1
Only 7 of 40 viral prompt codes reliably shift reasoning
The rest are structural tools marketed as reasoning tools. The ones that work all share one feature — rejection logic, not additive instructions.
Free 40-page Claude guide — download today
Free · April 2026 · Version 1.0
The Claude Code Skills Report 2026
What 40 tested prompt codes, 2,392 skill files, and 60 hours of Opus 4.7 vs 4.6 benchmarks reveal about building with Claude.
31-page PDF · No paywall · No email required · CC BY 4.0 license
Why this exists:I got tired of evaluating prompt codes and model upgrades on vibes. Every new Claude release, the discourse was dominated by confident claims from people who hadn't run tests. This report is what three months of controlled testing produces. Every claim has a sample size or a reproducible protocol — or it's flagged as inference.
5 headline findings
What's inside, in one scroll
The short version of every section. The PDF has the data and methodology behind each claim.
2
/skeptic is the highest-signal prefix in the dataset
Caught wrong premises in 11 of 14 test cases (79%) vs 2 of 14 baseline (14%). A 5.5× improvement — the largest measured delta.
3
Opus 4.7's 6% benchmark lift understates the real upgrade
Multi-file code tasks produce working code 2× as often. Long-context holds 94% recall at 720K tokens (vs 54% at 162K on 4.6). Same price.
4
SAP dominates the Claude Code skills ecosystem
Of 845 catalogued skills, SAP is the largest category at 107 skills — 4× the next category. Claude Code's real user base is enterprise platform consultants, not the SaaS founders the discourse focuses on.
5
Claude's moat is the primitive stack, not the model
Skills + hooks + subagents + agent teams + MCP + Cowork — the integrated stack competitors don't match. Users who master the stack get 5-10× the value of users who only use the chat interface.
Report contents
8 sections + 3 appendices · 15,500 words
01
Methodology
How each finding was tested — protocols, sample sizes, limitations
02
The Real Prompt-Code Distribution
Classification framework + the 7/23/7/3 split across 40 codes
03
The 7 Codes That Actually Shift Reasoning
Before/after, test numbers, when to use, failure modes — for each
04
Claude Opus 4.7 vs 4.6
60-hour benchmark: reasoning, coding, long-context, speed, pricing
05
The Claude Code Skills Layer
2,392 files catalogued, SAP dominance, case studies, how to write good skills
06
Agent Teams and Subagents
When orchestration pays off, when it's a tax, the emerging stack
07
Competitive Map
Where Claude Code sits vs Cursor, Copilot, Windsurf — honest assessment
08
Practical Takeaways
5 concrete actions you can take Monday morning
+
Appendix A — Compressed 40-code reference · Appendix B — CLAUDE.md template · Appendix C — About this research
Want the next version when it drops?
Version 2.0 targeted for July 2026 with expanded tests and 30-day follow-up data. One email when it's live — no spam, no daily newsletter pressure unless you want it.
Related
Cheat Sheet — full test data
All 40 deeply-tested codes with before/after transcripts, combo strategies, and failure modes. $15 until May 1.
Insights Dashboard — free
10 classified codes with test results, live-updated. No paywall, no email gate.
Skills Library — 2,392 files
Every skill referenced in Section 5, filterable by category. Free individual downloads.
Share the report
If you find a claim that contradicts your own testing, email team@clskills.in. It'll be cited in v2.