chore: re-audit unused skills before source cleanup

[ClaudiaFang]

Context

The original cleanup list came from a /doctor snapshot covering only the previous 4 days / 10 projects / 50 sessions at that point in time. That snapshot is useful historical evidence, but it is not a durable basis for deleting skills months later because agent workflows and repositories continue to change.

Some listed skills were already removed or disabled elsewhere; the remaining source cleanup must be based on a fresh audit, not the old zero-usage counts alone.

Goal

Remove or consolidate genuinely unused skills without deleting capabilities that have become active again or are referenced by current repositories.

Required revalidation

Before deleting any skill from firstsun-dev/skills:

• Run a fresh /doctor / skill-usage audit across the currently active projects and recent sessions.
• Search current repositories for explicit references to the candidate skill name/path.
• Check whether the skill is installed, overridden, or intentionally disabled in active project configurations.
• Distinguish unused, replaced by another skill, and low-frequency but intentionally retained.
• Record replacement/migration target when a skill is removed because another skill supersedes it.

Historical candidates

The previous audit identified these groups; treat them as candidates to recheck, not automatic deletions.

Previously removed in downstream/project copies

• documentation-writer
• healthkit
• rust-backend
• d1-drizzle-schema
• devops-engineer
• github-actions
• internationalization-i18n
• monorepo-management
• owasp-security
• react
• react-best-practices
• vercel-react-best-practices

Previously disabled via overrides

• agents-sdk
• cloudflare-email-service
• durable-objects
• sandbox-sdk
• web-perf

Historical reference: firstsun-dev/innovation-apps#57.

Acceptance criteria

• Every deletion is supported by a fresh usage/reference audit.
• No current CLAUDE.md, AGENTS/config file, or active project points to a deleted skill.
• Superseded skills identify their maintained replacement where applicable.
• The cleanup reduces duplicate/dead skills rather than merely mirroring an old local override list.

[ClaudiaFang]

Backlog priority review — 2026-08-04

Priority: P2

Reason: Removing unused skills can reduce agent context noise and maintenance, but the evidence covers only a short observation window and zero recorded use does not prove a skill has no future or specialized value.

Scheduling note: Re-run the audit over a longer window, check dependencies/references and replacement coverage, then remove in small batches with validation. Archive or deprecate uncertain skills before permanent deletion.