SkillCheck Pro Changelog

v3.20.0 released April 2026

Cat 23: Agent Integration Readiness (MCP servers)

+ check-mcp CLI: validates an MCP server's tools/list response
+ 23.1 Free: tool-count thresholds (>20 high, >40 strong) and 1:1 CRUD-API mirror smell
+ 23.1-23.4 Pro: code-orchestration strength, identity-override critical, annotation completeness, CLI-literacy in descriptions
+ Schema-floor lock against modelcontextprotocol/servers reference shape

Cat 24: Skill Marketplace Governance (plugin manifests)

+ check-plugin CLI: validates .claude-plugin/plugin.json
+ 24.1-24.6 Free: name format, semver, required fields, command collision, layout
+ 24.4-24.5 Pro: change-gate evals pointer, maintainers field, deprecation block format
+ Schema-floor lock against anthropics/knowledge-work-plugins reference
+ Empirical benchmark: 21/21 reference plugins pass clean; 0/21 declare maintainers or evals

Cat 25: Memory Governance (design)

+ Six primitives from Anthropic Managed Agents memory release: scoped permissions, audit logs, rollback, redaction, concurrent access, observable session events
+ Two-stage activation rule: skills not declaring memory usage report "not applicable" rather than scoring zero
+ Implementation pending first-party memory-using exemplar skills

Browser validator

+ Three-tab input selector (SKILL.md, plugin.json, tools/list) on validate.getskillcheck.com
+ All checks run client-side via WebAssembly

Sources: Anthropic Production MCP patterns, Sam Morrow's four axes, knowledge-work-plugins, Anthropic Managed Agents memory.

v3.19.0 April 2026

Anti-Slop Expansion (Pro)

+ 5.3 Verb inflation: flags "serves as a", "stands as a", "functions as a" when "is" or "has" works
+ 5.3 Promotional adjectives: catches vibrant, groundbreaking, cutting-edge, and 5 more travel-brochure words in skill text
+ 5.3 Vague attributions: detects "experts say", "industry reports suggest" without named sources

115 total checks across 22 categories.

v3.18.0 April 2026

Knowledge Density (Free + Pro)

+ 22.7 Hollow content detection (Free): flags gotchas/troubleshooting sections with 3+ generic filler phrases and no concrete knowledge signals
+ 22.1-22.6 Density strengths (Pro): rewards specific thresholds, consequence explanations, experience markers, debugging sequences, decision logic, and concrete code references
+ Code block, frontmatter, and table header exclusion for all density scanning
+ Based on anti-distill classifier inversion: six categories of high-value tacit knowledge

112 total checks across 22 categories. Sources: colleague-skill (7.8k stars), anti-distill (800 stars).

v3.17.0 April 2026

Eval Kit Generation (Pro SKILL.md)

+ 21.1-21.3 Should-trigger prompts: generates explicit, implicit, and contextual test prompts from the skill's description and trigger words
+ 21.4 Negative control prompts: generates should-NOT-trigger prompts from trigger collision data and boundary sections; names which skill each negative belongs to
+ New Phase 5 in validation pipeline appends Eval Kit to every Pro report
+ Copy-pasteable prompts for manual skill verification in Claude Code

109 checks across 21 categories. Sources: OpenAI eval-skills methodology.

v3.16.0 April 2026

GitHub Actions Integration (Pro)

+ Reusable composite action: validate skills in CI with uses: olgasafonova/skillcheck@v3
+ Configurable fail thresholds: critical, warning, or none
+ Structured outputs: score, grade, result, critical/warning/suggestion counts
+ Pro license support via GitHub secrets

105 total checks across 20 categories.

v3.15.0 March 2026

Design Pattern Classification (Free + Pro)

+ 19.1 Pattern detection (Free): classifies skills as Reviewer, Generator, Inversion, Pipeline, or Tool Wrapper based on the Google ADK taxonomy
+ 19.2-19.7 Pattern deep checks (Pro): validates pattern-specific requirements; criteria for Reviewers, output specs for Generators, question frameworks for Inversion, stage docs for Pipelines, API boundaries for Tool Wrappers

Artifact Contract Validation (Pro)

+ 17.6-17.9: validates produces/consumes frontmatter fields, artifact metadata documentation, and discovery patterns
+ Flags undeclared artifact type references in body text (with code block exclusion to prevent false positives)

Trigger Collision Detection (Pro)

