feat: improve skill scores for cortexdb

[rohan-tessl]

Hey 👋 @liliang-cn

I ran your skills through tessl skill review at work and found some targeted improvements.

Here's the full before/after:

Skill	Before	After	Change
cortexdb	83%	94%	+11%

Changes made

• Progressive disclosure: Moved the large monolithic API reference (~200 lines) to concise sections with a pointer to docs/ for full details — the main SKILL.md is now focused and scannable
• Added validation checkpoints to the end-to-end workflow: Step 4 now verifies document count before searching, and Step 5 checks for empty results with a fallback hint — giving the AI agent clear retry paths
• Added a "When to Use What" routing table at the top so the agent can instantly select the right API (Quick vs InsertText vs InsertTextWithVector vs Knowledge/Memory/GraphRAG)
• Removed redundant concept explanations (e.g., "Store and search embeddings (vector representations of data)") that Claude already knows — keeping only actionable, copy-paste-ready code

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⚡ Your skills could self-improve on every PR

Right now, skill quality depends on whoever has time to run a manual review. It doesn't have to work that way.

tesslio/skill-review-and-optimize is a free GitHub Action that turns every PR into an automatic skill quality check — with AI-powered rewrites ready to merge in one click.

Here's what happens the moment you add it:

Without the Action	With the Action
Skills drift in quality between manual audits	Every PR gets an instant quality score
Contributors guess whether their edit is an improvement	AI feedback lands in the PR comment before review
Fixing a bad skill means a separate PR, separate effort	Comment /apply-optimize → improvement committed automatically
Quality depends on who has bandwidth	Quality compounds with every merge

• 🚦 Non-blocking by default — purely feedback. No surprise red CI, ever, unless you choose to enforce a score floor
• ⚡ One-click fixes — comment /apply-optimize on any PR and the AI suggestions are committed to the branch automatically

Think of it as a spell-checker for your skills — always on, always improving, costs nothing.

Please check one:

• Yes — open a follow-up PR with the skill review + optimize GitHub Action
• No thanks, I'll manage skill quality manually

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Honest disclosure — I work at @tesslio where we build tooling around skills like these. Not a pitch - just saw room for improvement and wanted to contribute.

Want to self-improve your skills? Just point your agent (Claude Code, Codex, etc.) at this Tessl guide and ask it to optimize your skill. Ping me - @rohan-tessl - if you hit any snags.

Thanks in advance 🙏