality requirements, reads consumer standards #8333, feat(planning): design defaults name the principles; add lifecycle and reversibility #8334, feat(planning): gate principle and reversibility threads at handoff, plan and plan-reviewer #8335) run their branch-vs-main evals.

Related

• feat(planning): carry universal, overridable design defaults through planning output #8326 (parent spec)
• feat(review): add /review:quality-gate code-design mode #8388 (adds the code-design mode to /review:quality-gate)

🤖 Generated with Claude Code

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-19T05:12:28.113435Z	f6b964b	Draft marked ready

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[github-actions]

claude-security-review reviewed f6b964be843048ca5c055e0921d31abdb51df09d: 0 finding(s), 0 as inline comments.

No security issues found in PR #8393 at head f6b964b.

The PR adds two files: a changelog fragment and plugins/planning/reference/design-principles.md. Both are documentation only. The diff has no executable code, workflow, hook, permission or config change, and no secrets or credentials.

The diff deletes, narrows or softens no standing instruction, so the instruction-surface lens found nothing to check against the exception register.

The new reference tells agents to apply a consumer's own standards over its defaults and to record the override. That is guidance for design-time defaults. It does not weaken any guardrail, and it gives no way to bypass a hook, a permission rule or a validator.

The external links are citations only. The file instructs no fetching and runs nothing from them.

[github-actions]

claude-review reviewed f6b964be843048ca5c055e0921d31abdb51df09d: 0 finding(s), 0 as inline comments.

No findings. I reviewed both changed files: the new plugins/planning/reference/design-principles.md and the changelog fragment.

Checked against #8332's acceptance criteria. I ran these checks myself:

• grep -c "melodic-software/standards" on the reference returns 0.
• grep -cE "^- \*\*(SRP|OCP|LSP|ISP|DIP)\*\*" returns 5.
• grep -c "; recheck when" returns 12, which meets the ≥ 11 requirement.
• The link target variation-points.md exists in plugins/planning/reference/.
• /review:quality-gate code-design resolves: plugins/review/skills/quality-gate/SKILL.md lists the mode.
• Cross-plugin citations use /plugin:skill form (/docs-hygiene:extract-ssot, /playbooks:skill-authoring, /docs-hygiene:write-for-agents), and the planning→review dependency direction holds.
• The two secondaries (composition over inheritance, coupling and cohesion) and the Rule of Three secondary are labeled, and they use the required "cited secondary moves or changes, or a recheck reaches the primary" trigger.
• The consumer-override line, scope line, reuse line and the Markdown pointers are present.
• The changelog fragment is in the planning plugin's .changes/ directory with a minor bump.

I did not independently verify the author's claimed phase-verifier, scripts/check-affected.sh and typos results. I also did not re-fetch the cited external URLs.

I found no closing-issue criteria that the change fails to meet, and no path-scoped rule that applies. The skill-bodies-state-current-rules rule covers only skills and agents, and this file is under reference/.