+ 20.1-20.4: cross-skill directory scan using Jaccard similarity on trigger word sets; flags overlaps at 50% (warning) and 85% (critical)
+ 20.5-20.7: artifact pipeline validation; detects orphan producers and missing consumers across skill directories
+ Runs automatically during skillcheck scan

105 total checks across 20 categories. Sources: Google ADK skill design patterns, Anthropic skill taxonomy.

v3.14.0 March 2026

New Free Tier Checks

+ 4.8 Description trigger style: flags descriptions that read as capability summaries instead of trigger conditions
+ 4.9 Railroading detection: catches 5+ prescriptive phrases that reduce Claude's adaptability
+ 8.9 Gotchas section: recognizes gotchas/pitfalls/caveats documentation as a quality strength

New Pro Tier Checks

+ 10.7 Setup/config handling: flags skills referencing credentials without handling missing-config case
+ 10.8 Data storage path safety: warns about persistent data stored inside skill directory (won't survive upgrades)

87 total checks. Source: Anthropic's internal skill design insights.

v3.13.0 March 2026

New Frontmatter Fields

+ effort field validation (low, medium, high)
+ maxTurns field validation with runaway detection (>100)
+ disallowedTools validation with allowed-tools overlap detection
+ Model aliases accepted: opus, sonnet, haiku
+ Spec version updated to 2026-03-20

v3.12.0 March 2026

Skill Discovery

+ skillcheck discover CLI command and skillcheck_discover MCP tool
+ Multi-platform scanning: Claude Code, Cursor, Windsurf, Codex CLI
+ Scans CLAUDE.md, .cursorrules, AGENTS.md, custom commands, hooks
+ Confidence scoring (HIGH/MEDIUM/LOW) per candidate
+ Platform auto-detection with per-candidate tagging
+ Redundancy detection across config files
+ Free: see candidates. Pro (--generate): auto-create SKILL.md files

v3.11.0 March 2026

Anti-Pattern Detection

+ 4.7-desc-workflow-steps (Free): flags descriptions that summarize workflow steps
+ 12.5-no-exit-criteria: phased skills missing exit criteria per phase
+ 12.6-unbounded-iteration: catches unbounded "for each" loops
+ 15.6-subagent-no-return-format: subagent prompt checks
+ 12.7-verbosity-detection: flags unnecessary explanations of well-known concepts
+ 12.8-feedback-loop-detection: flags quality-critical skills lacking verify steps
+ Skipped checks shown as "not applicable" instead of silently omitted
+ Accurate passed count: "Passed: N / M applicable"

v3.10.0 March 2026

Agent Readiness (L0-L3)

+ 6 new validation pillars with 28 checks (prefixes 13-18, Pro tier)
+ Reference Integrity: dangling references, excessive count, organization
+ Eval Readiness: success criteria, input/output examples, binary verdicts
+ Orchestration Safety: budget caps, phase boundaries, human checkpoints
+ Autonomy Design: stop conditions, safety guardrails, rollback, idempotency
+ Composability: input/output contracts, mode awareness, interface sections
+ Observability: progress reporting, confidence levels, phase boundaries
+ L0-L3 maturity scoring for agent-ready skills
+ WASM web validator at validate.getskillcheck.com
+ 82 total checks across 18 categories

v3.9.0 March 2026

Claude Code v2.1.69-71 Sync

+ New tools in KnownTools: CronCreate, CronDelete, CronList, EnterWorktree
+ Quality check 8.8-uses-skill-dir-var for ${CLAUDE_SKILL_DIR}
+ Example XML block tracking in ambiguous term and wisdom checks
+ Description severity softened from required to recommended
+ Version moved from top-level to metadata block

v3.8.0 March 2026

Wisdom Detection & Format Lint

+ 4.6-wisdom-platitude (Free): detects generic advice that wastes tokens
+ 2.8-anti-pattern-format (Free): flags prose anti-pattern docs, suggests tables
+ Progressive disclosure via references/ directory

v3.7.0 March 2026

Progressive Disclosure & Skill Sync

+ SKILL.md uses references/ for context-efficient loading
+ Version sync across CLI, MCP server, and web server

v3.6.0 February 2026

Anthropic Guide Alignment

+ Aligned with "The Complete Guide to Building Skills for Claude" (Anthropic, Feb 2026)
+ 4.4-body-misplaced-routing: flags "When to Use" sections in body
+ Routing trigger content moved to description field